OBD-II codes consist of a number of parts. Here is a sample OBD2 code:

P0171

Here is a breakdown of what each digit of the code means:
First Character - System

The first character identifies identifies the system related to the trouble code.

* P = Powertrain
* B = Body
* C = Chassis
* U = Undefined

Second Digit - Code Type

The second digit identifies whether the code is a generic code (same on all OBD-II equpped vehicles), or a manufacturer specific code.

* 0 = Generic (this is the digit zero -- not the letter "O")
* 1 = Enhanced (manufacturer specific)

Third Digit - Sub-System

The third digit denotes the type of sub-system that pertains to the code

* 1 = Emission Management (Fuel or Air)
* 2 = Injector Circuit (Fuel or Air)
* 3 = Ignition or Misfire
* 4 = Emission Control
* 5 = Vehicle Speed & Idle Control
* 6 = Computer & Output Circuit
* 7 = Transmission
* 8 = Transmission
* 9 = SAE Reserved
* 0 = SAE Reserved

Fourth and Fifth Digits

These digits, along with the others, are variable, and relate to a particular problem. For example,a P0171 code means P0171 - System Too Lean (Bank 1). To lookup your particular code, visit our OBD Trouble Codes section.

 

thanks uncle bubba that will help me when i see a thread with a code in it i might be able to help someone with that there new fangled electronic engine by crappy just might

 

Nice post there Uncle bubba that is some very useful info.

 

half damn century old and still learnin here......thanks man

 

me too whit but too old to remember