Transfer Case Control Module
Controls the gearbox that splits drive between front and rear axles on a selectable four-wheel-drive vehicle, and reports which mode is engaged — two-wheel drive, four-wheel high, four-wheel low, or in transition.
That mode value has an outsized effect on the rest of the vehicle, and stability control is why. A vehicle in low range has enormously different wheel speeds and torque for a given pedal position, and a stability system acting on the wrong assumption about the driveline would intervene wrongly — so other modules refuse to act on a mode report they cannot believe.
The state worth recognising is in transition. A transfer case caught between modes — a shift motor that stalled, or a shift attempted while moving when it should not have been — reports a position that is genuinely neither, and drive may be partially or completely disconnected. So the first question on any transfer case fault is whether drive is actually reaching the wheels.
The module reports where the mechanism says it is, so the mode switch, the encoder or position sensor on the shift motor, and their wiring outrank the module itself as causes. All of it lives under the vehicle in the road spray and salt.
Also known as: transfer case module, tccm, 4wd control module, transfer box control module, transfer case controller
Referenced by 10 codes
Codes involving this component (10)
- P279A Transfer Case Gear High Incorrect Ratio Stop driving High
- P279B Transfer Case Gear Low Incorrect Ratio Stop driving High
- P279C Transfer Case Gear Neutral Incorrect Ratio Stop driving High
- C0071 2/4 Wheel Drive Status Input Moderate
- U0135 Lost Communication With Differential Control Module — Front Moderate
- U0138 Lost Communication With All Terrain Control Module Moderate
- U0303 Software Incompatibility With Transfer Case Control Module Moderate
- U0314 Software Incompatibility With Four-Wheel Drive Clutch Control Module Moderate
- U0403 Invalid Data Received From Transfer Case Control Module Moderate
- U0439 Invalid Data Received From All Terrain Control Module Moderate
Other components in Transmission
- Transmission Control Module 485
- 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
- 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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