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.

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 next step as below.

Ignition "OFF".

Disconnect ISCA connector.

Ignition "ON" & Engine "OFF".

Measure voltage between terminal 2 of the ISCA harness connector and chassis ground.

Specification : Approx. B+

Is voltage within the specification?

YES

▶ Go to "Signal Circuit Inspection" procedure.

NO

▶ Check for an open or short to ground in the power supply circuit between the ISCA valve and fuel pump relay. Repair as necessary and go to "Verification of Vehicle Repair" procedure.

Ignition "ON" & Engine "OFF".

Measure voltage between terminal 1 of the ISCA harness connector and chassis ground.

Specification : Approx. 3~4V

Is voltage within the specification?

YES

▶ Thoroughly check connectors for loose or poor connections, bending, corrosion, contamination, deterioration, or damage. Repair or replace as necessary and go to "Verification of Vehicle Repair" procedure

NO

▶ Go to next step as below.

Check for short to power in signal harness

(4)

Measure voltage between terminal 1 of the ISCA harness connector and chassis ground

Specification : Approx. 0V