About Trouble Codes

About SAE Defined Codes
1st character:
- Pxxxx Powertrain System Codes
- Bxxxx Body System Codes
- Cxxxx Chassis System Codes
- Uxxxx Future Systems

2nd character:
- P0xxx SAE Defined Powertrain Codes
- P1xxx Manufacturer Defined Powertrain Codes

3rd character:
- Px1xx Air and Fuel Codes
- Px2xx Air and Fuel Codes
- Px3xx Ignition System Codes
- Px4xx Emission Control Codes
- Px5xx Speed and Idle Codes
- Px6xx Computer and Output Signal Codes
- Px7xx Transmission Codes
- Px8xx Transmission Codes
- Px9xx Control Module Input And Output Signals

4th and 5th characters are used to specify components and systems.