P1597

Tests 1 - 3:

Tests 4 - 5:

SYMPTOM
P1597 - SPEED CONTROL SWITCH 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