SL L4-1.9L SOHC VIN 9 (1991)
Malfunction Indicator Lamp: Description and Operation
PCM Wiring
PURPOSE
The service engine soon (SES) telltale is used by the PCM to signal the operator of the vehicle of a possible problem.
The SES light is also used to relay diagnostic information during the diagnostic circuit check.
CIRCUIT OPERATION
When the PCM requires the indicator lamp to be turned "ON", it will supply a ground signal for the lamp. If the microprocessor is disabled for any
reason, a ground for the check engine indicator lamp will be automatically provided.
