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Home >> Mercury >> 1989 >> Tracer L4-1589cc 1.6L SOHC >> Repair and Diagnosis >> Powertrain Management >> Computers and Control Systems >> Malfunction Indicator Lamp >> Description and Operation
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Malfunction Indicator Lamp: Description and Operation


The malfunction indicator lamp is used only on EFI models. This lamp indicates a malfunction in the Electronic Engine Control system. If a malfunction occurs, the lamp will illuminate. The malfunction detected may or may not be a noticeable driveability problem. The lamp will be automatically reset during diagnosis and repair of the system. This indicator system monitors the following:
1. Air Temperature sensor (ACT).
2. Barometric Pressure (BP) sensor.
3. Clutch switch, manual transaxle.
4. Engine coolant temperature (ECT) sensor.
5. Engine coolant temperature (ECT) switch.
6. Exhaust gas oxygen (EGO) sensor.
7. Ignition coil ( - ) terminal.


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