P1625
DTC P1625 COOLING FAN RELAY CIRCUIT MALFUNCTION HIGHComponent Location:
GENERAL DESCRIPTION
The Cooling fan motor is controlled by the PCM through the cooling fan relay The PCM monitors coolant temperatures through the Engine Coolant Temperature (ECT) sensor. By monitoring the ECT sensor the PCM can calculate when to turn the cooling fan motor ON and OFF.
DTC DESCRIPTION
If the signal above threshold value, the PCM judged this as a fault and DTC is set.
DTC Detecting Condition:
Specification:
Schematic Diagram:
MONITOR DTC STATUS
This is the inspection procedure to determine whether it is present DTC or memoried one by monitoring the current signal or by using the function of oscilloscope with Hi-scan pro.
1. Connect scantool to Data Link Connector(DLC).
2. Warm up the engine to normal operating temperature.
3. Monitor the "COOLING FAN" parameter on the scantool.
Service standard
4. Is parameter displayed within specifications?
YES: Fault is intermittent caused by poor contact in the sensor's and/or PCM's connector or was repaired and PCM memory was not cleared.Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage. Repair or replace as necessary and then go to "Verification of Vehicle Repair" procedure
NO: Go to "W/Harness Inspection" procedure
TERMINAL & CONNECTOR INSPECTION
1. Many malfunctions in the electrical system are caused by poor harness and terminals. Faults can also be caused by interference from other electrical systems, and mechanical or chemical damage.
2. Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage.
3. Has a problem been found?
YES: Repair as necessary and go to "Verification of vehicle Repair" procedure.
NO: Go to "Control circuit inspection" procedure.
CONTROL CIRCUIT INSPECTION
1. Check for short to ground in harness
1. Ignition "OFF"
2. Disconnect RAD FAN Relay.
3. Ignition "ON" & Engine "OFF"
4. Measure voltage between terminal 3 of RAD FAN Relay harness connector and chassis ground.
Specification : approximately 3.7 V
5. Is measure voltage within Specification?
YES: Go to "Component Inspection" procedure.
NO:
- Check for open or Short to ground in control circuit.
- Repair as necessary and then go to "Verification of Vehicle Repair" procedure.
NOTE: In case,when RAD FAN Relay connector is disconnected,the voltage at terminal 3 is 0 V.
- Possible cause : Short to ground in control circuit
COMPONENT INSPECTION
1. Check RAD FAN Relay
1. Ignition "OFF"
2. Disconnect RAD FAN Relay.
3. Measure resistance between terminal 3 and 5 of RAD FAN Relay connected (To sensor side)
Specification: approximately 70 - 120 Ohms
4. Is measure resistance within Specification?
YES: Substitute with a known-good PCM and check for proper operation. If the problem is corrected, replace PCM and then go to "Verification of Vehicle Repair" procedure.
NO: Substitute with a known-good RAD FAN Relay heater and check for proper operation. If the problem is corrected, replace RAD FAN Relay and then go to "Verification of Vehicle Repair" procedure.
VERIFICATION OF VEHICLE REPAIR
After a repair, it is essential to verify that the fault has been corrected.
1. Monitor and record the Freeze Frame Data for the Diagnostic Trouble Code (DTC) which has been diagnosed.
2. Using a Scantool, Clear the DTCs.
3. Operate the vehicle within conditions noted in the freeze frame data or enable conditions.
4. Monitor that all rediness test have been verified as "Complete"
5. Are any DTCs present?
YES: Go to the applicable troubleshooting procedure.
NO: System is performing to specification at this time.