A diagnostic test machine is a vehicle diagnostic device that establishes a connection between your car and diagnostic software to detect issues with different components of the car from your vehicle’s systems. Each issue is assigned a different code.
In this guide, we take a look at necessary car diagnostic codes and explain these car fault codes.
Car Diagnostic Codes List
Car diagnostic codes start with the letter ‘P’ followed by a four-digit numeric code. To scan the issues, an OBD reader is plugged into the port under the driver’s dashboard and used as a car diagnostic codes scanner. Following is a list of car diagnostic codes on a diagnostic test machine.
P0100 – P0199 — Fuel and Air Metering
These codes are used to monitor a vehicle’s fuel and air-fuel ratio to identify if an oxygen sensor is failing, as well as its emissions and fuel efficiency.
Codes within this range are indicative of the following issues:
- P0135: O2 Sensor Heater Circuit Malfunction (Bank 1, Sensor 1)
- P0141: O2 Sensor Heater Circuit Malfunction (Bank 1, Sensor 2)
- P0171: System Too Lean (Bank 1)
- P0174: System Too Lean (Bank 2)
P0200-P0299 — Fuel and Air Injector Circuit
The codes within this range are related to bad fuel injectors.
Codes within this range are indicative of the following issues:
- P0200: Injector Circuit Malfunction
- P0218: Transmission Over Temperature Condition
P0300-P0399 — Ignition System
Codes from P0300 to P0399 indicate problems with the car’s ignition system. The ignition system is used to receive high voltage from the car’s battery and then transmit it to the spark plug to ignite the fuel-air combination.
Codes within this range are indicative of the following issues:
- P0300: Random/Multiple Cylinder Misfire Detected
- P0301: Cylinder 1 Misfire Detected — Cylinder number 1 has an insufficient amount of fuel and is thus experiencing misfires.
- P0302: Cylinder 2 Misfire Detected — Cylinder number 2 has an insufficient amount of fuel and is thus experiencing misfires.
- P0303: Cylinder 3 Misfire Detected — Cylinder number 3 has an insufficient amount of fuel and is thus experiencing misfires.
- P0304: Cylinder 4 Misfire Detected — Cylinder number 4 has inan sufficient amount of fuel and is thus experiencing misfires.
- P0325: Knock Sensor 1 Circuit Malfunction (Bank 1 or Single Sensor)
P0400-P0499 — Auxiliary Emissions Controls
These codes will identify problems with the evaporative emission control (EVAP) systems in the system. The purpose of the EVAP is to block gas fumes from reaching the environment, reducing air pollution.
Codes within this range are concerned with the following faults:
- P0401: Exhaust Gas Recirculation Flow Insufficient Detected
- P0411: Secondary Air Injection System Incorrect Flow Detected
- P0420: Catalyst System Efficiency Below Threshold (Bank 1)
- P0430: Catalyst System Efficiency Below Threshold (Bank 2)
- P0440: Evaporative Emission Control System Malfunction
P0500-P0599 — Vehicle Speed Controls and Idle Control System
These codes will keep track of the vehicle’s speed and idle. These codes are indicative of problems with the vehicle speed sensor.
Codes within this range are indicative of the following issues:
- P0500: Vehicle Speed Sensor Malfunction
This code represents inaccurate speed measurement or lack of signals from the vehicle’s speed sensor.
- P0505: Idle Control System Malfunction
When this code appears, it means that the vehicle has difficulty starting, stopping and idling.
P0600-P0699 — Computer Output Circuit
The error codes in this range are related to a faulty computer system. Electronic control units or ECUs, are computers in cars that monitor the performance and drivability of your engine.
Codes within this range are related to the following issues::
- P0600: Serial Communication Link Malfunction
This code refers to a problem with the powertrain control module’s communication link and its supporting control units.
P0602: Control Module Programming Error
This indicates that one of the control modules has a programming fault, which can cause engine issues such as rough idling, stalling, and poor acceleration.
P0604: Internal Control Module RAM Error
This error code indicates a fault in the memory of your vehicle’s internal system.
P0700-P0899 — Transmission
These error codes are related to the system’s transmissions.
Codes within this range are indicative of the following issues:
- P0700: Transmission Control System Malfunction
- P0702: Electrical Transmission Control System
These are all the important car diagnostic codes on a diagnostic test machine. Browse through this wide collection of used cars for sale in the UAE to find vehicles without these faults. To keep up with all what’s happening in the world of the automotive industry, stay tuned to UAE’s leading auto blog.
Related Posts
