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
Turn ignition switch to OFF and disconnect TPS harness connector.
Turn ignition switch to ON
Measure the reference voltage of TPS circuit between TPS harness connector and ECM harness connector.
Probe(+) : TPS harness connector NO2.
Probe(-) : Chassis ground.
Specification: Approximately 5V
Is voltage within Specification?
YES
Go to "Inspection of sensor signal line"
NO
Short circuit to chassis ground between TPS harness connector and reference voltage
Open circuit between TPS harness connector and ECM connector
Repair as necessary and go to "Verification of Vehicle Repair"
1.In case,when the TPS connector is disconnected,the voltage of TPS terminal 2 is 0 V.
▶Possible cause: Open or short between terminal 32 of ECM and Terminal 2 of TPS
Turn ignition switch to OFF and disconnect TPS harness connector.
Turn ignition switch to ON
Measure voltage of TPS signal circuit between TPS harness connector and ECM harness connector.
Probe(+) : TPS harness connector NO1.
Probe(-) : Chassis ground.
Specification: Approximately 5V
Is voltage within Specification?
YES
Go to "Inspection of TPS ground line"
NO
Open circuit or short circuit to chassis ground between TPS harness connector and signal circuit
Open circuit between TPS harness connector and ECM harness connector
Repair as necessary and go to "Verification of Vehicle Repair"
1.In case,when the TPS connector is disconnected,the voltage of TPS terminal 1 is 0 V.
▶Possible cause: Open or short between terminal 16 of ECM and terminal 1 of TPS.
Turn ignition switch to OFF and disconnect TPS harness connector.
Turn ignition switch to ON
Measure voltage and resistance of TPS ground circuit between TPS harness connector and ECM harness connector.
Probe(+) : TPS harness connector NO3.
Probe(-) : Chassis ground
Specification: below 0.5V below 1Ω
Is voltage and resistance within Specification?
YES
Go to "Inspection of ECM"
NO
Open circuit between TPS harness connector and ECM harness connector
Repair as necessary and go to "Verification of Vehicle Repair"
1.In case,when TPS connector is disconnected,the resistance of TPS terminal 3 is infinite.
▶Possible cause : Short circuit between terminal 17 of ECM and terminal 3 of TPS.