P0646

Test 1:

Tests 2 - 5:

Tests 6 - 10:

Tests 11 - 12:

SYMPTOM
P0646-A/C CLUTCH RELAY CONTROL CIRCUIT LOW

WHEN MONITORED
Ignition ON.

SET CONDITION
The PCM sense low voltage for more than 2.73 seconds.

POSSIBLE CAUSES
- Intermittent condition
- Ground circuit open
- A/C clutch
- Fused B+ circuit
- A/C clutch output CKT open
- A/C clutch output CKT short to ground
- Fused ignition switch circuit
- A/C clutch relay resistance
- A/C clutch relay control CKT open
- A/C clutch relay control CKT short to GD
- PCM