Larger slow and medium-speed industrial and marine engines are in a different league since they often feature 14-36 cylinders with larger displacements, which translates to much higher HP ratings.

If you want to find out more about the HP/cylinder ratings of various piston engines, this post is for you.

We at PowerSportsGuide have compiled all you need to know under one roof!

Does the Number of Cylinders Affect Horsepower?

As a rule of thumb, the more cylinders an engine has for a given displacement, the more HP it can generate.

Why?

The answer is the size and weight of the pistons.

Fewer cylinders mean larger and heavier pistons that have more inertia. Larger pistons also require more durable engine internals so they can tolerate the higher load caused by the high torque.

These heavy components limit engine RPM, which translates to lower HP figures.

Other key factors are the layout and design of the cylinders (small-bore vs. big-bore), and the aspiration of the engine.

As an example, a Harley-Davidson with an 833cc, V-twin engine only generates 45-55 HP while sportbikes with 900-1000cc, big-bore engines put out 180-220 HP.

In short, fewer cylinders for a given displacement offer more torque and burn less fuel.

In contrast, more cylinders can rev higher, which translates to more engine power and higher fuel consumption.

If you want to find out more about the average HP/cylinder figures in each engine class, keep reading!

How Much HP Does an Engine have Per Cylinder?

How Much HP Does a Single-Cylinder Engine Have?

A single-cylinder engine can generate anywhere from 1-75 HP depending on its displacement and purpose of use.

You can find the smallest single-cylinder engines in tools and garden equipment. These tiny power sources displace from 25-100cc and generate 1-10 HP.

Smaller lawn movers also come with 100-400cc single engines rated at 10-25 HP.

You can find the most powerful single engines in go-karts, ATVs, snowmobiles, and motorcycles. The engine power of these powersport vehicles ranges from 3 HP up to 75 HP.

Average HP ratings of single-cylinder engines:

• Motorcycles and mopeds: 3-75 HP
• Kid-size and youth snowmobiles: 4-65 HP
• ATVs: 15-50 HP
• Go-karts: 2-45 HP
• Portable outboard motors: 2.5-6 HP
• Tools: 1-10 HP
• Garden machinery: 5-25 HP

Which single-cylinder engine is the most powerful?

As an example, the most powerful single-cylinder motorcycle engine is nestled in the KTM 690 Enduro R and SMC R.

This power source is a 4-stroke, liquid-cooled, 693cc, single engine rated at 75 HP and 53 lb-ft of torque.

How Much HP Does a 2-Cylinder Engine Have?

You can expect the power of a 2-cylinder engine to be in the ballpark of 10-215 HP.

V2 engines in this breed typically generate significantly less power than their inline-2, and flat-2 brothers.

Average HP ratings of 2-cylinder engines:

• Motorcycles: 20-215 HP
• Trikes: 30-110 HP
• ATVs and UTVs: 40-110 HP
• Snowmobiles: 100-170 HP
• Go-karts: 10-20 HP
• Aircraft: 50-200 HP
• Portable outboard motors: 8-25 HP
• Tools and garden machinery: 10-40 HP

Which 2-cylinder engine is the most powerful?

The most powerful 2-cylinder motorcycle engine was used in the Ducati 1299 Superleggera. This limited-edition Ducati housed a 1285cc, L-twin engine that delivered an impressive 215 HP.

How Much HP Does a 3-Cylinder Engine Have?

The engine power of 3-cylinder or “triple” engines averages between 30 and 600 HP, but most of them are rated at 80-200 HP.

The displacement in this class ranges from 300cc up to 2500cc.

Average HP ratings of 3-cylinder engines:

• Cars: 50-600 HP
• Motorcycles: 50-180 HP
• UTVs: 80-180 HP
• Snowmobiles: 65-200 HP
• Outboard motors: 30 – 60 HP
• Aircraft: 50-300 HP
• Jet skis: 60-300 HP
• Tools and garden machinery: 20-50 HP

Which 3-cylinder engine is the most powerful?

The most powerful 3-cylinder engine is Koenigsegg’s “Tiny Friendly Giant.” Utilizing the innovative “freevalve” technology, this 2.0L, 3-cylinder engine features two turbochargers and generates 600 HP and 442 lb-ft of torque.

How Much HP Does a 4-Cylinder Engine Have?

4-cylinder engines can generate anywhere from 50-1400 HP, but most of them put out 80-300 HP.

The displacements of most production 4-cylinder engines fall into the ballpark of 1000-3500cc.

Average HP ratings of 4-cylinder engines:

• Cars: 70-450 HP
• F1 cars: 600-1400 HP
• Motorcycles: 55-300 HP
• Outboard motors: 50-200 HP
• Inboard boat motors: 30-300 HP
• Jet skis: 100-310 HP
• Aircraft: 50-500 HP

Which 4-cylinder engine is the most powerful?

The most powerful 4-cylinder power sources were the turbo inline-4 engines of F1 cars, which were rated at no less than 600-1350 HP.

How Much HP Does a 5-Cylinder Engine Have?

Unlike their smaller siblings, 5-cylinder engines are used much less frequently, and with good reason.

Although they provide more power than 4-cylinder engines along with a crisp throttle response and great fuel efficiency, they feature a complex architecture and tend to cause more vibration.

Only a few racing motorcycles and cars were designed with 5-cylinder engines, including:

• Land Rover Ninety (2.5 L, five-cylinder turbo diesel, 122 HP)
• 2nd gen. Ford Focus RS (2.5 L, five-cylinder turbo, 301 HP)
• Audi Sport Quattro (2.1 L, five-cylinder turbo, 306 HP)
• Audi TT RS (2.5 L turbocharged inline-5, 360 HP)
• 2022 2020 Donkervoort D8 GTO-JD70 (2.5L five-cylinder turbo, 415 HP)
• 2020 KTM X-Bow GTX (2.5L, five-cylinder turbo from Audi, 592 HP)

Which 5-cylinder engine is the most powerful?

One of the most powerful 5-cylinder car engines is the 2.5L, 5-cylinder turbo engine in the impressive KTM X-Bow GTX.

The engine of this unique vehicle is built by Audi and generates 592 HP.

Therefore, you can expect the power of a 5-cylinder engine to be in the ballpark of 100-600 HP.

How Much HP Does a 6-Cylinder Engine Have?

When it comes to recreational vessels and street vehicles, 6-cylinder engines can generate an impressive 70-800 HP.

These power sources are commonly used in trucks and cars, but they also appear in airplanes and even motorcycles.

The most common 6-cylinder engine arrangement is arguably the V6, but you can also find vehicles with inline-6 or even flat-6 engines with a capacity of 2000-7000cc.

Average HP ratings of 6-cylinder engines:

• Cars: 120-800 HP
• F1 cars: 600-1050 HP
• Pickup trucks: 300-500 HP
• Motorcycles: 70-160 HP
• Outboard motors: 175-300 HP
• Aircraft: 200-400 HP

How Much HP Does a 7-Cylinder Engine Have?

7-cylinder engines are typically radial aero power mills rated at 100-300 HP depending on the make and model.

These units typically feature air-cooling and a displacement of 3000-10000cc.

Aside from airplanes, inline-7 diesel engines are also used in marine applications.

Since they would cause too much noise and vibration, 7-cylinder engines are not used in cars and trucks.

How Much HP Does an 8-Cylinder Engine Have?

You can expect the performance of an 8-cylinder engine to be 200-1000+ HP. These power sources can feature both inline-8, flat-8, or V8 configurations.

The displacements of most of these units average between 4000-10000cc.

Average HP ratings of 8-cylinder engines:

• Cars: 250-1000 HP
• Pickup trucks: 300-1000 HP
• Outboard motors: 225-450 HP

How Much HP Does a 10-Cylinder Engine Have?

The majority of 10-cylinder engines produce 300-700 HP while some high-performance units can exceed an incredible 1000 HP.

These powerhouses typically displace between 4000 and 16000cc and enjoy inline-10, flat-10, or V10 layouts. The latter is commonly used in street vehicles and boats since the V architecture offers a more compact size.

Surprisingly, some high-end cars feature flat-10 engines, but the V10 configuration is far more prevalent in this class.

Average HP ratings of 10-cylinder engines:

• Cars: 300-1000 HP
• Pickup trucks: 300-1000 HP
• Outboard motors: 350-400 HP

How Much HP Does a 12-Cylinder Engine Have?

12-cylinder engines are used for powering luxury and hypercars, heavy vehicles, boats, and airplanes. They most often feature a V12 arrangement and displace anywhere from 4000-24000cc.

V12 engine configurations also appear in the most powerful outboard motors, which are typically rated at 500-600 HP.

Interestingly, some V12 engines are built by gearing together two V6 engines.

Average HP ratings of 10-cylinder engines:

• Cars: 600-1000 HP
• Outboard motors: 500-600 HP
• Aircraft: 1000-1600 HP

How Much HP Does a 14-Cylinder Engine Have?

14-cylinder engines are rarely used in street vehicles and aircraft. Instead, these massive diesel engines are designed for marine propulsion and power generation.

As an example, MAN B&W manufactures V14 engines rated at 9,400-24,400 HP.

In contrast, the Finnland-based Wärtsilä markets V14 diesel engines that can exceed an incredible limit of 100,000 HP.

How Much HP Does a 16-Cylinder Engine Have?

16-cylinder engines are typically a combination of two 8-cylinder engines. The base engines can feature inline-8, flat-8, W8, or more commonly V8 engines.

The first V16 engine was an aircraft engine designed in 1910, while the first V16 cars hit roads in the ‘30s.

As a rule of thumb, these vintage V16 car engines generated 150-600 HP, while the power of V16 aircraft engines averaged between 400 and 1500 HP.

Due to their size and complexity, engines with 18 or more cylinders are rarely used in street vehicles and airplanes.

The largest, 18-36 cylinder power sources are typically designed for industrial use or marine applications, but they were also used by the aircraft industry.

Engine HP per Cylinder Chart

For better comparison, we’ve collected the average HP/cylinder ratings of the most common street vehicles, recreational boats, and aircraft engines into one chart.

Disclaimer: This chart is for informational purposes only!

Conclusion – Does More Cylinders Mean More HP?

Based on our research, the average multi-cylinder vehicle engine can produce about 5-130 HP per cylinder, while singles can deliver a maximum of 75 HP.

Note that this ballpark estimation doesn’t include large marine and industrial engines.

These units are typically slow and medium-speed diesel engines that have significantly higher displacement and engine power than vehicle engines.

They typically feature 16-36 cylinders and can reach or exceed the eye-dropping limit of 100,000 HP.

References:

Thedrive.com, Airandspace.si.edu, Oldmachinepress.com

If you want to find out more about the architecture of piston engines, this post is for you.

We at PowerSportsGuide have compiled all you need to know under one roof!

How Many Cylinders are in an Engine?

Is There a Single-Cylinder Engine?

As the name suggests, a single-cylinder engine is a piston engine featuring just one cylinder. This engine configuration is known for its simplicity and easy maintenance.

The average displacement of single engines start at 25cc and go up to 700cc, but a custom 1000cc single-cylinder motorcycle engine was also built.

What vehicles and machnies have a single-cylinder engine?

• Motorcycles
• Motor scooters
• Kid-size snowmobiles
• ATVs
• Go-karts
• Portable outboard motors
• Portable tools
• Garden machinery (such as chainsaws, lawnmowers, or cultivators)

Is There a 2-Cylinder Engine?

2-cylinder or “twin” engines feature two pistons and two cylinders with a capacity of 200-2000cc.

In terms of cylinder arrangement, twin engines can feature both inline, V, or flat (boxer) architecture.

Which vehicles and machnies have a twin-cylinder engine?

• Motorcycles
• Trikes
• ATVs
• UTVs
• Snowmobiles
• Go-karts
• Vintage 2-stroke jet skis
• Portable outboard motors
• Portable tools
• Garden machinery (such as lawnmowers, or cultivators)

Is There a 3-Cylinder Engine?

3-cylinder or “triple” engines feature three pistons and three cylinders, most often in an inline arrangement.

The displacement in this class ranges from 300cc up to 2500cc.

Which vehicles have a 3-cylinder engine?

• Cars
• Motorcycles
• UTVs
• Go-Karts
• Snowmobiles
• Outboard motors
• Jet skis
• Aircrafts
• Tools
• Garden tractors

Is There a 4-Cylinder Engine?

As one can expect, 4-cylinder engines feature four pistons and four cylinders. These power sources typically utilize an inline configuration, but V4 and flat-four engines do exist.

The displacements of mass-produced 4-cylinder engines average between 350cc and 3200cc.

However, the largest 4-cylinder car engine ever built was a 28353cc (yes, it’s 28.4L) powerhouse planted in the little-known Fiat S76.

Which vehicles have a 4-cylinder engine?

• Cars
• Motorcycles
• UTVs
• Outboard motors
• Inboard boat motors
• Jet skis
• Aircrafts
• Tools
• Garden tractors

Is There a 5-Cylinder Engine?

Compared to their siblings, 5-cylinder engines are much less common. They can feature both a V5 and inline-5 configurations.

These special power sources combine many advantages of 4- and 6-cylinder engines. They provide more power and torque than 4-cylinder engines along with a great throttle response and fuel efficiency.

Which vehicles have a 5-cylinder engine?

Only a few vehicles use a 5-cylinder engine, including some cars and special V5 racing motorcycles.

Is There a 6-Cylinder Engine?

6-cylinder engines are commonly used in cars and trucks, but they are also used for powering some high-performance motorcycles and even airplanes.

You can expect the capacity of these engines to be 2000-7000cc, while their arrangement could be V6, inline-6, or flat-6.

Which vehicles have a 6-cylinder engine?

• Cars
• Trucks
• Motorcycles
• Outboard motors
• Inboard boat motors
• Aircrafts
• Heavy vehicles
• Industrial engines

Is There a 7-Cylinder Engine?

Contrary to popular belief, 7-cylinder engines do exist. These power mills are typically air-cooled radial aero engines with a displacement of 3000-10000cc.

Aside from the radial configuration, 7-inline engines are also used in marine applications. The key advantage of these power mills is their modular design, meaning that they often feature separate heads on each cylinder.

Since they would cause too much noise and vibration, 7-cylinder engines are not used in cars and trucks.

If manufacturers can develop much smoother 6- and 8-cylinder engines, why would they bother with a 7-cylinder unit?

Is There an 8-Cylinder Engine?

8-cylinder engines come with both inline-8 and V8 configurations while their displacement typically varies between 4000 and 10000cc.

Which vehicles have an 8-cylinder engine?

• Cars
• Trucks
• Outboard motors
• Boats
• Aircrafts
• Heavy vehicles
• Industrial engines

Is There a 9-Cylinder Engine?

9-cylinder engines are the larger brothers of 7-cylinder air-cooled radial aircraft engines. The marine industry also uses 9-cylinder diesel engines, which are often turbocharged.

In contrast, 9-cylinder engines are not used in cars, trucks, or other street vehicles.

Is There a 10-Cylinder Engine?

The majority of 10-cylinder engines displace between 4000 and 16000cc and feature inline-10 or V10 architecture. The latter is commonly used in vehicles since the V configuration ensures a more compact size.

Some high-performance cars feature flat-10 engines, but the V10 configuration is far more prevalent.

In contrast, industrial power mills in this class can be either V10 or modular inline-10 engines.

Which vehicles have a 10-cylinder engine?

• Cars
• Trucks
• Outboard motors
• Boats and ships
• Aircrafts
• Heavy vehicles
• Industrial engines

Is There an 11-Cylinder Engine?

Although 11-cylinder engines do exist, they are quite rare. These air-cooled, radial 11-cylinder power mills were used on aircraft in the last century.

One of these rare engines was the Clerget 11Eb (200 HP), built by E. Clerget-Bin and Co. in 1918.

Is There a 12-Cylinder Engine?

12-cylinder engines are typically used in high-end cars, trucks, heavy vehicles, boats, and airplanes. They most often feature a V12 arrangement and displace anywhere from 4000-25000cc.

However, diesel V12 marine engines stand out in the crowd with their sizeable cylinders.

For example, the Wärtsilä 46F is an incredible V12, 1157000cc (1,157 L) power mill rated at 19,300 HP (14,400 kW).

Interestingly, some V12 engines are built by combining two V6 engines.

Which vehicles have a 12-cylinder engine?

• Cars
• Trucks
• Outboard motors
• Ships and marine applications
• Aircrafts
• Heavy vehicles
• Industrial engines

Is There a 14-Cylinder Engine?

V14 engines are quite rare, and are typically large diesel engines used for marine propulsion, heavy vehicles, and power generation.

As an example, the MAN B&W produces V14 engines with the engine power of 9,400-24,400 HP.

Wärtsilä is another well-known manufacturer that offers V14 diesel engines.

Is There a 16-Cylinder Engine?

16-cylinder engines are typically a combination of two 8-cylinder engines. The base engines can be either inline-8 or V8 engines, but the latter is much more prevalent.

The first V16 engine was an aircraft engine designed in 1910.

Which vehicles have a 16-cylinder engine?

• Ships and marine applications
• Aircrafts
• Heavy vehicles (locomotives, etc.)
• Industrial engines

Is there a car with 16 cylinders?

Although cars with 16-cylinder engines are no longer produced, there were some iconic cars with V16 engines in the 1930s.

The very first V16 car was the 1930 Cadillac V-16, featuring a 7.4L, V16, OHV engine.

Is There an 18-Cylinder Engine?

When it comes to 18-cylinder engines, we can distinguish three fundamentally different designs.

One rarely-used configuration was the W18 engine featuring three banks of six cylinders in a W layout.

This configuration was used in some concept cars and aircraft manufactured in the ‘20s and ‘30s.

Another lesser-known layout was the twin-row 18-cylinder radial arrangement. These engines were virtually two rotary 9-cylinder engines built behind each other.

These air-cooled radial engines appeared in aircraft from the late ‘30s.

In contrast, a much more common 18-cylinder engine is the standard V18 power mills, which are typically low-speed diesel engines.

These are commonly used in ships, locomotives, trucks, and electricity generators.

Which vehicles have an 18-cylinder engine?

• Hypercar concepts
• Ships and marine applications
• Aircrafts
• Heavy vehicles (locomotives, trucks, etc.)
• Industrial engines

Is there a car with 18 cylinders?

W18 car engines were used in the concept cars of the Bugatti Veyron in the ‘90s.

In the late ‘60s, Ferrari also designed a 3.0L, W18 engine as a prototype Formula One engine.

Is There a 20-Cylinder Engine?

20-cylinder engines typically have a V architecture where two banks of V10 cylinders are connected to the same crankshaft.

Labeled as V20 engines, these power sources are commonly used in ships, heavy vehicles, and in industrial applications.

Besides vessels and vehicles, aircraft also used to use 20-cylinder engines.

One of the most iconic 20-cylinder aircraft engines was built by Anzani in 1913. This tow-row air-cooled radial aircraft engine featured two merged 10-cylinder radial engines.

Which vehicles have a 20-cylinder engine?

• Aircrafts
• Ships and marine applications
• Heavy vehicles (locomotives, trucks, etc.)
• Industrial engines

Is There a 22-Cylinder Engine?

22-cylinder radial engines were used in aircraft in the early ‘40s. One of the most well-known was the Pratt & Whitney R-4360 engine, featuring two rows of 11 cylinders each.

Engines with 22 cylinders are typically not used in automotive and marine industries.

Is There a 24-Cylinder Engine?

24-cylinder engines are much more common than their 22- and 26-cylinder counterparts.

The most well-known engine configuration in this class is the V24, where two banks of 12 cylinders are mounted around the same crankshaft in a V layout.

However, most V24 engines consist of two V12 engines geared together.

This type of engine is used in marine applications, generators, and in heavy machines.

In contrast, aero V24 engines are typically two 12-cylinder rotary engines geared together.

An exciting exception was the Allison X-4520 24-Cylinder Aircraft Engine that utilized a unique X layout.

Other famous V24 engines were as follows:

• Fiat AS.6 aircraft engine (for the Macchi M.C.72 airplane)
• Detroit Diesel Series 71 24V71 engine
• Duesenberg W-24 Marine Engine
• Allison X-4520 24-Cylinder Aircraft Engine
• Napier H-24 Sabre Aircraft Engine
• Junkers Jumo 223 (2-stroke)

Which vehicles have a 24-cylinder engine?

• Aircrafts
• Ships and marine applications
• Heavy vehicles (locomotives, trucks, etc.)
• Industrial engines

Is There a 28-Cylinder Engine?

The rare 28-cylinder power mills were air-cooled radial aero engines featuring 7 cylinders in four rows or 14 cylinders in two rows. These incredible power mills were rated at 1,000-4,300 HP depending on the make and model.

The most well-known 28-cylinder engines include:

• Alfa Romeo 1101 28-Cylinder Aircraft Engine
• Pratt & Whitney R-4360 Wasp Major
• Mitsubishi Ha-26 Aircraft Engine

Is There a 36-Cylinder Engine?

The largest radial aircraft engine built in the US was the 36-cylinder Lycoming XR-7755.

This unit was designed for the Convair B-36 aircraft, but only two prototypes were built before the project was canceled.

In terms of specifications, the Lycoming XR-7755 was a liquid-cooled, 127 L, 36-cylinder, four-row radial engine.

Conclusion

While most internal combustion engines feature 1-12 cylinders, the largest units house 14-36 cylinders.

The smallest single- and twin-cylinder power mills are used in tools, garden equipment, portable outboards, and motorcycles.

Cars typically utilize inline-3, 4, or 6, as well as V6, V8, or V12 engines.

The largest engines with 14-24 cylinders are typically used in aircraft, electric generators, ships, and heavy vehicles like locomotives and haul trucks.

Some vintage aircraft was also designed with impressive 26-36-cylinder radial engines, which are no longer in production.

References:

Thedrive.com, Airandspace.si.edu, Oldmachinepress.com

If you want to find out more about these codes and read all generic OBD2 codes in one chart, you’ve come to the right place.

For your convenience, we at PowerSportsGuide have compiled them all under one roof!

What are OBD2 Codes?

OBD2 codes are On-Board-Diagnostic Trouble Codes, which are often referred to as fault codes, error codes, or DTC codes. As the name suggests, these codes are intended to describe a malfunction when your vehicle is having issues. Each car and light truck sold in 1996 and beyond comes with an OBD2 port as standard, to which an OBD2 diagnostic tool can be connected.

When the Onboard Diagnostic (OBD) system detects an issue, it activates the check engine light and records a DTC code in the memory of the vehicle’s main computer.

In other words, if your vehicle has a malfunction, the system warns you and helps diagnose the issue by recording a unique code.

These codes can help dealers, mechanics, and manually-inclined owners understand the nature of the problem and a further diagnosis.

Until the mid-’90s, each manufacturer used its own brand-specific diagnostic code system, which caused many headaches for owners and mechanics.

But everything changed in 1996 when a new standardized OBD2 become mandatory for all new cars and light trucks being sold in the United States.

The OBD2 system specifies not only a standardized DTC code list but also the electrical signaling protocols and the design and pinout of the OBD2 diagnostic port.

Although the OBD2 standard was established for cars and light trucks, more and more powersport vehicles are now using generic OBD2 codes.

How do You Read OBD2 Codes?

OBD2 codes can be read with a dedicated OBD2 diagnostic tool, which can be a reader and scanner. The former can be used for reading and deleting OBD2 codes, while scanners can produce more complex diagnostics and troubleshooting tips. The most advanced models come with internal databases, which involve generic OBD2 codes, and sometimes manufacturer-specific fault codes as well.

As a rule of thumb, the two main types of OBD2 diagnostic tools are hand-held units and mobile device-based Bluetooth units.

Let’s take a closer look at each!

1. Hand-Held OBD2 Tools

Hand-held OBD2 readers and scanners have been around for decades. These small devices are typically powered by the vehicle’s battery and have a small screen to display the codes.

They are primarily used for reading the codes, but many of them can clear the codes as well. Beyond these, they provide limited information and features.

This means that you have to record the DTC code and check an official OBD2 code list for further information (found in this post below).

2. Mobile Device-Based OBD2 Tools

In the past, you could exclusively find hand-held OBD2 tools in the marketplace, but today their mobile device-based brothers have become more prevalent.

These modern devices are much smaller and lack any screen. This is no surprise since they can connect to mobile devices like smartphones, tablets, and laptops via a Bluetooth connection.

Thanks to their innovative design, they are controlled by software or an app. Therefore, they have a more advanced interface and produce more detailed information.

How do You Use OBD2 Code Readers and Scanners?

In a nutshell, you can use an OBD2 code reader or scanner in five simple steps:

1. Locate your vehicle’s OBD2 port
2. Plug the OBD2 reader/scanner into the port
3. Turn on the ignition key of the vehicle
4. Pair the OBD2 reader/scanner with the app (in case of a mobile device-based tool)
5. Run the scan
6. Read the OBD2 codes on the screen or the mobile app

Note that many simpler OBD2 devices are powered by the vehicle’s battery, so you have to turn the ignition key to the ON position to bring them to life. However, running the engine is typically not required except when doing real-time diagnostics.

Other models are externally powered but they also require turning the car key to the ON position, since the OBD2 device has to communicate with the car’s main computer.

The OBD2 port in most cars is mounted under the dashboard, typically on the driver’s side, less often on the passenger’s side, or around the center console.

In contrast, a motorcycle’s diagnostic ports are usually hidden under the seat. Since these ports are usually not standard OBD2 connectors, you need a special adapter to convert them into a standard OBD2 port.

How do You Decode OBD2 Codes?

When it comes to decoding OBD2 codes, the general rule is as follows:

• 1^st character: This letter denotes which part of the vehicle is at fault
• 2^nd character: This number tells if it’s a generic OBD code or a manufacturer-specific code
• 3^rd character: This number denotes which of the vehicle’s systems has a malfunction
• 4^th and 5^th characters: These numbers or letters identify the exact error

The be more specific, the different characters of OBD2 codes are as follows:

The first character

The first character is a letter that identifies which part of the vehicle has a malfunction:

• B = Body Code (Includes A/C and Air Bags)
• C = Chassis Code (Include ABS)
• P = Powertrain Code (Engine and Transmission)
• U = Network Code (Wiring Bus)

The second character

The second character tells if it’s a generic OBD code or a manufacturer-specific code. It can be either a ‘0’ or a ‘1’.

• 0 = Generic OBD2 code
• 1 = Manufacturer specific code

The third character

The third character denotes which of the vehicle’s systems has a malfunction. There are seven categories, which are as follows:

• 1 = Fuel and Air Metering
• 2 = Fuel and Air Metering (injector circuit)
• 3 = Ignition systems or misfires
• 4 = Auxiliary emission controls
• 5 = Vehicle speed control and idle control systems
• 6 = Computer output circuit
• 7,8,9 = Transmission (gearbox)

The fourth and fifth characters

The last two characters are used to define the exact fault code, this part is often referred to as “fault description” on the “special fault index” as well. They can be both numbers and letters.

OBD2 Code Interpretation

For example, the interpretation of the P0704 fault code is as follows:

• P = Powertrain fault
• 0 = Generic OBD2 code
• 7 = Transmission
• 04 = Clutch Switch Input Circuit

FAQs About OBD Codes

What Are OBD2 Codes?

OBD2 codes (On-Board Diagnostic Trouble Codes) are used by vehicles’ diagnostic systems to denote malfunctions. The OBD2 standard specifies a special port and a complete list of diagnostic trouble codes. The main idea behind this standard is to make it easier to detect and understand the nature of malfunctions.

What’s the Difference Between OBD and OBD2?

OBD1 was the first-generation OBD standard in California from 1991 through 1996. Each car sold in this state at that time had to be OBD1 compatible. In 1996, the second-generation OBD2 standard was released as the new national standard in the United States.

Which OBD2 Scanner Can Reset Codes?

Yes, most OBD2 scanners and many readers can clear fault codes. However, it always depends on the model, so double-check the specs of the tool before you purchase it.

What Can You do with an OBD2 Device?

OBD2 devices can be used for many purposes, but the most important ones are as follows:

• Read and delete fault codes
• Logging data from the vehicle (fuel consumption, driving logs)
• Running real-time car diagnostics
• Predictive maintenance
• It can be used as a “black box” for vehicles

What is the Difference Between an OBD2 Code Reader and a Scanner?

As the name suggests, OBD2 code readers are simpler devices designed to read and (usually) clear fault codes. In contrast, code scanners come with many more features including diagnostic functions, and built-in fault code databases as well. Hence, they are typically more expensive.

Does a Car Have to be Running to Use OBD2 Scanner?

OBD2 scanners and readers require you to turn ON the ignition key but you don’t have to run the engine to read fault codes.

Do All Cars Have an OBD2 Port?

As a rule of thumb, each car and light truck sold in the US in 1996 and beyond have an OBD2 port.

How Many OBD2 Ports Does a Car Have?

Cars typically have one OBD2 port installed.

How Do You Find the OBD2 Port on Your Car?

The OBD2 port in a car is usually placed on the driver’s side under the dashboard. However, some cars have it on the passenger side, and rarely near the center console.

Generic OBD2 Fault Code Lists

For your convenience, we’ve compiled the official DBD2 fault codes into these lists:

OBD2 P-Code List