Many malfunctions in the electrical system are caused by poor harness(s) and terminals. Faults can also be caused by interference from other electrical systems, and mechanical or chemical damage.
Check the following conditions:
Check for damaged harness and terminals: contact resistance, oxidation, bent or broken terminals.
Check for poor connection between ECM and component: backed out terminal, improper mating, broken locks or poor terminal to wire connection
Use a suitable male pin to ensure that contact in sockets is good. The pin should remain in position when pulled gently.
Has a problem been found?
YES
Repair as necessary and go to "Verification of Vehicle Repair" procedure
NO
System OK. Go to "Verification of Vehicle Repair" procedure
Thoroughly check ECTS for loose, poor connection, bent, corrosion, contamination, deterioration,or damage.
Is ETCS OK?
YES
Go to "Circuit inspection"
NO
Clean or Repair as necessary and go to "Verification of Vehicle Repair"
The inspection of ECTS signal line is for finding whether there is a open or short circuit in harness.
Turn ignition switch to OFF and disconnect ECTS connector.
Turn ignition switch to ON
Measure voltage of ECTS signal circuit.
Probe(+) : ECTS harness connector NO4.
Probe(-) : Chassis ground.
Specification: Approximately 5V
Is volage within Specification?
YES
Go to "Ground Circuit Inspection for ECTS"
NO
In case over 5V : Short circuit to battery between ECTS harness connector and ECM harness connector
In case 0V: Open circuit between ECTS harness connector and ECM harness connector
Repair as necessary and go to "Verification of Vehicle Repair" procedure
1.In case,when ECTS connector is disconnected,the voltage at terminal 4 is 0V.
▶Possible cause : Open or short between Terminal 4 of ETCS connector and terminal 39 of ECM.
Turn ignition switch to OFF and disconnect ECTS harness connector.
Measure resistance of ETCS ground circuit between ETCS harness connector and chassis ground.
Probe(+) : ETCS harness connector NO3.
Probe(-) : chassis ground.
Specification: below 1Ω
Does each resistance or voltage indicate continuity circuit?
YES
Go to "Component Inspection"
NO
Open circuit between ECTS harness connector and ECM harness connector
Open circuit between ECM harness connector and chassis ground
Repair as necessary and go to "Verification of Vehicle Repair" procedure
In case,when measuring resistence of ground circuit,the resistence is over 1ohm.
▶Possible cause : Short circuit between ECM ground point and ECM terminal 35
