PCM OBD1 Engine Control Trouble Codes
From SaturnWiki
Use a paper clip to jumper Terminal A and B of the ALDL *Assembly Line Diagnostic Link* which is above your left knee. Terminal A is an internal ground and is the top right terminal in the connector. Terminal B is directly adjacent and to the left of Terminal A.
Turn the ignition to ON.
All codes are 2 digits between 11 and 99. Codes are displayed on the SES light by flashing the light with short and long pauses to distinguish digits of one code from digits of another. The short pause is used between digits of the same code, long pauses are between codes. Also, each code is flashed three times before going to the next code.
For example, the sequence of code 12 will be: flash, pause, flash-flash, long pause, then repeat 2 times. If Code 12 is not displayed, the self-diagnostic pogram i snot functioning properly.
If only Code 12 is displayed, no system malfunctions have been stored.
Any existing system fault codes are displayed in order from low to high, except for Code 11.
Diagnostic Trouble Codes and Engine Information Codes for OBD1 Engine Control Modules
Diagnostic Trouble Codes
- 11 Transmission Diagnostic Codes Present
- 12 Diagnostic Check Only (Flash Code)
- 13 Oxygen Sensor Circuit - Open/Not Ready
- 14 Engine Coolant Temperature Circuit - Temperature Out of Range High
- 15 ECT Circuit - Temperature Out of Range Low
- 17 PCM Fault - Pull-Up Resistor
- 19 (1991 Perf (LLO), 1992-1994 Vehicles) 6X Signal Fault
- 21 TP Sensor Circuit - Voltage Out of Range High
- 22 TP sensor Circuit - Voltage Out of Range Low
- 23 IAT Circuit - Temperature Out of Range Low
- 24 VSS Circuit - No Signal
- 25 IAT Circuit - Temperature Out of Range High
- 26 Quad Driver Output Fault
- 32 EGR System Fault
- 32 (NB6 Emission Vehicles) Linear Exhaust Gas Recirculation (EGR) System
- 33 Map Circuit - Voltage Out of Range High
- 34 Map Circuit - Voltage Out of Range Low
- 35 Idle Air Control (IAC) - RPM Out of Range
- 41 Ignition Control (IC) Circuit - Open or Shorted
- 42 Bypass Circuit - Open or Shorted
- 43 Knock Sensor Circuit (KS) - Open or Shorted
- 44 Lean Oxygen Sensor Signal
- 45 Rich Oxygen Sensor Signal
- 46 (1991 Base (LKO) Vehicles) Power Steering Pressure Circuit - Open
- 49 RPM - High Idle (Vacuum Leak)
- 51 PCM Memory Error
- 55 A/D Error
- 81 (1993-1994 Vehicles) ABS Message Fault
- 82 PCM - Internal Communication Fault
Engine Information Flags
- 16 Electronic Variable Orifice (EVO) Fault
- 27 (1993-1994 Vehicles) Quick Quad Driver Output Fault
- 48 Reference Input - Intermittent or Noisy
- 52 Battery Voltage Out of Range
- 53 Knock Sensor Circuit - Knock Present
- 54 Five Volt Reference Grounded
- 58 Battery Voltage Unstable
- 61 (1991 Base (LKO) Vehicles) 6X Signal Fault
- 63 Option Check Sum Error
- 67 (1991-1992 Vehicles) Handwheel Sensor Circuit Fault
- 71 Engine Cooling System - Temperature High
- 72 Engine Cooling System - Temperature Low
- 73 ECT Unstable
- 74 ECT/Trans Temp Sensor Ratio Error
- 75 IAT Unstable
- 76 TP Sensor Voltage vs Map Voltage - Out of Range
- 83 (1993-1994 Vehicles) Low Coolant Flag
- 84 (1993-1994 Vehicles) PCM - Internal Communication Failure
