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.
Gear Selector Module (GSM)
The gear selector assembly is in the tunnel console. It is mechanically connected to the gearbox by a cable which moves the gear valve in the gearbox control system. The gear selector module (GSM) is positioned on the top panel of the gear selector assembly. The gear selector module (GSM) uses serial communication to communicate with the transmission control module (TCM) to light the gear position indicator. The indication occurs via LEDs in the top panel.
The gear selector control module (GSM) communicates with the central electronic module (CEM) to activate the shift-lock. The shift-lock solenoid power supply and ground is directly connected to the gear selector module (GSM).
The "W" switch in the gear selector assembly top panel is positioned on the printed circuit board for the gear selector module (GSM) and activates Winter mode.
There are diagnostics for the gear selector module (GSM). Diagnostic trouble codes (DTCs) are stored in the transmission control module (TCM) in the event of a fault.
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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.