P1388

Tests 1 - 3:

Tests 4 - 8:

Test 9:

SYMPTOM
P1388 AUTO SHUTDOWN RELAY CONTROL CIRCUIT

WHEN MONITORED
With ignition key ON and battery voltage greater than 10.4 volts.

POSSIBLE CAUSES
- Fused ignition output circuit open
- Wiring and connectors observable defect
- Wiring harness intermittent defect
- Auto shutdown relay
- ASD relay control circuit shorted to ground
- Auto shutdown relay control circuit open
- Powertrain control module (ASD relay control circuit)