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.
Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage.
Has a problem been found?
YES
▶ Repair as necessary and go to "Verification of Vehicle Repair" procedure
NO
▶ Go to " Signal Circuit Inspection " procedure.
This procedure is applied to vehicle with ABS (or ESP). In case of no ABS(or ESP), refer to "C1203 Wheel speed sensor front-RH open/short".
Check short to ground in harness
IG "OFF"
Disconnect PCM connector and ABS or EPS control module connector.
Measure resistance between terminal 52 of PCM harness connector and chassis ground.
Specification : Infinite
Is the measured resistance within specifications?
YES
▶ Go to "Check open in harness" as follows.
NO
▶ Repair short to ground in harness, and go to "Verification of Vehicle Repair" procedure.
Check for open in harness
Ignition "OFF"
Disconnect PCM connector and ABS or ESP control module connector.
Measure resistance between terminal "52" of PCM harness connector and terminal "14(With ESP: terminal 40)" of ABS control module harness connector.
Specification : Approx. below 1Ω
This picture is only applied to vehicle with ABS
Is the measured resistance within specifications?
YES
▶ Go to " Check wheel speed sensor " procedure.
NO
▶ Check open in harenss.
▶ Repair or replace as necessary and then, go to " Verification of Vehicle Repair" procedure.
Check wheel speed sensor
IG "OFF"
Check open or short in wheel speed sensor (Refer to "C1203 Wheel speed sensor front-RH open/short")
Is the wheel speed sensor normal?
YES
▶ Substitute with a known - good PCM/ ABS or ESP control unit and check for proper operation. If the problem is corrected, replace PCM/ ABS or ESP control unit and go to "Verification of Vehicle Repair" procedure.
NO
▶ Repair or replace it as necessary.
▶ And then go to " Verification of Vehicle Repair" procedure.
There is a memory reset function on scantool that can erase optional parts automatically detected and memorized by PCM. After testing PCM on the vehicle, use this function to reuse the PCM on the others
