Transmission Mode Switch: Testing and Inspection

Transmission Control Switch (TCS)

Transmission Control Switch (TCS):

Description: The transmission control switch is momentary contact switch. When the switch is pressed, a signal is sent to the PCM to allow automatic shifts from first through fourth gears or first through third gears only. The PCM then energizes the transmission control indicator lamp (TCIL).

Note: TCIL will also flash if the EPC circuit is shorted.

Sensor: Transmission Control Switch (TCS)

Transmission Function: Disable fourth gear operation.

Symptoms: No overdrive cancel when switch is cycled.

DTC: 632 tested during Key On Engine Off (KOEO) Self-Test. Refer to Manufacturer Code Charts

Actuator: Transmission Control Indicator Lamp (TCIL)

Transmission Function: Indicates overdrive cancel mode activated (lamp on) and EPC circuit shorted (lamp flashing).

Symptoms: Failed On- Overdrive cancel mode always indicated, no flashing for EPC circuit shorted. Failed Off- Overdrive cancel mode never indicated, no flashing for EPC circuit shorted.

DTC: 631. Refer to Manufacturer Code Charts