Transmission Control Module
Runs the automatic gearbox — shift scheduling, line pressure, torque converter lock-up — using engine load and road speed from the engine module. When it detects an internal fault it drops into a protective default, usually a single fixed gear with no lock-up, which is meant to get the vehicle home rather than to be driven on: an unlocked converter generates heat the cooler was not sized for.
Also known as: tcm, tcu, gearbox ecu, transmission ecu, gearbox control module
Referenced by 485 codes
Codes involving this component (485)
- P0613 Transmission Control Module Processor High
- P0614 Engine Control Module/Transmission Control Module Incompatible High
- P0701 Transmission Control System Range/Performance High
- P0702 Transmission Control System Electrical High
- P0705 Transmission Range Sensor A Circuit (PRNDL Input) High
- P0706 Transmission Range Sensor A Circuit Range/Performance High
- P0715 Input/Turbine Shaft Speed Sensor A Circuit High
- P0717 Input/Turbine Shaft Speed Sensor A Circuit No Signal High
- P0718 Input/Turbine Shaft Speed Sensor A Circuit Intermittent High
- P0720 Output Shaft Speed Sensor Circuit High
- P0721 Output Shaft Speed Sensor Circuit Range/Performance High
- P0722 Output Shaft Speed Sensor Circuit No Signal High
- P0723 Output Shaft Speed Sensor Circuit Intermittent High
- P0725 Engine Speed Input Circuit High
- P0726 Engine Speed Input Circuit Range/Performance High
- P0727 Engine Speed Input Circuit No Signal High
- P0728 Engine Speed Input Circuit Intermittent High
- P0747 Pressure Control Solenoid A Stuck On High
- P0748 Pressure Control Solenoid A Electrical High
- P0750 Shift Solenoid A High
- P0753 Shift Solenoid A Electrical High
- P0754 Shift Solenoid A Intermittent High
- P0755 Shift Solenoid B High
- P0758 Shift Solenoid B Electrical High
- P0759 Shift Solenoid B Intermittent High
Other components in Transmission
- Valve Body 334
- Transmission Fluid 308
- Pressure Control Solenoid 181
- Shift Solenoid 167
- Clutch Pack 122
- Clutch Actuator 89
- Shift Fork 72
- Gear Shift Actuator 72
- Transmission Fluid Pressure Sensor 70
- Electric/Auxiliary Transmission Fluid Pump 67
- Gear Lever Position Sensor 65
- Transmission Range Sensor 58
- Gear Shift Module 58
- Power Take-Off Unit 42
- Park/Neutral Switch 40
- Transmission Fluid Temperature Sensor 33
- Clutch Position Sensor 29
- Torque Converter 28
- Transmission Mode Switch 24
- Engine Disconnect Clutch 22
- Transmission Fluid Pump 22
- Transmission Fluid Filter 19
- Torque Converter Clutch Solenoid 17
- Output Speed Sensor 16
- Clutch 15
- Four Wheel Drive Switch 14
- Hydraulic Power Unit 14
- Four-Wheel Drive Clutch Control Module 14
- Manual Shift Switch 13
- Gate Select Actuator 13
- Transfer Case 11
- Intermediate Shaft Speed Sensor 10
- Shift Lock Solenoid 10
- Transfer Case Control Module 10
- Hydraulic Pressure Sensor 8
- Turbine Speed Sensor 7
- Skip Shift Solenoid 5
- Hydraulic Oil Temperature Sensor 5
- Transmission Fluid Cooler 4
- Reverse Inhibit Solenoid 4
- Driveline Disconnect Switch 4
- Reverse Light Switch 2
- Synchroniser 2
Information, not instruction
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Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.
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