Shift Light: Testing and Inspection

System Inspection





NOTE: Shift-up indicator light and duty output (terminal) are controlled by ECM through the same ECM terminal. If shift-up indicator light becomes bright and dim repeatedly, check the diag. switch circuit and1or test switch circuit for grounding to the body.

WARNING: This check requires test drive. Use special care for safety when driving.

- Turn ignition switch ON, and shift-up indicator light should light. If not, cause may be burned bulb, open wire, poor connection or faulty ECM. Proceed to "Shift-up indicator light and its circuit inspection".
- Start engine, and shift-up indicator light should go oft. If not, cause may be shorted wire to ground or faulty ECM.
- Warm up engine to normal operating temperature.
- With gear shift lever in low gear position, increase engine speed. When it exceeds 1,600 r/min., shift-up indicator light should light for 5 seconds at the longest. If it doesn't light, check VSS, ECT sensor and MAP sensor. If they are all in good condition, substitute a known-good ECM for existing one.

Shift-up Indicator Light and Its Circuit Inspection

- With ignition switch OFF, disconnect ECM coupler from ECM.
- Turn ignition switch ON, and shift-up indicator light should not light. If it lights, wire is shorted to ground.





- Ground terminal C21-18 of disconnected ECM coupler by using service wire. And then shift-up indicator light should light. If not, cause may be burned bulb, open wire or poor connection. Repair or replace as necessary.
- Connect coupler to ECM securely.