GM GM 91 4.9L VIN B Trouble Code Info


91 4.9L VIN B
12 PCM did not receive distributor reference pulses for 4 seconds.
13 Oxygen sensor voltage stays between 0.307 and 0.609 volts for 64 seconds. Engine was at normal operating temperature at a speed over 800 RPM.
14 Coolant temperature sensor signal indicates a temperature of over 311° F.
15 Coolant temperature sensor signal indicates a temperature colder than -27° F.
16 Ignition voltage was either less than 10 volts or greater than 16 volts for 5 seconds.
19 Fuel pump feedback voltage stayed above 7 volts for 4 seconds after ignition was turned on.
20 Fuel pump feedback voltage was 2 volts or less for 1 second.
21 TPS value was 72 degrees or more for 0.7 seconds.
22 TPS value was 1.3 degrees or less for 0.7 seconds when the engine was running at 600 RPM or more.
23 EST signal did not change when the ECM applied bypass voltage to the ignition module.
24 Vehicle speed was 0 for 3 seconds with transmission in drive or reverse and brake off when throttle angle was at least 17 degrees and engine RPM was 1400 or greater.
26 Throttle switch input to the PCM was closed for 1.8 seconds while the TPS was between 20 and 75 degrees.
27 Throttle switch on the ISC motor never closed during idle operation.
30 TPS was 14 degrees or more while ISC was retracting for 15 seconds, or TPS was 2 degrees while ISC was extending for 15 seconds.
31 MAP sensor was shorted to 5 volts for 0.2 seconds.
32 MAP sensor was open showing a reading of 0.5 volts or less for 0.2 seconds.
34 MAP sensor signal voltage was too high (low vacuum) for 15 seconds when throttle switch was closed.
37 MAT sensor was shorted showing a temperature of 313° F or more.
38 MAT sensor was open showing a temperature of -27° F or less.
39 Engine RPM was outside of the range expected for indicated vehicle speed indicating a VCC engagement problem.
40 Power steering switch was open when vehicle speed was 45 MPH or more.
41 CAM reference pulses were not received when distributor reference pulses were received for 5 seconds at an engine speed of 1600 RPM or less.
44 Oxygen sensor was lean for more than 50 seconds.
45 Oxygen sensor was rich for more than 50 seconds.
47 ECM has received bad data from BCM for 5 seconds while engine speed was 500 RPM or more.
48 EGR open 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. Vehicle speed was over 35 MPH and engine was warm.
52 ECM has lost primary battery power.
53 Distributor reference pulses were not received for 0.4 seconds.
55 TPS zero point was out of range.
58 Pass Key fuel enable was not correct.
60 Transmission was not in drive when cruise control was engaged.
61 Cruise vent solenoid commanded OFF but solenoid remained ON, or commanded ON but solenoid remained OFF.
62 Cruise vacuum solenoid commanded OFF but solenoid remained ON, or commanded ON but solenoid remained OFF.
63 Vehicle speed was 20 MPH higher than the set speed for 0.5 seconds when cruise control was on.
64 Vehicle speed increased more than 16 MPH in 1 second while cruise control was engaged.
65 Cruise control servo position was 6.3% or less for 1 second.
66 Engine RPM was 4800 or more for 0.25 seconds with cruise control engaged.
67 Cruise control Set/Coast or Resume/Accel switch was closed for 10 minutes.
68 With cruise control engaged the throttle angle was greater than 20 degrees and servo position sensor indicated a stroke greater than commanded for 2 seconds.
70 Throttle position changed too rapidly without a corresponding change in MAP sensor signal when engine was running.
71 MAP sensor signal changed too rapidly while TPS signal was steady and engine speed did not change.
73 Coolant temperature sensor voltage has changed 0.3 volts in 1 second.
74 MAT sensor signal changed 0.3 volts or more in 0.25 seconds.
75 Vehicle speed changed by 8 MPH or more in 1 second while MAP sensor remained steady with engine running and brakes not applied.
80 Block learn was 104 or less for 25 seconds with a throttle angle between 6 degrees and 30 degrees and engine was warm.
85 The coast down throttle angle offset is more than 5 degrees from the zero value.
90 Vehicle speed cycles from 30 MPH to 0 at least 10 consecutive times with no VCC brake switch input.
91 Gear selector switch has either an open or a short causing an invalid signal for a forward or reverse gear.
92 Heated window signal was present at PCM for 10 minutes or more.
96 Throttle angle was 65 degrees or more for 12 seconds with transmission in drive or reverse and vehicle speed was 5 MPH or less with brake being applied.
97 Gear selector was moved from park or neutral to drive or reverse with engine speed over 2000 RPM but under 6 MPH.
98 At a vehicle speed under 6 MPH, the gear selector was moved from park or neutral into drive or reverse when engine speed was 600 RPM greater than determined by PCM.
99 Servo position sensor indicated that servo was still engaged after cruise control had been disengaged for 2 seconds. Throttle angle was above 20 degrees.