W/Harness Inspection

Terminal and 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 "Power Circuit Inspection" procedure

Power Supply Circuit Inspection

1. Check voltage
(1) IG "OFF".
(2) Disconnect the Cooling fan relay (high).
(3) IG "ON" and ENG "OFF"
(4) Measure the voltage between terminal 1, 4 of the Cooling fan relay (high) harness connector and chassis ground.
A. Specification : B+




(5) Is the measured voltage within specification?
YES
- Go to "Control Circuit Inspection" procedure.
NO
- Check if cooling fan fuse is open or not installed.
- Repair or replace as necessary and then, go to "Verification of Vehicle Repair" procedure.

Control Circuit Inspection

1. IG "OFF"
2. Disconnect the cooling fan relay (high).
3. IG "ON" & ENG "OFF"
4. Measure voltage between terminal 2 of the Cooling fan relay (high) harness connector and chassis ground.
A. Specification : Approx. 2.5V




5. Is the measured voltage within specification?
YES
- Substitute with a known-good ECM and check for proper operation.
If the problem is corrected, replace ECM and go to "Verification of Vehicle Repair" procedure.

CAUTION:
There is a memory reset function on scantool that can erase optional parts automatically detected and memorized by ECM. Before or after testing ECM on the vehicle, use this function to reuse the ECM on the others.

NO
- Repair open or short in control circuit and go to "Verification of Vehicle Repair" procedure.