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For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 1998 🢒 Prizm 🢒 HVAC 🢒 HVAC Systems - Manual 🢒 Condenser Fan Inoperative - Auxiliary

Step

Action

Yes

No

The auxiliary fan motor is mounted on the right side of the radiator/condenser assembly. The fans run at low speed (series configuration) when the A/C is operating and the engine coolant temperature (ECT) is below 83°C (181°F). The fans run at high speed (parallel configuration) when the ECT is above 93°C (199°F).

A short to ground in the ground circuit of the A/C fan no. 1 and 2 relays will cause both fans to be inoperative once the ECT reaches 93°C (199°F). This table assumes that the main (left side) fan motor is functioning normally.

The following are symptoms and possible causes.

    • Both fans inoperative:
       - Open in the supply voltage circuit to the fan no. 1 and the engine main relays in fuse and relay block 1
       - High resistance or poor connection in fuse and relay block 1
       - Faulty engine main relay
       - Short to ground in the fan no. 1 or the fan no. 2 coil ground circuit
       - Engine coolant temperature (ECT) sensor or powertrain control module (PCM) malfunction
    • Main fan inoperative:
       - Faulty main fan motor
       - Faulty fan no. 1 relay
       - Open in main fan circuit
    • Auxiliary fan inoperative:
       - Faulty auxiliary fan motor
       - Faulty fan no. 2 relay
       - Open in auxiliary fan circuit
    • Both fans inoperative in low speed:
       - Faulty fan no. 2 relay
       - Faulty fan no. 3 relay
       - Open in series portion of fan circuit

1

Did you perform the HVAC System Check?

Go to Step  2

Go to HVAC System Check

2
  1. Run the engine until operating temperature is reached and the thermostat opens.
  2. Stop the engine.
  3. Disconnect the auxiliary fan motor connector.
  4. Connect a test lamp across the auxiliary fan motor connector.
  5. Start the engine.

Does the test lamp light?

Go to Step  3

Go to Step 4

3

Replace the auxiliary fan motor. Refer to Engine Cooling Fan Replacement in Engine Cooling.

Is the repair complete?

Go to HVAC System Check

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4

Test for battery voltage at the auxiliary fan motor connector terminal 2.

Is battery voltage present?

Go to Step 8

Go to Step 5

5

Inspect the CDS fuse in fuse and relay block 2 for an open.

Is the fuse open ?

Go to Step 6

Go to Step 7

6

Repair the short to ground in the BLU/RED wire between the CDS fuse and the auxiliary fan motor connector terminal 2. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

Go to HVAC System Check

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7

Repair the open in the BLU wire between the CDS fuse and fuse and relay block 1 OR in the BLU/RED wire between the CDS fuse and the auxiliary fan motor connector terminal 2. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

Go to HVAC System Check

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8
  1. Remove the A/C fan no. 2 relay from fuse and relay block 2.
  2. Test for an open between the auxiliary fan motor connector terminal 1 and the A/C fan no. 2 relay cavity 3.
  3. Test for an open between the A/C fan no. 2 relay cavity 4 and G104. Refer to

    Fuse and Relay Block 1
    Object Number: 380712 Size: MF
    (1)ST Relay
    (2)HEAD Relay
    (3)EFI or F-HTR Relay
    (4)Fuse Puller
    (5)ENGINE MAIN Relay
    (6)HORN Relay
    (7)AM1 Fuse 50A
    (8)RDI Fuse 30A
    (9)FAN Relay
    (10)ALT-S Fuse 7.5A
    (11)Empty
    (12)Not Used
    (13)HORN Fuse 20A
    (14)Not Used
    (15)Not Used
    (16)AM2 Fuse 30A
    (17)HAZARD Fuse 20A
    (18)DOME Fuse 20A
    (19)ALT Fuse 100A
    (20)ABS Fuse 50A
    (21)MAIN Fuse 50A
    (22)Not Used
    (23)Fuse and Relay Block 1
    in Wiring Systems.

Is an open present?

Go to Step 10

Go to Step 9

9

Replace the fan no. 2 relay. Refer to Condenser Fan Relay Replacement .

Is the repair complete?

Go to HVAC System Check

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10

Repair the open. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

Go to HVAC System Check

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