GM OBD/OBD2 Codes >> GM 95 5.7L VIN P

GM

95 5.7L VIN P
Flash codeFault locationProbable cause
11Malfunction indicator lamp circuit voltage was wrong for 26 seconds.Wiring open circuit/short circuit to ground, MIL, supply wire, ECM
12Start of diagnosisNo engine speed (RPM) signal received
13Oxygen sensor voltage stays between 0.35 and 0.55 volts for 60 seconds. Engine was at normal operating temperature and had been running for at least 2 minutes after start with a throttle angle above 5%.Wiring open circuit, O2S/H2OS, ECM
14Coolant temperature sensor signal indicates a temperature of over 284° F.Wiring short circuit to ground, ECT sensor, ECM
15Coolant temperature sensor signal indicates a temperature colder than -40° F.Wiring open circuit, ECT sensor, ECM
16A low resolution pulse was not detected by ECM within 720 high resolution timing pulses.Wiring open circuit/short circuit to ground/short circuit to positive, distributor, ECM
17Spark reference circuitWiring open circuit/short circuit to ground, ICM, ECM
18Injector driver circuit voltage to PCM was wrong for 4 seconds.Wiring open circuit/short circuit to ground, supply wire, injectors, ECM
197X reference – circuit malfunctionWiring, mechanical fault, CKP sensor, PROM, ECM
21TPS voltage was above 2.5 volts for 3 seconds when the engine was running, or when the TPS was above 4.8 volts at any time.Wiring open circuit/short circuit to positive, TP sensor, ECM
22TPS voltage was under 0.23 volts when the engine was running.Wiring open circuit/short circuit to ground, TP sensor, ECM
23Inlet air temperature sensor signal showed an air temperature below -31° F for 60 seconds after the engine has been running for 4 minutes.Wiring open circuit, IAT sensor, ECM
24Vehicle speed was 0 MPH when engine speed was between 900 and 3000 RPM and throttle position angle was less than 2% for 5 seconds.Wiring open circuit/short circuit, PROM, VSS, ECM
25Inlet air temperature sensor signal showed an air temperature over 302° F for 12 seconds after the engine has been running for 4 minutes.Wiring short circuit to ground, IAT sensor, ECM
26ECM detected the wrong potential voltage at the #1 quad-driver module circuit for 20 seconds.
27ECM detected the wrong potential voltage at the #2 quad-driver module circuit for 3 seconds.
28ECM detected the wrong potential voltage at the #3 quad-driver module circuit for 3 seconds.
29Secondary air injection pump circuit voltage was wrong for 26 seconds.Wiring open circuit/short circuit to ground/short circuit to positive, AIR valve relay, ECM
31Park/neutral position (PNP) switchWiring open circuit/short circuit to ground, incorrectly adjusted, PNP switch, ECM
32EGR open command did not change the fuel mixture when the command was given during off idle operation. EGR opening should cause the mixture to be slightly richer because of the low oxygen content of the exhaust gas.Wiring open circuit/short circuit to ground, exhaust system blocked, EGR valve, ECM
33MAP sensor signal voltage was too high (low vacuum) for 1 second when throttle opening was under 20% and engine speed was above 1250 RPM.Wiring open circuit/short circuit to positive, hose blocked/leaking, MAP sensor, ECM
34MAP sensor signal voltage was too low (high vacuum) when engine speed was under 700 RPM, or when TPS was greater than 20% with an engine speed above 700 RPM.Wiring open circuit/short circuit to ground, MAP sensor, ECM
35Idle air control (IAC) valveWiring open/short circuit to ground/short circuit to positive, intake system leaking, mechanical fault, IAC valve, ECM
36ECM detected less than 40 high resolution timing pulses between each low resolution pulse for 5 consecutive cycles.Wiring open/short circuit to ground/short circuit to positive, distributor, ECM
37Brake switch stuck ONWiring open/short circuit to ground/short circuit to positive, brake switch, ECM
38Brake switch stuck OFFWiring open/short circuit to ground/short circuit to positive, brake switch, ECM
39Torque converter clutch (TCC) – circuit malfunctionWiring open circuit, BPP switch, TCC solenoid, TCC switch, 3rd gear switch, ECM, mechanical fault
41EST circuit voltage was above 4.6 volts when engine speed was under 1500 RPM.
42PCM did not detect any EST signal within 84 crankshaft revolutions.Wiring open circuit/short circuit to ground, ICM, ECM
43One or both of the knock sensors were either open or grounded for 5 seconds.Wiring open circuit/short circuit to ground/short circuit to positive, KS, PROM, ECM
44Left oxygen sensor voltage was under 0.2 volts for 50 seconds of closed loop operation.Wiring short circuit to ground, injector(s) blocked, fuel contamination, fuel pressure low, exhaust system leaking, HO2S, ECM
45Left oxygen sensor voltage was over 0.7 volts for 50 seconds when the throttle angle was above 4% during closed loop operation.Wiring open circuit, injector(s) leaking, fuel pressure high, HO2S contamination, EVAP canister purge valve, TP sensor, EGR system, HO2S, MAF sensor, ECM
46Immobilizer control module – fuel enable signalIncorrect ignition key, wiring open circuit/short circuit to ground, immobilizer control module, ECM
47Knock sensor signal was not present.Insecure PROM, ECM
48There was no MAF signal when engine was on.Wiring open circuit/short circuit to ground/short circuit to positive, MAF sensor, ECM
50PCM detected an ignition voltage of less than 8.0 volts.Wiring open circuit/short circuit to ground, alternator, ECM
51PROM error.Insecure PROM, incorrect PROM, ECM
52Engine oil temperature was below -31° F after engine had been running for 30 minutes.
53ECM detected a battery voltage above 17.1 volts.Alternator, ECM
54Fuel pump circuit – voltage lowWiring open circuit/short circuit to ground, fuel pump relay, fuel pump, engine oil pressure warning lamp switch, ECM
55ECM detected a lean oxygen sensor voltage for 8 seconds during the power enrichment modes of operation.Fuel filter/lines blocked, fuel contamination
58Transmission fluid temperature (TFT) sensor – high temperature indicatedWiring short circuit to ground, TFT sensor, ECM
59Transmission fluid temperature (TFT) sensor – low temperature indicatedWiring opem circuit, TFT sensor, ECM
61Cruise control vent solenoidWiring open circuit/short circuit to ground/short circuit to positive, cruise control servo, ECM
62Engine oil temperature sensor indicated an oil temperature above 284° F after engine had been running for 30 minutes.
63Right oxygen sensor was open showing a steady voltage between 0.35 and 0.55 volts for 60 seconds after the engine had been running for at least 2 minutes with a throttle angle above 5%.Wiring open circuit/short circuit to ground/short circuit to positive, HO2S contamination, HO2S, ECM
64Right oxygen sensor voltage was below 0.2 volts for 50 seconds of closed loop operation.Wiring short circuit to ground, injector(s) blocked, fuel contamination, fuel pressure low, exhaust system leaking, ECM
65Right oxygen sensor voltage was above 0.7 volts for 50 seconds of closed loop operation when the throttle angle was above 4%.Fuel pressure high, injector(s) leaking, EVAP canister purge valve, TP sensor, EGR system, HO2S contamination, MAF sensor, ECM
66A/C pressure sensor circuit was either open or shorted showing a voltage below 0.12 volts or above 4.86 volts for 10 seconds.Wiring open circuit/short circuit to ground/short circuit to positive, A/C refrigerant pressure sensor, ECM
67ECM did not detect an A/C system pressure change of more than 9 psi when A/C clutch was engaged.Wiring open circuit/short circuit to ground/short circuit to positive, A/C refrigerant pressure sensor, A/C compressor clutch
68ECM detects voltage on the A/C status line for more than 20 seconds after ECM has disengaged the A/C relay.Wiring short circuit to ground/short circuit to positive, A/C compressor clutch relay, ECM
69ECM did not detect any voltage on A/C status line for 20 seconds after ECM had commanded A/C ON.Wiring open circuit, A/C compressor clutch relay, ECM
70A/C clutch relay circuit showed incorrect potential voltage at PCM for 26 seconds.Wiring open circuit/short circuit to ground/short to positive, A/C compressor clutch relay, ECM
72Transmission output speed changed more than 1000 RPM for 2 seconds when vehicle was in gear, or transmission output speed changed more than 2048 RPM when vehicle was in park or neutral.Wiring open circuit/short circuit to ground, VSS, ECM
73Pressure control solenoid return amperage was more than 0.16 amp different than the commanded amperage for 1 second.Wiring open circuit/short circuit to ground/short circuit to positive, ECM
74Traction control system active signal input was 0 volts for more than 2 seconds when vehicle was in park or neutral.
75Ignition voltage was less than set value for 4 seconds when engine speed was above 1000 RPM.Supply wire, alternator, ECM
76Exhaust gas recirculation (EGR) valve solenoid 2Wiring open circuit/short circuit to ground, supply wire, EGR valve, ECM
77Cooling fan relay #1 control potential voltage at PCM was incorrect for 26 seconds.Wiring open circuit/short circuit to ground/short circuit to positive, engine coolant blower motor relay, ECM
78Cooling fan relay #2 and #3 control potential voltage at PCM was incorrect for 26 seconds.Wiring open circuit/short circuit to ground/short circuit to positive, engine coolant blower motor relay, ECM
79Transmission fluid temperature signal indicated a temperature higher than 295° F for 30 minutes, or higher than 306° F at any time.Wiring open circuit/short circuit to ground, TFT sensor, ECM
80Transmission component – slippingWiring open circuit/short circuit to ground/short circuit to positive, TR pressure switch, transmission mechanical fault, ECM
81Transmission 2-3 shift solenoid voltage stayed high for 2 seconds after commanded ON by PCM, or the voltage stayed at zero for 2 seconds after commanded OFF by PCM.Wiring open circuit/short circuit to ground, shift solenoid, ECM
82Transmission 1-2 shift solenoid voltage stayed high for 2 seconds after commanded ON by PCM, or the voltage stayed at zero for 2 seconds after commanded OFF by PCM.Wiring open circuit/short circuit to ground, shift solenoid, ECM
83TCC PWM solenoid voltage stayed high for 2 seconds after commanded ON by PCM, or the voltage stayed at zero for 2 seconds after commanded OFF by PCM.Wiring open circuit/short circuit to ground/short circuit to positive, TCC solenoid, ECM
84Transmission 3-2 shift solenoid voltage stayed high for 5 seconds after commanded ON by PCM, or the voltage stayed at zero for 5 seconds after commanded OFF by PCM.Wiring open circuit/short circuit to ground, shift solenoid, ECM
85TCC solenoid remained ON for 4 seconds after commanded OFF by PCM 90 TCC solenoid voltage stayed high for 2 seconds after commanded ON by PCM, or the voltage stayed at zero for 2 seconds after commanded OFF by PCM.Wiring open circuit/short circuit to ground, transmission mechanical fault, TCC solenoid
86ECM analog/digital – signal errorWiring short to positive, A/C refrigerant pressure sensor, KS, ECT sensor, other DTC codes
87Engine control module (ECM) – EEPROMInsecure EEPROM, incorrect EEPROM, ECM
90Torque converter clutch (TCC) solenoid – circuit malfunctionWiring open circuit/short circuit to ground, TCC solenoid, ECM
91One to Four up-shift lamp control signal showed incorrect potential voltage at PCM for 26 seconds.
95Change oil lamp – circuit malfunctionWiring open circuit/short circuit to ground/short circuit to positive, instrument panel, engine oil level lamp bulb, oil level sensor, ECM
96Engine oil level warning lamp – circuit malfunctionWiring open circuit/short circuit to ground/short circuit to positive, instrument panel, engine oil level lamp bulb, oil level sensor, ECM
97VSS output signal showed incorrect potential voltage at PCM for 26 seconds.Wiring open circuit/short circuit to ground/short circuit to positive, VSS, ECM
98Tach output signal showed incorrect potential voltage at PCM for 26 seconds.ECM
99Invalid ECM programECM
Subscribe
Notify of
guest

This site uses Akismet to reduce spam. Learn how your comment data is processed.

2 Comments
most voted
newest oldest
Inline Feedbacks
View all comments
bill morrow
1 year ago

where are the trouble codes for the CCM, HVAC, SIR & ABS..?
thanks

Marky D
Marky D
2 years ago

Fix for OBD1 Diagnostic Trouble Code 29 [and in some cases, 48] is to perform General Motors Technical Service Bulletin #01-06-04-011 (2002), which:
physically segregates the AIRpump from the intake so the MAF will never see exhaust again
regardless of whether it still works or not, disables the AIRpump permanently
eliminates DTC 29 forever

http://www.skymagik.net/storm/cars/tsb/b-body_010604011.pdf

No LT1 Caprice Roadmaster or Fleetwood should have a pcm calibration which activates the AIRpump.