Diagnostic Procedure
NO.18 COOLING SYSTEM CONCERNS-RUNS COLD [BP, BP WITH TC] DIAGNOSTIC PROCEDURE
| STEP |
INSPECTION |
ACTION |
| 1 |
- Is customer complaint "Lack of passenger compartment heat" only?
|
Yes |
Inspect A/C and heater system. |
| No |
Go to the next step. |
| 2 |
- Does engine speed continue at fast idle?
|
Yes |
Go to symptom troubleshooting No.9 "NO.9 FAST IDLE/RUNS ON ". |
| No |
Go to the next step. |
| 3 |
|
Yes |
Inspect condenser fan and main fan operation.
- If both or either fan operate abnormally, inspect for following:
- Main cooling fan relay is stuck closed.
- Condenser fan relay is stuck closed.
- Short to ground between main cooling fan relay and PCM terminal 2B
- Short to ground between condenser fan relay and PCM terminal 2C
- Circuit between main cooling fan relay and fan motor shorts to battery supply line
- Circuit between condenser fan relay and fan motor shorts to battery supply line
|
| No |
Access ECT V PID on WDS or equivalent.
Inspect for both ECT and temperature gauge on instrument cluster readings.
- If temperature gauge on instrument cluster indicates normal range but ECT is not same as temperature gauge reading, inspect ECT sensor.
- If temperature gauge on instrument cluster indicates cold range but ECT is normal, inspect temperature gauge and heat gauge unit.
|
| 4 |
- Verify test results.
- If okay, return to diagnostic index to service any additional symptoms.
- If malfunction remains, inspect related Service Bulletins and/or On-line Repair Information and perform repair or diagnosis.
- If vehicle is repaired, troubleshooting completed.
- If vehicle is not repaired or additional diagnostic information is not available, replace PCM.
|