Chart C-12A Coolant Fan Check (Single Speed Coolant Fan)

Fig. 001 - Chart C-12A Coolant Fan Check - Single Speed Coolant Fan.(1 of 3):

Fig. 002 - WIRING DIAGRAM for Chart C-12A Coolant Fan Check - Single Speed Coolant Fan. VIN 3:

CHART C-12A

COOLANT FAN CHECK (SINGLE SPEED FAN)

3.8L "A" SERIES

FUEL INJECTION (PORT)

1. Checks to see if fan runs at all times with ignition on.
2. Grounding the test terminal in the ALCL connector should cause the ECM to ground CKT 335. At this point the fan should run.
3. Grounding the coolant temp. override switch harness to ground should cause the relay to turn; on the fan. If the fan runs, the fan control relay and CKT 335 to the coolant temp. override switch are good.
4. Checks to see if coolant temp. override switch operates correctly. Test light should come on at about 108°C (226°F) and the "Hot light" on the instrument panel should come on above 116°C (241°F).
5. Checks to see if coolant fan delay relay works. With coolant temp override switch harness grounded and ignition "off", fan should run about 10 minutes or until ground jumper is removed.

Fig. 002 - WIRING DIAGRAM for Chart C-12A Coolant Fan Check - Single Speed Coolant Fan. VIN 3:

Fig. 003 - Chart C-12B Coolant Fan Check - Single Speed Coolant Fan. (2 of 3):

CHART C-12B

COOLANT FAN CHECK

3.8L "A" SERIES (SINGLE SPEED)

FUEL INJECTION (PORT)

1. This check bypasses the relay and applies bat + direct to the fan through CKT 532. At this point the fan should run.
2. Checks to see if problem is the control relay, wiring or ECM.
3. Checks for presence of ignition voltage to relay black connector terminal A.
4. Checks for presence of bat. + to relay gray connector terminal B.

Fig. 002 - WIRING DIAGRAM for Chart C-12A Coolant Fan Check - Single Speed Coolant Fan. VIN 3:

Fig. 005 - Chart C-12C Coolant Fan Check - Single Speed Coolant Fan. (3 of 3):

CHART C-12C

COOLANT FAN DELAY RELAY CHECK

3.8L "A" SERIES (SINGLE SPEED)

FUEL INJECTION (PORT)

1. With temp override switch harness grounded and the ignition "off, the delay relay should ground CKT 532 and cause the fan to run.
2. Checks to be sure constant bat. + is at CKT's 2N and 2P to the timer relay.
3. Checks to be sure CKT 639 does not have ignition voltage when the ignition switch is "off". If CKT 639 has battery voltage with the ignition off, the delay relay will not turn the fan on.
4. Checks to be sure CKT 450 is a good ground.