Shift Light: Testing and Inspection

If Upshift indicator is not working properly, perform the following test.
1. Disconnect ECM connector C1.
2. Place ignition switch in run.
3. Measure voltage at terminal A2 of ECM connector.
4. If battery voltage is present, further ECM diagnosis is necessary.
5. If battery voltage is not present, repair open circuit in brown/black wire, circuit 456.