W/Harness Inspection

Terminal and Connector Inspection

1. Many malfunctions in the electrical system are caused by poor harness and terminal condition. 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 "Signal Circuit Inspection" procedure.

Signal Circuit Inspection

1. Check short to battery in harness
(1) IG "OFF" and disconnect knock sensor connector.
(2) IG "ON" and ENG "OFF"
(3) Measure voltage between terminal 1 of knock sensor harness connector and chassis ground.
(4) Measure voltage between terminal 2 of knock sensor harness connector and chassis ground.
A. Specification : Approx. 1.5V








(5) Is the measured voltage within specification?
YES
- Go to "Check short to ground in harness" as follows.
NO
- Repair short to battery in harness, and go to "Verification of Vehicle Repair" procedure.
2. Check short to ground in harness
(1) IG "OFF" and disconnect knock sensor connector and PCM connector.
(2) Measure resistance between terminal 1 of knock sensor harness connector and chassis ground.
(3) Measure resistance between terminal 2 of knock sensor harness connector and chassis ground.
(4) Measure resistance between terminal 1 and 3 of knock sensor harness connector.
(5) Measure resistance between terminal 2 and 3 of knock sensor harness connector.
A. Specification : Infinite Ohms








(6) Is the measured resistance within specification ?
YES
- If the problem is corrected after substituting with a known - good knock sensor, replace it. If the problem is pending, check for proper operating after substituting with a known - good PCM. and then if the problem is corrected, replace PCM and go to "Verification of Vehicle Repair" procedure.
NO
- Repair open in harness, and go to "Verification of Vehicle Repair" procedure.

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