Corsica L4-121 2.0L (1988)
Fig. 021b Wiring Diagram Chart C-12C Engine Cooling Fan
CHART C-12C
ENGINE COOLING FAN
2.0L
FUEL INJECTION (TBI)
Circuit Description: Battery voltage to operate the cooling fan motor is supplied to relay terminal "E". Ignition voltage to energize the relay is
supplied to relay terminal "C". When the ECM grounds CKT 335, the relay is energized and the cooling fan is turned "ON". When the engine is
running, the ECM will turn the cooling fan "ON" if:
A/C is "ON.
Coolant temperature greater than 108 degrees C (230 degrees F).
Code 14 or 15, coolant sensor failure.
Diagnostic Aids:
If the owner complained of an overheating problem, it must be determined if the complaint was due to an actual boil over, or the hot light, or temp.
gauge indicated over heating.
If the gauge, or light, indicates overheating, but no boilover is detected, the gauge circuit should be checked. The gauge accuracy can, also, be
checked by comparing the coolant sensor reading using a "Scan" tool and comparing its reading with the gauge reading.
If the engine is actually overheating and the gauge indicates overheating, but the cooling fan is not coming on, the coolant sensor has probably shifted
out of calibration and should be replaced.
