2.
After approx. 10 seconds later disconnect the main relay.
First of all check damage of harness and terminals : Check terminals for contact resistance, corrosion and deformation.
When main relay is not operated although IG KEY "ON" signal at ECM connector (C101-K) terminal "28" is normal. If engine malfunction lamp does not "ON" and battery power at ECM, sensor and actuator is not supplied, Inspect the main relay circuit.
When IG KEY "ON" signal is input to ECM, ECM operates the main relay simultaneously. When IG KEY "OFF" signal is input to ECM, ECM stops the engine by stopping injector control and main relay control (System "OFF") after few seconds.
IG KEY "OFF", ENGINE "OFF"
After approx. 10 seconds later disconnect the main relay.
Measure the voltage of terminals of the main relay.
If battery power is not supplied at main relay terminal "30" and "85".
- Repair "ECU main fusible link (40A)" blown on the U/H junction box.
- Repair short to ground in power circuit on the U/H junction box.
IG KEY "OFF", ENGINE "OFF".
Disconnect ECM connector.
Measure the voltage of ECM connector (C230-K) terminal "72" after connecting or disconnecting the main relay.
"ECM Connector Inspection" of "Details Inspection(Equipment Setting)" reference
Specification :
- Connecting a main relay : 11.5 V~13.0 V
- Disconnecting a main relay : Below 0.2V
Case 1 : In case that If battery power is not supplied always after connecting or disconnecting the main relay.
Repair open in main relay control circuit between U/H junction box connector (U/H-C) terminal "32" and ECM connector (C230-K) terminal "72".
In case that If the main relay is operated after connecting a main relay.
- Repair short to ground in main relay control circuit between U/H junction box connector (U/H-C) terminal "32" and ECM connector (C230-K) terminal "72". (In case of short to ground in main relay control circuit, Engine does not stop after IG KEY "OFF" because the main relay is operated always.)
Case 2 : In case that If battery power is supplied always after connecting or disconnecting the main relay.
Repair short to battery in main relay control circuit between U/H junction box connector (U/H-C) terminal "32" and ECM connector (C230-K) terminal "72". (In case of short to battery in main relay control circuit, ECU would be damaged by high current when the main relay is operated by ECM)
Connect ECM connector (C230-K) terminal "72" to the chassis ground directly using jump wire when the main relay is connected.
When terminal "72" is connected to ground directly, the main relay is operated.
If the Main relay is not operated, Go to "Main relay inspection" procedure.
Check the voltage of the ECM connector (C230-K) terminal "1", "3", "5", When terminal "72" is connected to the chassis ground directly (Main relay is operated).
Specification :
- When terminal "72" is connected to the battery (-) directly (Main relay is operated) : 11.5 V~13.0 V
- When terminal "72" is not connected to the battery (-) directly (Main relay is not operated) : Below 0.2 V
Case 1 : In case that If battery power is not supplied always when a main relay is operated or is not operated.
Go to "Main relay inspection" procedure and repair open in power supply circuit between the main relay and the ECM.
Case 2 : In case that If battery power is not supplied at one or two terminal of the three terminals.
Repair open in power circuit when battery power is not supplied at one or two terminal of the three terminals.
Battery power is not supplied at terminal "1",
- Sensor #3 fuse (15A) is open or open circuit between U/H junction box connector (U/H-C) terminal "1" and ECM connector (C230-K) terminal "1".
Battery power is not supplied at terminal "3",
- IG coil fuse (20A) is open or open circuit between U/H junction box connector (U/H-C) terminal "36" and ECM connector (C230-K) terminal "3".
Battery power is not supplied at terminal "5",
- IG coil fuse (20A) is open or open circuit between U/H junction box connector (U/H-C) terminal "7" and ECM connector (C230-K) terminal "5".
Case 3 : In case that If battery power is supplied always when a main relay is operated and is not operated.
Repair short to battery in power circuit, because all power circuits (all sensor, actuator and module power circuits supplied battery power by main relay) are short to battery.(Engine would be not stopped after IG KEY "OFF" because battery power is supplied always by short to battery circuit (according to fuse capacity in short to battery circuit).
Case 4 : All main relay circuits are normal.
Go to "ECM ground inspection" procedure.
