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TCM Power and Ground Circuit Check: Troubleshooting

TROUBLESHOOTING CHART

Step

Action

Yes

No

1

Check TCM power circuit

Disconnect TCM connector with ignition switch OFF.
Check for proper connection to TCM at "G08-20" terminal.
If OK, turn ignition switch ON and check voltage at terminal "G08-20" of disconnected TCM connector.

Is it 10 - 14 V?

Go to Step 2.

"BLK/WHT" circuit open.

2

Check TCM ground circuit

Turn ignition switch OFF.
With TCM connectors disconnected, check for proper connection to TCM at "G08-15" terminal.
If OK, check resistance between "G08-15" / "G08-19" terminal of disconnected TCM connector and body ground.

Is continuity indicated?

TCM power and ground circuits are in good condition.

"BLK" circuit open.