P1597 Speed Control Switch Always Low

SYMPTOM
P-1597 SPEED CTRL SW ALWAYS LOW

WHEN MONITORED
With the ignition key on, and battery voltage greater than 10.4 volts.

SET CONDITION
When switch voltage is less than 4.5 volts for 2 minutes.

POSSIBLE CAUSES
- S/C switch signal circuit shorted to ground
- S/C signal circuit shorted to sensor ground
- PCM defective
- S/C switch defective