Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
System Overview: Components
The following components are included in the automatic transmission control system:
- Transmission Control Module - Controls activation/deactivation of the solenoids by means of processing the input signals from the transmission speed and temperature sensors. Also stores adaptive data and diagnostic trouble codes and frozen values for diagnostics.
- Gear position indicator, integrated with Transmission Control Module - Provides Transmission Control Module information on selected gear position.
- Solenoid - Controls engine braking on 1st gear.
- Solenoid - Controls engine braking on 1st gear.
- Lock-up solenoid - Controls the lock-up function and also used with certain shiftings.
- Linear pressure solenoid - Controls transmission system pressure.
- Linear pressure solenoid - Controls transmission shift pressure and also used with certain shiftings.
- Linear pressure solenoid - Controls transmission shift pressure and also used with certain shiftings.
- Linear pressure solenoid - Controls transmission shift pressure and also used with certain shiftings.
- Linear pressure solenoid - Controls transmission shift pressure and also used with certain shiftings.
- Speed sensor, input shaft (1) - Provides Transmission Control Module (TCM) information on input shaft speed from the engine.
- Speed sensor, output shaft (2) - Provides Transmission Control Module (TCM) information on output shaft speed from the transmission.
- Oil temperature sensor (3) - Provides Transmission Control Module (TCM) information on transmission oil temperature.
- Gear Selector Module (GSM) - Provides Transmission Control Module (TCM) information on Geartronic position and winter mode (W) etc.
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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