Got this from a class I was in recently, thought it was interesting.
How to basically read OBDll Standardized Diagnostic Trouble codes.
The codes start with a letter:
The trouble code area: P- Powertrain B- Body C- Chassis U- Network Fault
Who created this code:
0- SAE defined code 1- Manufacture defined code 2- Manufacture (they ran out of codes for 1 so they expanded to "2")System:
0- Total system 1- Air-fuel control 2- Air-fuel control 3- Ignition system or misfire 4- Auxiliary Emission Controls 5- Idle or speed controls 6- Computer system (PCM or I/O) 7- Transmission 8- Non-computer controlled PowertrainThe last two digits indicate the specific problem area
So the code P1711 would tell us:
P- Powertrain
1- It's a manufacture's code 7- Transmission 11- Transmission oil temperature circuit out of rangeand the code P0300 would tell us:
P- Powertrain O- It's a SAE mandated code
3- Ignition system or misfire 00- random misfire detected