11000334

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 then go to "Verification of Vehicle Repair" procedure.
	▶ Go to next step.

Measure resistance between CAN LOW terminal and CAN HIGH terminal of the HECU harness connector. <Measurement "A">

Measure resistance between CAN LOW terminal and CAN HIGH terminal of the HECU harness connector. <Measurement "B">

Specification :

Instrument cluster connected : Approx. 60 ± 3Ω <Measurement "A">

Instrument cluster disconnected : Approx. 120 ± 3Ω <Measurement "B">

Is the measured value within specifications?

▶ Go to next procedure.

▶ In case of the resistance "approx. 1Ω" in both measurement : Repair mutual short in C-CAN signal circuit of the HECU, and then go to "Verification of Vehicle Repair" procedure.

▶ In case of the resistance "approx. 120Ω" in both measurement : Go to "Component Inspection" procedure.

▶ In case of the resistance "∞ Ω" in both measurement : There is open circuit between HECU connector and other ECUs, go to "open circuit check" procedure.

Measure waveform between CAN HIGH and LOW terminals of the HECU and chassis ground.

Specification : HIGH terminal is normally 3.5V while LOW is 1.5V, the gap is approx. 2V

10.

Is the measured value over 4V?

	▶ There is short circuit to power in harness measured over 4V, repair short to power, and then go to "Verification of Vehicle Repair" procedure.
	▶ Go to next procedure.

11.

Is the measured value below 1V?

	▶ There is short circuit to ground in harness measured below 1V, repair short to ground and then go to "Verification of vehicle Repair" procedure.
	▶ Go to next procedure.