Coolant Circulation Pump Circuit
WHEN MONITORED
With the ignition on.
SET CONDITION
The A/C Heater Control Module detects an abnormal condition on the Coolant Circulation Pump Control circuit.
POSSIBLE CAUSES
- Fused B(+) circuit open
- Coolant circulation pump control circuit open
- Coolant circulation pump
- A/C heater control module
Diagnostic Test
1. MEASURE COOLANT CIRCULATION PUMP VOLTAGE
NOTE: Inspect Fuse 15 located in the Underhood Accessory Fuse Block. If the fuse is open, repair the cause of the open fuse before continuing.
Turn the ignition off.
Disconnect the Coolant Circulation Pump harness connector.
NOTE: Check connector - Clean/repair as necessary.
Measure the voltage of the Fused B(+) circuit at the Coolant Circulation Pump harness connector.
Q: Is the voltage above 10 volts?
YES: Go to 2
NO: Repair the Coolant Circulation Pump Fused B(+) circuit. Perform BODY VERIFICATION TEST. Body Verification Test
2. MEASURE THE VOLTAGE OF THE COOLANT CIRCULATION PUMP CONTROL CIRCUIT
With the ignition off.
Disconnect the A/C Heater Control Module harness connector.
NOTE: Check connector - Clean/repair as necessary.
Connect a jumper wire between the terminals in the Coolant Circulation Pump harness connector.
Measure the voltage of the Coolant Circulation Pump Control circuit at the
A/C Heater Control Module harness connector.
Q: Is the voltage above 10 volts?
YES: Go to 3
NO: Repair the Coolant Circulation Pump Control circuit for an open. Perform BODY VERIFICATION TEST. Body Verification Test
3. MEASURE THE VOLTAGE OF THE COOLANT CIRCULATION PUMP CONTROL CIRCUIT
With the ignition off.
Reconnect the Coolant Circulation Pump harness connector.
Measure the voltage of the Coolant Circulation Pump Control circuit at the
A/C Heater Control Module harness connector.
Q: Is the voltage above 10 volts?
YES: Replace the A/C Heater Control Module. Perform BODY VERIFICATION TEST. Body Verification Test
NO: Replace the Coolant Circulation Pump. Perform BODY VERIFICATION TEST. Body Verification Test