Pontiac Firebird 5.7L (1993 – 1995) Trouble Code Info

Model Year Engine identification System
Firebird  5.7L 1993-95 VIN  position 8 = P 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).
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Accessing

  • Access data link connector (DLC).
  • Jump data link connector (DLC) terminals A and B [1].
  • Switch ignition ON. 00 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:
o First group indicates the ‘tens’ of the trouble code [2] [A].
o Second group indicates the ‘units’ of the trouble code [2] [C].
o A short pause separates each group [2] [B].
o A long pause separates each trouble code [2] [D].
o 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).

Trouble code  identification

Flash code Fault location Probable cause
11 Malfunction indicator lamp (MIL) -circuit malfunction Wiring open circuit/short circuit to ground, MIL, ECM
12 Start of diagnosis No engine speed (RPM) signal received
13 Oxygen sensor (02S)/heated oxygen sensor (H02S), bank 1 Wiring open circuit, 02S/H02S, ECM
14 Engine coolant temperature (ECT) sensor voltage high!low Wiring, ECT sensor, ECM
15 Engine coolant temperature (ECT) sensor voltage high Wiring open circuit, ECT sensor, ECM
16 Distributor ignition system, low resolution signal -circuit malfunction Wiring, distributor, ECM
18 Injector(s) -circuit malfunction Wiring, injector(s)
21 Throttle position (TP) sensor -voltage high/ low Wiring, 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/low Wiring, 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 III
27 Engine control module (ECM), quad driver! output driver -circuit malfunction Wiring, ECM controlled components, ECM III
28 1 Engine control module (EGM). quad driver/ output driver -circuit malfunction Wiring, ECM controlled components. ECM 1:1
28 2 Transmission gear pressure switch. signal circuit malfunction Wiring open circuit/short circuit to ground,reverse/D1/D2/D3/D4 gear pressure switch(es),ECM
29 Secondary air injection (AIR) pump relay circuit malfunction Wiring, AIR pump relay, ECM
32 Exhaust gas recirculation (EGR) solenoid Wiring, poor connections, EGR valve, ECM
33 Manifold absolute pressure (MAP) sensor voltage highllow Wiring, hose blockedlleaking, MAP sensor, ECM
34 Manifold absolute pressure (MAP) sensor voltage low Wiring open circuit/short circuit to ground, MAP sensor, ECM
36 Distributor ignition system. high resolution signal-circuit malfunction Wiring, distributor, ECM
37 Brake pedal position (BPP) switch for torque converter clutch (TCC) -high voltage Wiring short to positive, incorrectly adjusted, BPP switch, ECM
38 Brake pedal position (BPP) switch. torque converter clutch (TCC) -low voltage Wiring open circuit, incorrectly adjusted, BPP switch, ECM
41 Ignition control. reference signal -circuit malfunction Wiring open circuit. poor connections, ICM. ECM
42 Ignition control. reference signal -circuit malfunction Wiring short to ground. ICM, ECM
43 Knock sensor (KS) -circuit malfunction Wiring, KS, ECM
44 Oxygen sensor (02S)/heated oxygen sensor (H02S). bank 1 mixture lean Wiring open circuit/short circuit to ground, injector(s) blocked. fuel contamination. fuel pressure low. exhaust system leaking, 02S/H02S,ECM
45 Oxygen sensor (02S)lheated oxygen sensor(H02S). bank 1 -mixture rich Wiring open circuit, fuel pressure high, injector(s) leaking, 02S/H02S, EVAP purge valve, throttle position (TP) sensor, EGR system, ECM
46 Immobilizer system. code -malfunction Incorrect key, ECM
47 Knock control module. removable part in ECM -circuit malfunction Wiring. poor connection, missing knock control module. ECM
48 Mass airflow (MAF) sensor -no signal Wiring. poor connections, MAF sensor, ECM
50 System voltage low Alternator
51 Engine control module (ECM). PROM -malfunction Poor connections, incorrect programming, ECM
53 System voltage high Alternator
55 Engine control module (ECM). fuel lean monitor Fuel filterllines blocked, fuel contamination
58 Transmission fluid temperature (TFT) sensorvoltage low Wiring short circuit to ground, TFT sensor, ECM
59 Transmission fluid temperature (TFT) sensorvoltage high Wiring open circuit, TFT sensor, ECM
61 AlC system -performance Refrigerant low, wiring, AlC refrigerant pressure sensor, AlC evaporator temperature sensor, ECM
63 Oxygen sensor (02S)/heated oxygen sensor(H02S), bank 2 Wiring open circuit, 025/H025, ECM
64 Oxygen sensor (02S)/heated oxygen sensor (H02S), bank 2 -mixture lean Wiring open circuit/short circuit to ground, injector(s) blocked, fuel contamination, fuel pressure low, exhaust system leaking, 025/H025,ECM
65 Oxygen sensor (02S)/heated oxygen sensor (H02S), bank 2 -mixture rich Wiring open circuit, fuel pressure high, injector(s)leaking, 025/H025, EVAP purge valve, throttle position (TP) sensor, EGR system, ECM
66 AlC refrigerant pressure sensor -voltage low Wiring open circuit/short circuit to ground, AlC refrigerant pressure sensor, ECM
67 AlC refrigerant pressure sensor -circuit malfunction Wiring open circuit, AlC refrigerant pressure sensor, ECM
68 AlC compressor clutch relay -circuit malfunction Wiring short circuit, AlC compressor clutch relay, ECM
69 AlC compressor clutch relay -circuit malfunction Wiring open circuit, AlC compressor clutch relay, ECM
70 AlC compressor clutch relay, control signal -circuit malfunction Wiring, AlC compressor clutch relay, ECM
71 AlC evaporator temperature sensor -voltage high Wiring, poor connections, AlC evaporator temperature sensor
72 Vehicle speed sensor (VSS) -loss of signal Wiring, V55, ECM
73 Transmission fluid pressure (TFP) controlsolenoid -circuit malfunction Wiring, poor connection, TFP solenoid
74 Traction control system (TCS), active signal -malfunction Wiring short to ground, AB5ITC5, ECM
75 System voltage low, engine control module (ECM) Wiring, battery, alternator, ECM
77 Engine coolant blower motor relay -circuit malfunction Wiring, engine coolant blower motor relay, ECM
79 Transmission fluid temperature (TFT) high Transmission mechanical fault, towing weightlimit exceeded
80 Torque converter clutch (TCC) -slipping Wiring, TCC solenoid, transmission mechanical fault, ECM
81 Transmission shift solenoid (SS), 2nd-3rd -circuit malfunction Wiring, 55, ECM
82 Transmission shift solenoid (SS), 1st-2nd circuit malfunction Wiring, 55, ECM
83 Reverse gear inhibit solenoid -circuit malfunction Wiring, reverse gear inhibit solenoid, ECM
84 Transmission 3rd-2nd control solenoid -circuit malfunction Wiringcontrol solenoidECM
84 Skip shift solenoid -circuit malfunction Wiringskip shift solenoidECM
85 Torque converter clutch (TCC) solenoid -stuckON Wiring open circuit/short circuit to ground,transmission internal wiring, TCC solenoid, transmission mechanical faultECM
90 Torque converter clutch (TCC) solenoid circuit malfunction Wiring, TCC solenoidECM
91 Skip shift warning lamp -circuit malfunction Wiring, skip shift warning lampECM
97 Engine control module (ECM), vehicle speed sensor (VSS) output signal -circuit malfunction Wiringpoor connections, ECM
99 Engine control module (ECM), tachometer output signal -circuit malfunction Wiring, poor connections, ECM