Chart C-8A Manual Transaxle Upshift Indicator Check

Diagnostic Chart:

Manual Transaxle 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 PPL/RED wire from the Instrument Panel (I/P) cluster assembly to the ECM.

If the PPL/RED 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.

CHART 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 PPL/RED and BLK/WHT wires or for an open in the indicator bulb.

DIAGNOSTIC AIDS
An intermittent malfunction may be caused by a poor connection, rubbed through wire insulation, or a wire broken inside the insulation. Inspect harness connectors for backed out terminals, improper mating, broken locks, improperly formed or damaged terminals and poor terminal-to-wire connections before component replacement.