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TCM Power Supply and Ground Circuit Check




TCM Power Supply and Ground Circuit Check

Wiring Diagram










Troubleshooting

1. Back up power supply circuit check

Turn off ignition switch and disconnect connectors from TCM.
Check for proper terminal connection to TCM connectors.
If connections are OK, check that voltage between back up power supply circuit (A1) and vehicle body ground is battery voltage.

Is it in good condition?
YES -
Go to Step 2.
NO -
Repair or replace defective wire harness.

2. CVT relay power supply circuit (switch side) check

Remove CVT relay.
Check for proper terminal connection for CVT relay connector.
If connections are OK, check that voltage between CVT relay power supply circuit (switch side) (B1) and vehicle body ground is battery voltage.

Is it in good condition?
YES -
Go to Step 3.
NO -
Repair or replace defective wire harness.

3. CVT relay power supply (coil side) circuit check

Turn ignition switch to ON position.
Check that voltage between CVT relay power supply circuit (coil side) (B2) and vehicle body ground is battery voltage.

Is it in good condition?
YES -
Go to Step 4.
NO -
Repair or replace defective wire harness.

4. CVT relay ground circuit check

Check that voltage between CVT relay power supply circuit (coil side) (B2) and ground circuit (B3) is battery voltage.

Is it in good condition?
YES -
Go to Step 5.
NO -
Repair or replace defective wire harness.

5. CVT relay check

Check CVT relay. Testing and Inspection

Is it in good condition?
YES -
Go to Step 6.
NO -
Replace CVT relay.

6. Main power supply circuit check

Turn off ignition switch and install CVT relay.
Turn ignition switch to ON position.
Check that voltage between main power supply circuit 1 (A2) or main power supply circuit 2 (A3) and vehicle body ground are battery voltage.

Are they in good condition?
YES -
Go to Step 7.
NO -
Repair or replace defective wire harness.

7. TCM ground circuit check

Turn off ignition switch.
Check that resistance between each TCM ground circuit 1 (C1) and ground circuit 2 (C2) and vehicle body ground are less than 1 ohms.

Are they in good condition?
YES -
TCM power and ground circuit is in good condition.
NO -
Repair or replace defective wire harness.