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 ?
Signal Circuit Inspection
1. Check voltage
(1) IG "OFF" and disconnect IATS connector.
(2) IG "ON" and ENG "OFF"
(3) Measure voltage between terminal 4 of IATS harness connector and chassis ground.
Specification : Approx. 5V
(4) Is the measured voltage within specification ?
2. Check short to battery in harness
(1) IG "OFF" and disconnect IATS connector and PCM connector.
(2) Measure resistance between terminals 2 and 4 of IATS harness connector.
(3) Measure resistance between terminals 1 and 4 of IATS harness connector.
Specification : Infinite
(4) Is the measured resistance within specification ?
3. Check open in harness
(1) IG "OFF" and disconnect IATS connector and PCM connector.
(2) Measure resistance between terminal 4 of IATS harness connector and 44 of PCM harness connector.
Specification : below 1 ohms
(3) Is the measured resistance within specification ?
Ground Circuit inspection
1. IG "OFF" and disconnect IATS connector.
2. Measure voltage between terminal 4 of IATS harness connector and chassis ground.
3. Measure voltage between terminals 4 and 5 of IATS harness connector.
Specification : Voltage difference between measurement "A" and "B" is below 200 mV.
4. Is the measured voltage within specification ?