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Home >> Ford >> 2003 >> Thunderbird V8-3.9L VIN A >> Repair and Diagnosis >> Cruise Control >> Testing and Inspection >> Pinpoint Tests >> Test B
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Test B

PINPOINT TEST B: THE SPEED CONTROL SWITCH IS INOPERATIVE


Test B1-B3:






Test B4-B6:






Test B6-B9:






Normal Operation
The powertrain control module (PCM) sends a signal through circuit 7-PG24 (YE/BU) to the speed control switches which passes through the clockspring. The return signal is sent through circuit 31S-PG24 (BK/OG) and the clockspring.

Possible Causes
- circuit 7-PG24 (YE/BU) open, shorted to power or shorted to ground
- circuit 31S-PG24 (BK/OG) open, shorted to power or shorted to ground
- clockspring
- PCM
- speed control switch

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