Test A: The Speed Control Is Inoperative - No DTCs

PINPOINT TEST A: THE SPEED CONTROL IS INOPERATIVE - NO DTCS

A1-A7:

A7-A10:

A10-A11:

Normal Operation
The PCM sends a signal through circuit 151 (LB/BK) to the speed control switches, which passes through the clockspring. The return signal receives ground through circuit 848 (DG/OG) and the clockspring. The stoplamp switch sends a voltage signal through circuit 511 (LG) to the PCM when the brake pedal is applied, and deactivates the speed control, if engaged.

Vehicles equipped with a manual transmission have an additional clutch pedal position (CPP) switch. The CPP switch, normally closed, supplies a ground signal to the PCM through circuit 306 (TN/LB). When the clutch pedal is applied, the CPP switch moves to the open position causing the PCM to lose the ground signal and deactivate the speed control.

The speed control deactivator switch interrupts the power signal to the PCM through circuit 307 (BK/YE) when the brake pedal is applied firmly and passes the stoplamp switch trip point. This is a redundant signal to the PCM.

This pinpoint test is intended to diagnose the following:
- PCM not configured for speed control
- Stoplamp concern
- Speed control switch
- Digital transmission range (TR) sensor
- CPP switch
- PCM