OBDI Codes
4.3L VIN Z and W
12 – Diagnostic mode
13 - Oxygen sensor circuit - Oxygen sensor voltage stays between 0.35 and 0.55 volts for 30 seconds when the TPS signal was above 0.55 volts. The engine had been running for at least 40 seconds with an engine temperature above 110? F.
14 - Coolant temperature sensor or circuit/ high temperature indicated - Coolant temperature sensor signal indicates a temperature of over 284? F for 4 seconds after the engine had been running for at least 10 seconds.
15 - Coolant temperature sensor or circuit/ low temperature indicated - Coolant temperature sensor signal indicates a temperature colder than -36? F for at least 4 seconds after the engine had been running for 2 seconds.
16 – System voltage high - Charging system voltage was either below 9 volts or above 17 volts for 10 seconds.
17 – Crank Signal Circuit - PCM did not detect any spark reference pulses within 240 fuel control reference pulses (80 crank revolutions) while engine was running below 1200 RPM.
19 – Crankshaft Position Sensor or circuit
21 – Throttle Position Sensor TPS or circuit voltage high - TPS voltage was above 0.8 volts for 5 seconds when engine was running and air flow was less than 15 gm /sec, or the TPS voltage was over 4.8 volts at any time.
22 – Throttle Position Sensor TPS or circuit voltage low - TPS voltage was under 0.2 volts for 4 seconds when the ignition was on.
23 – Intake Air Temperature (IAT) sensor circuit – low temperature indicated - Inlet air temperature sensor signal showed an air temperature of -29? F for 4 seconds.
24 - Vehicle Speed sensor circuit - Vehicle speed sensor signal showed less than 3 MPH for 2 seconds when engine speed was greater than 3000 RPM and transmission has not been in park or neutral for more than 4 seconds. Or vehicle speed goes from above 18 MPH to 0 in less than 2 seconds without applying brake.
25 – Intake Air Temperature (IAT) sensor or circuit – high temperature indicated - Inlet air temperature sensor signal showed an air temperature of over 218? F for 5 seconds when vehicle speed was greater than 35 MPH.
26 - Quad-Driver sense voltage shows a low voltage when battery voltage should be present, or if the sense voltage shows battery voltage when a low voltage should be present for at least 5 seconds when the engine was running.
27 - 2nd gear switch was closed or grounded for 10 seconds when vehicle was in 4th gear, or 2nd or 4th gear switch was open when engine was first started.
28 - 3rd gear switch was closed or grounded for 10 seconds when vehicle was in 4th gear, or 3rd or 4th gear switch was open when engine was first started.
29 - 4th gear switch was closed or grounded for 10 seconds when vehicle was in 4th gear, or 4th gear switch was open when engine was first started.
31 - Park/Neutral Position (PNP) switch circuit - PRNDL indicates a gear other than park or neutral for 13 seconds for 3 consecutive startups when ignition was on, engine was off and vehicle speed was 0. Or the PRNDL status indicators (A, B, C, P) showed an incorrect combination of Lo and Hi for more than 10 seconds.
32 - Exhaust Gas Recirculation (EGR) Circuit - EGR 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 exhaust gas.
33 - MAP sensor signal voltage was too high (low vacuum) for 5 seconds when throttle opening was under 2%.
34 - MAP sensor signal voltage low - MAP sensor signal voltage was too low (high vacuum) when engine speed was over 1200 RPM, or the throttle angle was above 21% when engine speed was over 1200 RPM.
35 - Idle Air Control (IAC) System
38 – Brake Switch
41 – Camshaft Sensor Circuit
42 – Bypass or Electronic Spark Timing circuit - The EST signal did not change when the ECM applied bypass voltage to the ignition module.
43 – Knock Sensor Ciruit - Knock sensor signal was either above 3.5 volts or below 1.5 volts for at least 20 seconds.
44 - Oxygen sensor or circuit – lean exhaust detected. - Oxygen sensor voltage was under 0.25 volts for up to 4 1/2 minutes of closed loop operation.
45 - Oxygen sensor or circuit - rich exhaust detected. - Oxygen sensor voltage was over 0.750 volts for 2 minutes in closed loop operation with a throttle angle between 0.6 and 1.9 volts.
46 – Power Steering Pressure Switch circuit
47 - Momentary loss of power to Body Computer Module (BCM).
48 – Misfire Diagnosis
51 - MEM-CAL, PROM, or ECM Error (Faulty or Incorrect Calibration)
52 – CALPAK or ECM problem
53 – System over-voltage – ECM over 17.7 volts
54 – Fuel Pump Circuit
55 - ECM problem
2.8 VIN R
13 - Oxygen Sensor Open Circuit Open circuit
14 - Coolant Temperature Sensor Circuit High temp indicated
15 - Coolant Temperature Sensor Circuit Low Temp indicated
21 - Throttle Position Sensor (TPS) Circuit (Signal Voltage High)
22 - Throttle Position Sensor (TPS) Circuit (Signal Voltage Low)
24 - VSS Circuit Fault
32 - EGR System Failure
33 - MAP Sensor Circuit Signal Voltage High (Low Vacuum)
34 - MAP Sensor Circuit Signal Voltage Low (High Vacuum)
42 - Electronic Spark Timing (EST)
43 - Electronic Spark Control (ESC) Circuit
44 - Lean Exhaust Indicated
45 - Rich Exhaust Indicated
51 - FAULTY MEM-CAL OR PROM PROBLEM
52 - FUEL CALPAK MISSING
53 - VOLTAGE AT ECM TERMINAL B1 IS GREATER THAN 17.1 VOLTS FOR 2 SECONDS.
54 - Fuel Pump Circuit (Low Voltage)
55 - FAULTY ECM
2.2L VIN 4
13 - Oxygen Sensor Open Circuit Open circuit - Oxygen sensor voltage stays between 0.35 and 0.55 volts for 20 seconds. Engine was at normal operating temperature and had been running for at least 2 minutes after start with a throttle angle above 6%.
14 - Coolant Temperature Sensor Circuit High temp indicated - Coolant temperature sensor signal indicates a temperature above 285? F after the engine has been running for at least 2 minutes.
15 - Coolant Temperature Sensor Circuit Low Temp indicated - Coolant temperature sensor signal indicates a temperature colder than -38? F after the engine has been running for at least 1 minute.
21 - Throttle Position Sensor (TPS) Circuit (Signal Voltage High) - TPS voltage was above 3.9 volts for 5 seconds when the MAP sensor signal showed manifold vacuum to be 15 pounds or more and engine speed was less than 1750 RPM or TPS voltage was below 1.9 volts for 64 seconds.
22 - Throttle Position Sensor (TPS) Circuit (Signal Voltage Low) - TPS voltage was under 0.21 volts for 5 seconds when the engine was running.
23 – Intake Air Temperature (IAT) sensor circuit – low temperature indicated - Inlet Air Temperature Sensor signal showed an air temperature below -30? F or above 302? F for more than 2 seconds after the engine has been running for 2 minutes.
24 - VSS Circuit Fault - Vehicle speed sensor signal showed less than 3 MPH for 2 seconds when engine speed was greater than 3000 RPM and transmission has not been in park or neutral for more than 4 seconds. Or vehicle speed goes from above 18 MPH to 0 in less than 2 seconds without applying brake.
25 – Intake Air Temperature (IAT) sensor circuit – high temperature indicated - Inlet Air Temperature Sensor signal showed an air temperature over 304? F after the engine has been running for 5 minutes and 20 seconds and the vehicle speed was greater than 15 MPH.
26 – Quad Module Driver Circuit - Quad-Driver sense voltage shows a low voltage when battery should be present or the sense voltage shows battery voltage when a low voltage should be present for at least 20 seconds.
27 – Quad Module Driver Circuit - Quad-Driver sense voltage shows a low voltage when battery should be present or the sense voltage shows battery voltage when a low voltage should be present for at least 20 seconds.
28 – Quad Module Driver Circuit - Quad-Driver sense voltage shows a low voltage when battery should be present or the sense voltage shows battery voltage when a low voltage should be present for at least 20 seconds.
29 – Quad Module Driver Circuit - Quad-Driver sense voltage shows a low voltage when battery should be present or the sense voltage shows battery voltage when a low voltage should be present for at least 20 seconds.
32 - EGR System Failure - EGR 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 exhaust gas.
33 - MAP Sensor Circuit Signal Voltage High (Low Vacuum) - MAP sensor signal voltage was too high for 10 seconds when throttle opening was under 12%.
34 - MAP Sensor Circuit Signal Voltage Low (High Vacuum) - When engine speed was between 1700 and 3600 RPM and throttle position angle was less than 1%, the MAP signal showed low voltage (high manifold vacuum) for at least 5 seconds.
43 - Electronic Spark Control (ESC) Circuit - The ECM did not detect a knock signal during near wide open throttle operation, or the knock signal was present for 3.5 seconds or more during normal engine operation.
44 - Lean Exhaust Indicated - Oxygen sensor voltage was under 0.3 volts for 50 seconds of closed loop operation. Throttle angle was above 5%.
45 - Rich Exhaust Indicated - Oxygen sensor voltage was over 0.700 volts for at least 51 seconds of closed loop operation. Throttle angle was above 5% and engine had been running for at least 2 minutes.
51 - FAULTY MEM-CAL OR PROM PROBLEM
53 – System Over-Voltage - Battery voltage was higher than 17.1 volts for 0.2 seconds, or below 10 volts for 4 minutes.
54 - Fuel Pump Circuit (Low Voltage)
55 – Fuel Lean Monitor - Oxygen sensor voltage was less than 0.3 volts for 5 seconds of closed loop operation.
66 – A/C Pressure Switch or Circuit - A/C refrigerant pressure voltage was either less than 0.19 volts or greater than 4.9 volts for 15 seconds, or the pressure voltage was above 4.0 volts when A/C clutch was not requested.