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?

	▶ Repair as necessary and go to "Verification of vehicle Repair" procedure.
	▶ Go to "Signal Circuit Inspection" procedure.

IG KEY "OFF".

Disconnect ECM connector.

Disconnect ABS/ESP control unit connector.

Measure resistance between speed signal terminal of ECM harness connector and chassis ground.

Is the measured resistance within specification ?

	▶ Go to "Check open in harness" as follows.
	▶ Repair short to ground in harness, and go to "Verification of Vehicle Repair" procedure.

IG KEY "OFF".

Disconnect ECM connector.

Disconnect ABS/ESP control unit connector.

Measure resistance between speed signal terminal of ECM harness connector and speed signal signal of ABS(ESP) control module harness connector.

Is the measured resistance within specification ?

	▶ Substitute with a known - good ABS(ESP)Control Module and check for proper operation. If the problem is corrected, replace ABS(ESP)Control Module and go to "Verification of Vehicle Repair"
	▶ Repair Open circuit and then, go to "Verification of Vehicle Repair" procedure.