| 94-95 3.1L VIN M |
|---|
| Flash Code | Fault Location | Probable Cause |
| 11 | Malfunction indicator lamp (MIL) – cirucit malfunction | Wiring open circuit/short circuit to ground, MIL, supply wire, ECM |
| 12 | Start of diagnosis | No engine speed (RPM) signal received) |
| 13 | Oxygen sensor voltage stays between 0.35 and 0.55 volts for 30 seconds
when the TPS signal was above 3%. The engine had been operating in a closed
loop with an engine temperature above 149° F. | Wiring open circuit, O2S/HO2S, ECM |
| 14 | Coolant temperature sensor signal indicates a temperature of over 275°
F after the engine had been running for at least 10 seconds. | Wiring short circuit to ground, ECT sensor, ECM |
| 15 | Coolant temperature sensor signal indicates a temperature colder than
-38° F for 2 seconds. | Wiring open circuit to ground, ECT sensor, ECM |
| 16 | Charging system voltage was below 8 volts for 5 seconds when engine speed
was above 1000 RPM. | Wiring, alternator, ECM |
| 17 | PCM did not detect any cam reference pulses for 3 seconds while engine
was running. | Wiring open circuit/short circuit to ground/short circuit to positive, mechanical fault, CMP sensor, ECM |
| 18 | Injector(s) – circuit malfunction | Wiring open circuit/short circuit to ground, supply wire, injectors, ECM |
| 19 | 7X reference – circuit malfunction | Wiring, mechanical fault, CKP sensor, PROM, ECM |
| 21 | TPS voltage was above 3.8 volts for 5 seconds when engine was running
above 600 RPM. | Wiring open circuit/short circuit to positive, TP sensor, ECM |
| 22 | TPS voltage was under 0.2 volts for 3 seconds when the engine was running
at 400 RPM or more. | Wiring open circuit/short circuit to ground, TP sensor, ECM |
| 23 | Inlet air temperature sensor signal showed an air temperature of -36°
F for 4 minutes. | Wiring open circuit, IAT sensor, ECM |
| 24 | Vehicle speed sensor signal showed less than 5 MPH for 4 seconds when
engine speed was greater than 3000 RPM and transmission was not in park
or neutral. | Wiring open circuit/short circuit, PROM, VSS, ECM |
| 25 | Inlet air temperature sensor signal showed an air temperature over 297
F for 5 seconds when I vehicle speed was greater than 1 MPH. | Wiring short circuit to ground, IAT sensor, ECM |
| 26 | Engine control module quad driver/output driver | Wiring open circuit/short circuit to ground/short circuit to positive, ECM controlled components, ECM * (see below for additional details) |
| 27 | Exhaust gas recirculation (EGR) vacuum control – circuit malfunction | Wiring open/short circuit to ground/short circuit to positive, EGR valve, ECM |
| 28 | Transaxle range switch had incorrect signal for 10 seconds. | Wiring open circuit/short circuit to ground, transmission range switch, ECM |
| 29 | Secondary air injection (AIR) system | Wiring open circuit/short circuit to ground/short circuit to positive, AIR valve relay, ECM |
| 31 | Park/neutral position (PNP) switch | Wiring open circuit/short circuit to ground, incorrectly adjusted, PNP switch, ECM |
| 32 | Digital EGR calibrated response in manifold pressure was not seen by ECM. | Wiring open circuit/short circuit to ground, exhaust system blocked, EGR valve, ECM |
| 33 | MAP sensor signal voltage was too high (low vacuum) for 4 seconds when
throttle angle was between 3% and 30% and held steady. | Wiring open circuit/short circuit to positive, hose blocked/leaking, MAP sensor, ECM |
| 34 | MAP sensor signal voltage was too low (high vacuum) for 2.5 seconds when
engine speed was above 500 RPM. | Wiring open circuit/short circuit to ground, MAP sensor, ECM |
| 35 | Idle speed was either above or below desired idle by 350 RPM for 50 seconds. | Wiring open circuit/short circuit to ground/short circuit to positive, intake system leaking, mechanical fault, IAC valve, ECM |
| 36 | PCM did not detect 6 or more consecutive 24X (crank reference) pulses. | Wiring open circuit/short circuit to ground, CKP sensor, ECM |
| 37 | PCM did not receive the TCC brake signal 4 consecutive times when vehicle
speed went from above 35 MPH (for at least 10 seconds) to 0 MPH. | Wiring open circuit/short circuit to ground/short circuit to positive, TCC brake switch, ECM |
| 38 | Brake pedal position (BPP) switch | Wiring open circuit/short circuit to ground/short circuit to positive, BPP switch, BPP switch incorrectly adjusted, ECM |
| 39 | Torque converter clutch (TCC) – circuit malfunction | Wiring open circuit, BPP switch, TCC solenoid, TCC switch, 3rd gear switch, mechanical fault, ECM |
| 41 BUICK Skylark | Camshaft position (CMP) sensor | Wiring open circuit/short circuit to ground, CMP sensor, ICM, ECM |
| 41 | The EST signal was present when the circuit should have been grounded
by the ignition module when it received bypass voltage under 1 volt. | Wiring, poor connections, ICM, ECM |
| 42 | The EST signal did not change when the ECM applied bypass voltage to the
ignition module. | Wiring open circuit/short circuit to ground, ICM, ECM |
| 43 | The ECM detected knock sensor voltage above 4.6 volts or below 0.84 volts
for 10 seconds during hard acceleration with engine speed between 3400 and
4400 RPM. | Wiring open circuit/short circuit to ground/short to positive, KS, PROM, ECM |
| 44 | Oxygen sensor voltage was under 0.25 volts for 60 seconds of closed loop
operation. | Wiring short circuit to ground, fuel pressure low, fuel contamination, exhaust system leaking, O2S/HO2S, ECM |
| 45 | Oxygen sensor voltage was over 0.75 volts for 60 seconds of closed loop
operation. | Fuel pressure high, injector(s) leaking, shield wiring open circuit, O2S contamination, EVAP canister purge valve, TP sensor, MAP sensor, EGR system, excessive fuel in engine oil, ECM |
| 46 | Immobilizer control module – fuel enable signal | Incorrect ignition key, wiring open circuit/short circuit to ground, immobilizer control module, ECM |
| 47 | Body control module (BCM), CAN data bus – communication malfunction | Wiring, PROM, BCM |
| 48 | Mass air flow (MAF) sensor – circuit malfunction | Wiring open circuit/short circuit to ground/short circuit to positive, MAF sensor, ECM |
| 50 | System voltage low | Wiring open circuit/short circuit to ground, alternator, ECM |
| 51 | PROM error. | Insecure PROM, incorrect PROM, ECM |
| 53 | Charging system voltage was greater than 16.5 volts. | Alternator, ECM |
| 54 | Fuel pump voltage was above 14 volts or less than 7 volts for 3 seconds. | Wiring open circuit/short circuit to ground, fuel pump relay, fuel pump, engine oil pressure warning lamp switch, ECM |
| 55 | Engine control module (ECM) | Ground wiring open circuit, insecure PROM, ECM |
| 58 | Immobilizer control module – fuel enable signal | Incorrect ignition key, wiring open circuit/short circuit to ground/short circuit to positive, immobilizer control module, ECM |
| 59 | Transmission fluid temperature (TFT) sensor – low temperature indicated | Wiring open circuit, TFT sensor, ECM |
| 61 | Cruise control vent solenoid | Wiring open circuit/short circuit to ground/short circuit to positive, cruise control servo, ECM |
| 62 | Cruise control vacuum solenoid | Wiring open circuit/short circuit to ground/short circuit to positive, cruise control servo, ECM |
| 63 | Heated oxygen sensor (HO2S) bank 2 – open circuit | Wiring open circuit/short circuit to ground/short circuit to positive, HO2S, HO2S contamination, ECM |
| 64 | Heated oxygen sensor (HO2S) bank 2 – mixture lean | Wiring short circuit to ground, injector(s) blocked, fuel contamination, fuel pressure low, exhaust system leaking, ECM |
| 65 | Cruise control servo position sensor – circuit malfunction | Wiring open circuit/short circuit to ground/short circuit to positive, cruise control servo, ECM |
| 66 | A/C refrigerant pressure sensor – low pressure | Wiring open circuit, A/C refrigerant pressure sensor, ECM |
| 67 | Cruise control switch – circuit malfunction | Wiring open circuit/short circuit to positive, cruise control switch, brake pedal vacuum valve, ECM |
| 68 | Cruise control servo – servo position sensor high | Hoses blocked, brake pedal vacuum valve, cruise control servo, cruise control cable binding |
| 69 | A/C compressor clutch relay – circuit malfunction | Wiring open circuit, A/C compressor clutch relay, ECM |
| 70 | A/C refrigerant pressure sensor – high pressure | Wiring open circuit/short circuit to positive, A/C refrigerant pressure sensor, ECM |
| 72 | Vehicle speed sensor indicated a sudden change in speed of more than 33
MPH in 2 seconds when vehicle was in gear. | Wiring open circuit/short circuit to ground, VSS, ECM |
| 73 | Pressure control solenoid – circuit malfunction | Wiring open circuit/short circuit to ground/short to positive, ECM |
| 75 | Digital EGR solenoid 1 failed 3 consecutive times. Engine speed was between
1400 and 2000 RPM when throttle angle was 0% and the MAP sensor showed high
manifold vacuum. | Wiring open circuit/short circuit to ground, supply wire, EGR valve, ECM |
| 76 | Digital EGR solenoid 2 failed 3 consecutive times. Engine speed was between
1400 and 2000 RPM when throttle angle was 0% and the MAP sensor showed high
manifold vacuum. | Wiring open circuit/short circuit to ground, supply wire, EGR valve, ECM |
| 77 | Digital EGR solenoid 3 failed 3 consecutive times. Engine speed was between
1400 and 2000 RPM when throttle angle was 0% and the MAP sensor showed high
manifold vacuum. | Wiring open circuit/short circuit to ground, supply wire, EGR valve, ECM |
| 78 | Engine coolant blower motor relay 2 – circuit malfunction | Wiring open circuit/short circuit to ground/short circuit to positive, engine coolant blower motor relay, ECM |
| 79 | Transmission fluid – overtemp | Wiring open circuit/short circuit to ground, TFT sensor, ECM |
| 80 | Transmission component – slipping | Wiring open circuit/short circuit to ground/short circuit to positive, TR pressure switch, transmission mechanical fault, ECM |
| 81 | Transmission shift solenoid (SS), 2nd-3rd – circuit malfunction | Wiring open circuit/short circuit to ground, shift solenoid, ECM |
| 82 | 3X reference pulses were not detected by PCM during cranking. | Wiring open circuit/short circuit to ground, CKP sensor, ICM, ECM |
| 83 | Torque converter clutch (TCC) solenoid, pulse width modulated – circuit malfunction | Wiring open circuit/short circuit to ground/short circuit to positive, CKP sensor, TCC solenoid, ECM |
| 84 | Transmission shift solenoid (SS), 3rd-2nd – circuit malfunction | Wiring open circuit/short circuit to ground, shift solenoid, ECM |
| 85 | Engine control module (ECM) – PROM | Insecure PROM, incorrect PROM, ECM |
| 86 | ECM analog/digital – signal error | Wiring short to positive, A/C refrigerant pressure sensor, KS, ECT sensor, other DTC codes |
| 87 | Engine control module (ECM) – EEPROM | Insecure EEPROM, incorrect EEPROM, ECM |
| 90 | TCC solenoid voltage stayed high for 2 seconds after it was turned ON
by the PCM, or the TCC solenoid voltage was 0 volts for 2 seconds after
it was turned OFF by the PCM. | Wiring open circuit/short circuit to ground, TCC solenoid, ECM |
| 95 | Change oil lamp – circuit malfunction | Wiring open circuit/short circuit to ground/short circuit to positive, instrument panel, engine oil life lamp bulb, ECM |
| 96 | Transmission system – voltage low | Wiring open circuit, alternator, ECM |
| 97 | Vehicle speed sensor (VSS) – circuit malfunction | Wiring open circuit/short circuit to ground/short circuit to positive, VSS, ECM |
| 98 | Invalid ECM program | ECM |
| 99 | Invalid ECM program | ECM |
