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Makes 🢒 GMC_Truck 🢒 1998 🢒 GMC P42 Commercial Chassis 🢒 Transmission/Transaxle 🢒 Automatic Transmission - 4L80-E 🢒 Diagnostic Trouble Code Identification

Diagnostic Trouble Code Identification Gas VCM

Diagnostic Trouble Code (DTC) Identification Diagnostic Types

DTC

Description

DTC Type

Default Action

P0218

Transmission Fluid Overtemperature

D
    • The VCM freezes shift adapts.
    • DTC P0218 is stored in the VCM history.

P0502

Vehicle Speed Sensor Circuit -- Low Input

D / B
    • The VCM illuminates the MIL for California emissions.
    • The VCM freezes shift adapts.
    • The VCM commands maximum line pressure
    • The VCM defaults a calculated OSS from the A/T ISS Sensor output.
    • DTC P0502 is stored in the VCM history.

P0503

Vehicle Speed Sensor Circuit -- Intermittent

D / B
    • The VCM illuminates the MIL for California emissions.
    • The VCM freezes shift adapts.
    • The VCM commands maximum line pressure
    • The VCM defaults a calculated OSS from the A/T ISS Sensor output.
    • DTC P0503 is stored in the VCM history.

P0560

System Voltage Malfunction

D
    • The VCM commands an immediate landing to second gear.
    • The VCM freezes shift adapts.
    • The VCM turns off all transmission output devices
    • DTC P0560 is stored in VCM history

P0711

Automatic Transmission Fluid Temperature (TFT) Sensor Circuit Range/Performance

D
    • The VCM freezes shift adapts.
    • The VCM defaults the TFT to 140°C
        (284°F).
    • DTC P0711 is stored in the VCM history.

P0712

Transmission Fluid Temperature Sensor Circuit -- Low Input

D
    • The VCM freezes shift adapts
    • The VCM defaults TFT to 140°C (284°F) for shift scheduling (hot mode pattern)
    • DTC P0712 is stored in VCM history

P0713

Transmission Fluid Temperature Sensor Circuit -- High Input

D
    • The VCM freezes shift adapts.
    • The VCM defaults TFT to 140°C (284°F) for shift scheduling (hot mode pattern)
    • DTC P0713 is stored in VCM history.

P0716

Input Speed Sensor Circuit -- Intermittent

D / B
    • The VCM illuminates the MIL for California emissions.
    • The VCM freezes shift adapts.
    • The VCM commands maximum line pressure
    • DTC P0716 is stored in VCM history.

P0717

Input Speed Sensor Circuit -- Low Input

D / B
    • The VCM illuminates the MIL for California emissions.
    • The VCM freezes shift adapts.
    • The VCM commands maximum line pressure.
    • DTC P0717 is stored in VCM history.

P0719

Brake Switch Circuit -- Low Input

D

DTC P0719 is stored in VCM history.

P0724

Brake Switch Circuit -- High Input

D

DTC P0724 is stored in VCM history.

P0730

Incorrect Gear Ratio

D
    • The VCM commands maximum line pressure.
    • The VCM freezes shift adapts.
    • DTC P0730 is stored in VCM history

P0741

Torque Converter Clutch System Stuck Off

D / B
    • The VCM illuminates the MIL for California emissions.
    • The VCM inhibits TCC engagement.
    • The VCM inhibits fourth gear engagement.
    • DTC P0741 is stored in VCM history.

P0742

Torque Converter Clutch System Stuck On

D / B
    • The VCM illuminates the MIL for California emissions.
    • The VCM commands maximum line pressure.
    • The VCM freezes shift adapts.
    • DTC P0742 is be stored in VCM history.

P0748

Pressure Control Circuit -- Electrical

D
    • The VCM disables the PC Sol. Valve.
    • The VCM freezes shift adapts.
    • DTC P0748 is stored in VCM history.

P0751

1-2 Shift Solenoid Valve -- Performance

D / B
    • The VCM illuminates the MIL for California emissions.
    • The VCM commands maximum line pressure.
    • The VCM freezes shift adapts.
    • 3-2 downshifts above 25 MPH are inhibited.
    • DTC P0751 is stored in VCM history.

P0753

1-2 Shift Solenoid Valve Circuit -- Electrical

D/A
    • The VCM illuminates the MIL for California emissions.
    • The VCM freezes shift adapts.
    • 3-2 downshifts above 25 MPH are inhibited.
    • The VCM commands maximum line pressure.
    • DTC P0753 is stored in VCM history.

P0756

2-3 Shift Solenoid Valve -- Performance

D / A
    • The VCM illuminates the MIL for California emissions.
    • The VCM commands an immediate landing to second gear.
    • The VCM freezes shift adapts.
    • The VCM commands maximum line pressure.
    • DTC P0756 is stored in VCM history.

P0758

2-3 Shift Solenoid Valve Circuit-- Electrical

D / A
    • The VCM illuminates the MIL for California emissions.
    • The VCM commands maximum line pressure.
    • The VCM freezes shift adapts.
    • The VCM commands an immediate landing to second gear.
    • DTC P0758 is stored in VCM history

P1810

Automatic Transmission Fluid Pressure Manual Valve Position Switch Circuit Malfunction

D / B
    • The VCM illuminates the MIL for California emissions.
    • The VCM freezes shift adapts.
    • The VCM assumes D4 shift pattern.
    • The VCM commands maximum line pressure.
    • The VCM forces TCC apply when fourth gear is commanded.
    • DTC P1810 is stored in VCM history.

P1860

Torque Converter Clutch Pulse Width Modulation Solenoid Valve Circuit-Electrical

D / A
    • The VCM illuminates the MIL for California emissions.
    • The VCM inhibit s TCC engagement.
    • The VCM inhibits fourth gear engagement.
    • The VCM freezes shift adapts.
    • DTC P1860 is stored in VCM history

P1870

Transmission Component Slipping

D / B
    • The VCM illuminates the MIL for California emissions.
    • The VCM commands maximum line pressure.
    • The VCM inhibits TCC engagement.
    • The VCM inhibits fourth gear engagement.
    • The VCM freezes shift adapts.
    • DTC P1870 is stored in VCM history.

P1875

Four-Wheel Drive Low Switch Circuit Electrical

D / B
    • The VCM illuminates the MIL for California emissions.
    • The VCM freezes shift adapts.
    • The VCM assumes a 4WD Lo state if the switch fails when open, or the VCM assumes a 4WD High state if the switch fails when closed, for a transmission shift pattern.
    • The VCM inhibits fourth gear engagement.
    • The VCM freezes shift adapts.
    • DTC P1875 is stored in VCM history.

DTC Types:

Diagnostic Trouble Code Identification Diesel PCM

Diagnostic Trouble Code (DTC) Identification Diagnostic Types

DTC

Description

DTC Type

Default Action

P0218

Transmission Fluid Overtemperature

D
    • The PCM freezes shift adapts.
    • DTC P0218 is stored in the PCM history.

P0560

System Voltage Malfunction

D
    • The PCM inhibits TCC engagement.
    • The PCM freezes shift adapts.
    • The PCM turns off the PC Sol. Valve.
    • The PCM commands an immediate landing into 2nd gear.
    • DTC P0560 is stored in PCM history.

P0711

Transmission Fluid Temperature Sensor Circuit Range/Performance

D
    • The PCM uses a TFT default value of 140°C (284°F).
    • The PCM freezes shift adapts.
    • DTC P0711 is stored in the PCM history.

P0712

Transmission Fluid Temperature Sensor Circuit -- Low Input

D
    • The PCM freezes shift adapts.
    • The PCM uses a TFT default value of 140°C (284°F).
    • DTC P0712 is stored in PCM history.

P0713

Transmission Fluid Temperature Sensor Circuit -- High Input

D
    • The PCM freezes shift adapts.
    • The PCM uses a TFT default value of 140°C (284°F).
    • DTC P0713 is stored in PCM history.

P0716

Input Speed Sensor Circuit -- Intermittent

B
    • The PCM illuminates the MIL.
    • The PCM freezes shift adapts.
    • The PCM commands maximum line pressure
    • DTC P0716 is stored in PCM history.

P0717

Input Speed Sensor Circuit -- Low Input

B
    • The PCM illuminates the MIL.
    • The PCM freezes shift adapts.
    • The PCM commands maximum line pressure.
    • DTC P0717 is stored in PCM history.

P0719

Brake Switch Circuit -- Low Input

D

DTC P0719 is stored in PCM history.

P0722

Output Speed Sensor -- Low Input

B
    • The PCM illuminates the MIL.
    • The PCM freezes shift adapts.
    • The PCM commands maximum line pressure.
    • The PCM calculates OSS from ISS.
    • DTC P0722 is stored in the PCM history.

P0723

Output Speed Sensor Intermittent

B
    • The PCM illuminates the MIL.
    • The PCM freezes shift adapts.
    • The PCM commands maximum line pressure.
    • The PCM calculates OSS from ISS.
    • DTC P0723 is stored in the PCM history.

P0724

Brake Switch Circuit -- High Input

D
    • Apply TCC if APP is greater than 0.5% and the vehicle speed is greater than 30 mph.
    • DTC P0724 is stored in VCM history.

P0730

Incorrect gear ratio

D
    • The PCM commands maximum line pressure.
    • The PCM freezes shift adapts.
    • DTC P0730 is stored in PCM history.

P0741

Torque Converter Clutch System Stuck Off

B
    • The PCM illuminates the MIL.
    • The PCM inhibits TCC engagement.
    • The PCM inhibits fourth gear engagement.
    • The PCM commands increased line pressure.
    • DTC P0741 is stored in PCM history.

P0742

Torque Converter Clutch System Stuck On

B
    • The PCM illuminates the MIL.
    • The PCM freezes shift adapts.
    • The PCM commands maximum line pressure.
    • DTC P0742 is stored in PCM history.

P0748

Pressure Control Solenoid Circuit -- Electrical

D
    • The PCM freezes shift adapts.
    • The PCM commands maximum line pressure by disabling the PC Sol. Valve.
    • DTC P0748 is stored in PCM history.

P0751

1-2 Shift Solenoid Valve --Performance

B
    • The PCM illuminates the MIL.
    • The PCM freezes shift adapts.
    • The PCM commands maximum line pressure.
    • DTC P0751 is stored in PCM history.

P0753

1-2 Shift Solenoid Valve -- Electrical

A
    • The PCM illuminates the MIL.
    • The PCM freezes shift adapts.
    • The PCM commands maximum line pressure.
    • MIL.
    • DTC P0753 is stored in PCM history.

P0756

2-3 Shift Solenoid Valve -- Performance

A
    • The PCM illuminates the MIL.
    • The PCM commands an immediate landing into second gear.
    • The PCM freezes shift adapts.
    • The PCM commands maximum line pressure.
    • DTC P0756 is stored in PCM history.

P0758

2-3 Shift Solenoid Valve -- Electrical

A
    • The PCM illuminates the MIL.
    • The PCM commands an immediate landing to second gear.
    • The PCM freezes shift adapts.
    • The PCM commands maximum line pressure.
    • DTC P0758 is stored in the PCM history

P1810

Transmission Fluid Pressure Manual Valve Position Switch Assembly -- Circuit Malfunction

B
    • The PCM illuminates the MIL.
    • The PCM freezes shift adapts.
    • The PCM assumes a D4 shift pattern.
    • The PCM commands maximum line pressure.
    • The PCM commands TCC apply with 4th gear commanded ON.
    • DTC P1810 is stored in PCM history.

P1811

Maximum Adapt and Long Shift

D
    • The PCM freezes shift adapts.
    • The PCM commands maximum line pressure.
    • DTC P1811 is stored in PCM history.

P1860

Torque Converter Clutch Pulse Width Modulation Solenoid Circuit -- Electrical

A
    • The PCM illuminates the MIL.
    • The PCM inhibits TCC engagement.
    • The PCM inhibits fourth gear engagement.
    • The PCM freezes shift adapts.
    • DTC P1860 is stored in PCM history

P1870

Transmission Component Slipping

B
    • The PCM illuminates the MIL.
    • The PCM commands maximum line pressure.
    • The PCM inhibits TCC engagement.
    • The PCM inhibits fourth gear engagement.
    • The PCM freezes shift adapts.
    • DTC P1870 is stored in PCM history.

P1875

Four-Wheel Drive Low Switch Circuit -- Electrical

B
    • The PCM illuminates the MIL.
    • The PCM freezes shift adapts.
    • The PCM assumes a 4WD Lo state if the switch fails when open, or the PCM assumes a 4WD High state if the switch fails when closed, for a transmission shift pattern.
    • DTC P1875 is stored in PCM history.

DTC Types:

Diagnostic Trouble Code Identification Diesel TCM

Diagnostic Trouble Code (DTC) Identification Diagnostic Types

DTC

Description

Default Action

21

Throttle Position Sensor Circuit High Voltage
    • Set line pressure to maximum
    • Use 35% throttle as a default
    • Inhibit fourth gear if in Hot Mode
    • DTC 21 is stored in TCM history.

22

Throttle Position Sensor Circuit Low Voltage
    • Set line pressure to maximum
    • Use 35% throttle as a default
    • Inhibit fourth gear if in Hot Mode
    • DTC 22 is stored in TCM history.

24

Output Shaft Speed (OSS) Sensor Low
    • Set line pressure to maximum
    • Allow 4-3, 3-2, and 1-2 shifts, then maintain second gear
    • Calculate output speed from input speed
    • DTC 24 is stored in TCM history.

28

TFP Valve Position Switch
    • Assume Drive 4 is selected
    • Inhibit fourth gear if in Hot Mode
    • Inhibit TCC operation
    • DTC 28 is stored in TCM history.

37

TCC Brake Switch Low Input
    • No TCC
    • No fourth gear if in Hot Mode
    • DTC 37 is stored in TCM history.

38

TCC Brake Switch High Input
    • No TCC
    • No fourth gear if in Hot Mode
    • DTC 38 is stored in TCM history.

39

Torque Converter Clutch (TCC) Stuck OFF
    • Inhibit fourth gear if in Hot Mode
    • DTC 39 is stored in TCM history.

51

Prom Error

DTC 51 is stored in TCM history.

52

System Voltage High Long
    • Maximum line pressure
    • 2nd gear landing
    • Inhibit TCC
    • DTC 52 is stored in TCM history.

53

System Voltage High
    • Maximum line pressure
    • 2nd gear only
    • Inhibit TCC operation
    • DTC 53 is stored in TCM history.

58

Transmission Fluid Temperature (TFT) Sensor Circuit High
    • TCC in second, third, and fourth gears
    • Maximum line pressure
    • Defaults to 140°C TFT
    • DTC 58 is stored in TCM history.

59

Transmission Fluid Temperature (TFT) Sensor Circuit Low
    • TCC in second, third, and fourth gears
    • Maximum line pressure
    • Defaults to 140°C TFT
    • DTC 59 is stored in TCM history.

63

BARO Sensor Circuit High
    • No altitude compensation of shift patterns
    • DTC 63 is stored in TCM history.

64

BARO Sensor Circuit Low
    • No altitude compensation of shift patterns
    • DTC 64 is stored in TCM history.

68

Transmission Component Slipping
    • Inhibit TCC operation
    • Inhibit manual mode operation
    • DTC 68 is stored in TCM history.

69

Torque Converter Clutch (TCC) Stuck ON

DTC 69 is stored in TCM history.

71

Camshaft Position Sensor (CMP) Circuit Low (Engine Speed Sensor)
    • The TCM inhibits TCC
    • DTC 71 is stored in TCM history.

72

Transmission Output Shaft Speed (OSS) Sensor Circuit Loss
    • Maximum line pressure
    • Soft landing into second gear
    • DTC 72 is stored in TCM history.

73

Pressure Control Solenoid (PC Sol.) Valve Electrical
    • Maximum line pressure
    • DTC 73 is stored in TCM history.

74

Automatic Transmission Input Shaft Speed (A/T ISS) Sensor Circuit
    • The TCM inhibits TCC
    • DTC 74 is stored in TCM history.

75

System Voltage Low
    • Turn pressure control solenoid OFF
    • Allow 4-3, 3-2, and 1-2 shifts, then maintain second gear
    • Inhibit TCC and fourth gear
    • DTC 75 is stored in TCM history.

79

Transmission Fluid Overtemperature

DTC 79 is stored in TCM history.

81

2-3 Shift Solenoid (2-3 SS) Valve Circuit Fault
    • Inhibit TCC operation
    • Maximum line pressure
    • DTC 81 is stored in TCM history.

82

1-2 Shift Solenoid (1-2 SS) Valve Circuit Fault
    • Second and third gears only
    • Maximum line pressure
    • DTC 82 is stored in TCM history.

83

TCC PWM Solenoid Valve Circuit Fault
    • Inhibit fourth gear if in Hot Mode
    • Inhibit TCC operation
    • DTC 83 is stored in TCM history.

85

Undefined Gear Ratio
    • Maximum line pressure
    • Inhibit TCC
    • DTC 85 is stored in TCM history.

86

Low Ratio Error
    • Defaults to second gear
    • Maximum line pressure
    • Inhibits TCC
    • DTC 86 is stored in TCM history.

87

High Ratio Error
    • Landing to second gear
    • Maximum line pressure
    • Inhibits TCC
    • DTC 87 is stored in TCM history.