W/Harness Inspection
Terminal and Connector Inspection
1. Many malfunctions in the electrical system are caused by poor harness(es) 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
1) Repair as necessary and go to "Verification of Vehicle Repair" procedure
NO
1) Go to "Power Supply Circuit Inspection" procedure
Power Supply Circuit Inspection
1. Ignition "OFF"
2. Disconnect MAF sensor connector
3. Ignition "ON" & Engine "OFF"
4. Measure voltage between terminal 2 of the sensor harness connector and chassis ground
A. Specification : Approx. B+
5. Is voltage within the specification?
YES
1) Go to "Signal Circuit Inspection" procedure.
NO
1) Check for an open or short to ground in the power supply circuit between the MAF sensor and fuel pump relay. Repair as necessary and go to "Verification of Vehicle Repair" procedure
Signal Circuit Inspection
Check for Open in Signal Harness
1. Ignition "OFF"
2. Disconnect ECM connector
3. Measure resistance between terminals 3 of sensor harness connector and 10 of the ECM harness connector
A. Specification : Approx. 0 Ohm
4. Is resistance within the specification?
YES
1) Go to next step as below
NO
1) Check for an open in signal harness. Repair as necessary and go to "Verification of Vehicle Repair" procedure
Check for Short to Ground in Signal Harness
1. Measure resistance between terminal 3 of sensor harness connector and chassis ground
A. Specification : Infinite
2. Is resistance within the specification?
YES
1) Go to "Component Inspection" procedure.
NO
1) Check for short to ground in signal harness. Repair as necessary and go to "Verification of Vehicle Repair" procedure