Operation CHARM: Car repair manuals for everyone.

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

Check voltage
1. IG Key "OFF".
2. Disconnect the A/C pressure sensor connector
3. IG Key "ON".
4. Measure the voltage between power terminal of A/C pressure sensor harness connector and chassis ground.
A. Specification : Approx. 5V




5. Is the measured voltage within specification ?
YES
> Go to "Ground Circuit Inspection" procedure.
NO
> Repair open in harness and go to "Verification of Vehicle Repair" procedure.

Ground Circuit inspection

Check open in harness
1. IG Key "OFF".
2. Disconnect the A/C pressure sensor connector.
3. IG Key "ON".
4. Measure the voltage between power terminal of A/C pressure sensor harness connector and chassis ground. (Measurement "A")
5. Measure the voltage between power and ground terminals of A/C pressure sensor harness connector. (Measurement "B")
A. Specification : The Difference between "A" and "B" is below 200 mV.








6. Is the measured voltage within specification ?
YES
> Go to "Signal Circuit Inspection" procedure.
NO
> Repair as necessary and go to "Verification of Vehicle Repair" procedure.

Signal Circuit Inspection

Check voltage
1. IG Key "OFF".
2. Disconnect the A/C pressure sensor connector.
3. IG Key "ON".
4. Measure the voltage between signal terminal of A/C pressure sensor harness connector and chassis ground.
A. Specification : Approx. 0V




5. Is the measured voltage within specification ?
YES
1) Go to "Component Inspection" procedure.
NO
1) Go to "Check short to battery in harness" procedure.
Check short to battery in harness
1. IG Key "OFF".
2. Disconnect A/C pressure sensor connector and PCM connector.
3. Measure the resistance between signal and power terminals of A/C pressure sensor harness connector.
A. Specification : Infinite




4. Is the measured resistance within specification ?
YES
1) Go to "Component Inspection" procedure.
NO
1) Repair short in harness and go to "Verification of Vehicle Repair" procedure.