saturn Workshop Repair Guides

Saturn Workshop Service and Repair Manuals

"Check Engine" or "Service Engine Soon" Lamp (CEL)|Page 6424 > < Air Bag(s) Arming and Disarming|Service and Repair
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Malfunction Indicator Lamp: Description and Operation
"Check Engine" or "Service Engine Soon" Lamp (CEL)

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.

"Check Engine" or "Service Engine Soon" Lamp (CEL)|Page 6424 > < Air Bag(s) Arming and Disarming|Service and Repair