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 all connectors (and connections) for looseness, bending, corrosion, contamination, deterioration and/or damage.
3. Has a problem been found ?
YES
Repair as necessary and then go to "Verification of Vehicle Repair" procedure.
NO
Check DTC on engine, A/T and other systems which use VSS.
1) If DTC is detected DTC only in EPS, go to "Signal Circuit Inspection" procedure.
2) If DTC is detected DTC in other systems also, remove speedometer driven gear and check damage of gear.
-> If Speedometer driven gear is damaged, change it and then go to "Verification of Vehicle Repair" procedure.
-> If Speedometer driven gear is normal, go to "Power Supply Circuit Inspection" procedure.

Power Supply Circuit Inspection

1. Ignition "OFF".
2. Disconnect vehicle speed sensor connector.
3. Engine "ON".
4. Measure voltage between terminal "1"of vehicle speed sensor harness connector and chassis ground.
A. Specification : Approx. B+




5. Is the measured voltage within specifications ?
YES
1) Go to "Ground Circuit Inspection" procedure.
NO
1) Check for open/short to ground in power harness.
Repair as necessary and then go to "Verification of Vehicle Repair" procedure.

Ground Circuit inspection

1. Ignition "OFF".
2. Disconnect vehicle speed sensor connector.
3. Measure resistance between terminal "2"of Vehicle speed sensor harness connector and chassis ground.
A. Specification : Approx. 0 Ohm




4. Is the measured resistance within specifications ?
YES
1) Go to "Signal Circuit Inspection" procedure.
NO
1) Check for open/short to power in ground harness.
Repair as necessary and then go to "Verification of Vehicle Repair" procedure.

Signal Circuit Inspection

1. Ignition "OFF".
2. Connect Scantool to Data Link Connector (DLC).
3. Start engine and select "SCOPEMETER FUNCTION" on scantool.
4. Drive the vehicle and measure output signal between terminal "3"of EPS CM harness connector and chassis ground.
A. Specification :








5. Is vehicle speed sensor output signal within specifications ?
YES
1) Substitute with a known-good EPS CM and check for proper operation.
If the problem is corrected, replace EPS CM and then go to "Verification of Vehicle Repair" procedure.
NO
1) Check for open/short to ground in signal circuit and other systems which use VSS.
Repair as necessary and then go to "Verification of Vehicle Repair" procedure.
If a problem hasn't found, go to "Component Inspection" procedure.