Electrical systems consist of a lot of harness and connectors, poor connection of terminals can cause various problems and damage of component.
Perform checking procedure as follows.
Check damage of harness and terminals : Check terminals for contact resistance, corrosion and deformation.
Check connecting condition of ECM and component connector : Check terminal separation, damage of locking device and connecting condition between terminal and wiring.
Disconnect the pin which requires checking at male connector and insert it to the terminal at female connector for checking connecting condition. (After checking, reconnect the pin at correct position.)
Is the problem found?
![]() | ▶ Repair the trouble causing part and go to "Verification of Vehicle Repair" procedure. |
![]() | ▶ Go to "Power Circuit Inspection". |
IG key OFF.
Disconnect 'ENGINE CONTROL RELAY'.
IG key ON.
Check voltage between 'ECU FUSIBLE LINK 30A' (85) terminal of 'ENGINE CONTROL RELAY' harness connector and chassis ground.
Check voltage between 'ECU FUSIBLE LINK 30A' (30) terminal of 'ENGINE CONTROL RELAY' harness connector and chassis ground.
Specification : 10.5V ~ 14.5V
Is the measured value within specification?
![]() | ▶ Go to "Check open in power circuit" as follows. |
![]() | ▶ If no voltage is detected, repair open / short to ground between 'ECU FUSIBLE LINK 30A' (85) / (30) terminal of 'ENGINE CONTROL RELAY' harness connector and 'ECU FUSIBLE LINK 30A' terminal of 'E/R JUNCTION BOX' harness connector, and go to "Verification of Vehicle Repair" procedure. ▶ If the voltage is high than specification value, repair short to battery between 'ECU FUSIBLE LINK 30A' (85) / (30) terminal of 'ENGINE CONTROL RELAY' harness connector and 'ECU FUSIBLE LINK 30A' terminal of 'E/R JUNCTION BOX' harness connector, and go to "Verification of Vehicle Repair" procedure. |
IG key OFF.
Disconnect 'ENGINE CONTROL RELAY' and ECM connector.
Jump 'ECU FUSIBLE LINK 30A' (30) terminal and 'Engine control relay 'ON' (87) terminal of 'ENGINE CONTROL RELAY' harness connector with jumper wire.
Check voltage between 'Engine control relay 'ON' terminal of ECM harness connector and chassis ground.
Specification : 10.5V ~ 14.5V
Is the measured value within specification?
![]() | ▶ Go to "Control Circuit Inspection". |
![]() | ▶ If no voltage is detected, repair open / short to ground between 'Engine control relay 'ON' (87) terminal of 'ENGINE CONTROL RELAY' harness connector and 'Engine control relay 'ON' terminal of ECM harness connector, and go to "Verification of Vehicle Repair" procedure. ▶ If the voltage is high than specification value, repair short to battery between 'Engine control relay 'ON' (87) terminal of 'ENGINE CONTROL RELAY' harness connector and 'Engine control relay 'ON' terminal of ECM harness connector, and go to "Verification of Vehicle Repair" procedure. |
IG key OFF.
Disconnect 'ENGINE CONTROL RELAY' connector and ECM connector.
Check resistance between 'Engine control relay control (86)' terminal of 'ENGINE CONTROL RELAY' harness connector and 'Engine control relay control (86)' terminal of ECM harness connector.
Specification : Continuity (Below 1.0Ω)
Is the measured value within specification?
![]() | ▶ Repair short to ground between 'Engine control relay control' (86) terminal of 'ENGINE CONTROL RELAY' harness connector and 'Engine control relay control' terminal of ECM harness connector, and go to "Verification of Vehicle Repair" procedure. |
![]() | ▶ Repair open between 'Engine control relay control' (86) terminal of 'ENGINE CONTROL RELAY' harness connector and 'Engine control relay control' terminal of ECM harness connector, and go to "Verification of Vehicle Repair" procedure. |
IG key OFF.
Disconnect 'ENGINE CONTROL RELAY' and ECM connector.
Check resistance between 'Engine control relay control' terminal of ECM harness connector and Chassis ground.
Specification : Infinite (∞ Ω)
IG key ON.
Check voltage between 'Engine control relay control' terminal of ECM harness connector and Chassis ground.
Specification : 0.0V ~ 0.1V
Is the measured value within specification?
![]() | ▶ Go to "Component Inspection" procedure. |
![]() | ▶ If abnormal resistance value is detected, repair short to ground between 'Engine control relay control' terminal of 'ENGINE CONTROL RELAY' harness connector and 'Engine control relay control' terminal of ECM harness connector. ▶ If abnormal voltage value is detected, repair short to battery between 'Engine control relay control' terminal of 'ENGINE CONTROL RELAY' harness connector and 'Engine control relay control' terminal of ECM harness connector. |