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Test M: The Power Lumbar Is Inoperative - Driver

PINPOINT TEST M: THE POWER LUMBAR IS INOPERATIVE - DRIVER

Normal Operation
The seat control switch is powered by battery voltage on circuit SBB15 (WH/RD) and is supplied ground on circuit GD126 (BK/WH). When the knob of the seat control switch is pressed, voltage and ground are supplied to the power lumbar motor. When pressing the lumbar knob in the opposite direction, the lumbar control switch reverses the polarity to the power lumbar motor, which moves the lumbar mechanism in the opposite direction.

This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Lumbar control switch
- Lumbar motor


M1:






M2-M4:






M4-M5: