Shift Light: Testing and Inspection

Diagnostic Chart:

Upshift Indicator Circuit:

CIRCUIT DESCRIPTION:
The upshift indicator indicates the best transaxle shift point for maximum fuel economy. The indicator is controlled by the Engine Control Module ECM and is turned "ON" by grounding the LT BLU wire from the I/P cluster assembly to the ECM. If the LT BLU wire is grounded the lamp will be "ON" all the time. If the circuit is open, the indicator will not light when commanded by the ECM.

TEST DESCRIPTION: Numbers below refer to circled numbers on the diagnostic chart.

1. This checks the upshift indicator's operation with the ignition switch in the "ON" position.

2. This checks for a poor connection or for a faulty ECM.

3. This determines if there is a problem in the upshift indicator's circuit.

4. This checks for an open LT BLU wire or for an open in the indicator bulb.