Pontiac Bonneville 3.8L – Grand AM 3.3L – Trans Sport 3.8L (1992 – 1993) Trouble Code Info

Model Year Engine identification System
Bonneville 3.8L 1992-93 VIN  position 8 = L GM
Grand AM  3.3L 1992-93 VIN  position 8 = N GM
Trans Sport 3.8L 1992-93 VIN  position 8 =  L GM

General information

  • Refer to the front of this manual for general test conditions, terminology, detailed descriptions of wiring faults and a general trouble shooter for electrical and mechanical faults.
  • Malfunction indicator lamp (MIL) will illuminate if certain faults are recorded.
  • ECM operates in backup mode if sensors fail , to enable vehicle to be driven to repair shop.
  • Trouble codes can be displayed by the MIL or by using a Scan Tool connected to the data link connector (DLC ).
Bonne-Grand1Bonne-Grand2

Accessing

  • Access data link connector (DLC ).
  • Jump data link connector (DLC) terminals A and B 1.
  • Switch ignition ON. Do NOT start engine.
  • Count MIL flashes. Note trouble codes. Compare with trouble code table.
  • Firstly trouble code 12 will be displayed 3 times.
  • Trouble codes consist of 2 groups, displayed as follows:
* First group indicates the ‘tens’ of the trouble code [2] [A].
* Second group indicates the ‘units’ of the trouble code [2] [C].
* A short pause separates each group [2] [B].
* A long pause separates each trouble code [2] [D] .
* For example: Trouble code 12 displayed [2]. Start of diagnosis.
  •  Each additional trouble code will now be displayed 3 times, in ascending order.
NOTE: If no additional trouble codes are stored, code 12 will continue to be displayed.
  • Trouble codes can also be displayed by using a Scan Tool connected to the data link connector (DLC) 1.

Erasing

NOTE: Disconnecting battery ground lead may cause driveabi/ity problems until the engine management system relearns basic values.
  • Ensure ignition switched OFF.
  • Disconnect battery ground cable for 30 seconds.
  • Reconnect battery ground cable.
  • Repeat checking procedure to ensure no trouble codes remain in ECM fault memory.
NOTE: Disconnecting battery ground lead may also erase memory from electronic units, such as radio.
• Trouble codes can also be erased by using a Scan Tool connected to the data link connector (DLC) 1.

Trouble code  identification

Flash code Fault location Probable cause
12 Start of diagnosis No engine speed (RPM) signal received
13 Oxygen sensor (02S)/heated oxygen sensor (H02S) Wiring open Circuit, 02S/H02S, ECM
14 Engine coolant temperature (ECT) sensor voltage low Wiring short circuit to ground, ECT sensor, ECM
15 Engine coolant temperature (ECT) sensor voltage high Wiring open circuit, ECT sensor, ECM
16 System voltage high/low Wiring, battery, alternator
17 Ignition control system, spark reference signal circuit malfunction Wiring, ICM, ECM
18 Camshaft position (CMP) sensor -circuit malfunction Wiring, CMP sensor, mechanical fault, ECM
21 Throttle position (TP) sensor -voltage high Wiring open circuit/short circuit to positive, TP sensor, ECM
22 Throttle position (TP) sensor -voltage low Wiring open circuit/short circuit to ground, TP sensor, ECM
23 Intake air temperature (IAT) sensor -voltage high Wiring open circuit, IAT sensor, ECM
24 Vehicle speed sensor (VSS) no signal Wiring, VSS, ECM
25 Intake air temperature (IAT) sensor -voltage low Wiring short circuit to ground, IAT sensor, ECM
26 Engine control module (ECM), quad driver/output driver -circuit malfunction Wiring, ECM controlled components, ECM 0
27 Transmission gear switch, signal -circuit malfunction Wiring open circuit/short circuit to ground, 2nd gear switch, 3rd gear switch, ECM
28 Transmission gear switch, signal -circuit malfunction Wiring open circuit/short circuit to ground, 2nd gear switch, 3rd gear switch, ECM
31 Park/neutral position (PNP) switch -malfunction Wiring, PNP switch, ECM
34 Mass airflow (MAF) sensor -voltage low Wiring, poor connections, MAF sensor, ECM
36 Transmission shift solenoid (SS) -circuit malfunction Wiring, 55, ECM
38 Brake pedal pOSition (BPP) switch, torque converter clutch (TCC) Wiring, incorrectly adjusted, BPP switch, ECM
39 Torque converter clutch (TCC) -slipping Wiring, TCC solenoid, transmission mechanical fault, ECM
41 Camshaft position (CMP) sensor -circuit malfunction Wiring, CMP sensor, mechanical fault, ECM
42 Ignition control, timing signal -circuit malfunction Wiring, poor connections, ICM, ECM
43 Knock sensor (K8) -circuit malfunction Wiring, KS, ECM
44 Oxygen sensor (028)/heated oxygen sensor (H028) -mixture lean Wiring open circuit/short circuit to ground, injector(s) blocked, fuel contamination, fuelpressure low, exhaust system leaking, 025/H025,ECM
45 _Oxygen sensor (028)/heated oxygen sensor (H028) -mixture rich Wiring open circuit, fuel pressure high, injector(s) leaking, 025/H025, EVAP purge valve, throttle position (TP) sensor, EGR system, ECM
48 Misfire detected Ignition system, fuel system, 025, engine mechanical fault
51 Engine control module (ECM), PROM malfunction Poor connections, incorrect programming, ECM
53 Exhaust gas recirculation (EGR) solenoid 1 circuit malfunction Wiring, EGR valve, ECM
54 Exhaust gas recirculation (EGR) solenoid 2 circuit malfunction Wiring, EGR valve, ECM
55 Exhaust gas recirculation (EGR) solenoid 3 circuit malfunction Wiring, EGR valve, ECM
56 Engine control module (ECM), quad driver/output driver -circuit malfunction Wiring, ECM controlled components, ECM 0
61 Cruise control, vent solenoid -circuit malfunction Wiring, solenoid valve
62 Cruise control, vacuum solenoid -circuit malfunction Wiring, solenoid valve
63 Cruise control system -performance low Wiring, poor connections, accelerator cable sticking
65 Cruise control servo position sensor -circuit malfunction Wiring, poor connections, servo position sensor
66 AlC refrigerant pressure sensor -voltage low Incorrect refrigerant charge, wiring, AlC refrigerant pressure sensor, ECM
67 Cruise control master switch -circuit malfunction Wiring, poor connections, cruise control master switch
68 Cruise control system -performance high Wiring, poor connections, accelerator cable sticking
69 AlC refrigerant pressure switch, engine coolant blower motors -circuit malfunction Wiring open circuit, AlC refrigerant pressure switch,ECM
99 Cruise control system -engine management has operated in limited power mode Accelerator cable sticking, brake vacuum release valve, cruise control actuator
[1] Depending on model, year and equipment level, the following components may be connected to this circuit. Use of the vehicle wiring diagram is recommended to confirm which components are fitted.
o A/C compressor clutch relay 0 Exhaust gas recirculation (EGR) solenoid
o A/C condenser blower motor relay 0 Malfunction indicator lamp (MIL)
o Engine coolant blower motor relay 0 Torque converter clutch (TCC) solenoid
o Engine coolant ‘hot’ warning lamp 0 Transmission shift solenoids (88)
o Evaporative emission (EVAP) canister purge 0 Transmission shift warning lamp (MT)
valve