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

Step

Action

Yes

No

The main fan motor is mounted on the left side of the radiator/condenser assembly. 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 parallel portion of the circuit is functioning normally. Therefore, the malfunction is in the series portion of the circuit.

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. Exchange the A/C fan no. 3 relay with a known good relay (the A/C fan no. 1 relay, the A/C MG relay, or the horn relay).
  2. Start the engine. The engine must be below operating temperature.
  3. Move the blower speed selector switch to any position except OFF.
  4. Depress the A/C switch to the ON position.

Do the cooling fans run at low speed?

Go to Step  9

Go to Step  3

3
  1. Turn the ignition switch to the LOCK position.
  2. Remove the A/C fan no. 3 relay from fuse and relay block 2.
  3. Start the engine.
  4. Turn the blower speed selector switch to any position except OFF.
  5. Test for battery voltage at the A/C fan no. 3 relay cavity 1. Refer to

    Fuse and Relay Block 2
    Object Number: 334466 Size: SF
    (1)A/C MG Relay
    (2)A/C FAN No.3 Relay
    (3)A/C FAN No.3 Relay
    (4)Dimmer Relay
    (5)CDS Fuse 30A
    (6)HEAD (LH-LWR) Fuse 10A
    (7)HEAD (RH-LWR) Fuse 10A
    (8)DRL Fuse 7.5A
    (9)Fuse and Relay Block 2
    in Wiring Systems.

Is battery voltage present?

Go to Step  5

Go to Step  4

4

Repair the open in the BLK/WHT wire between the A/C fan no. 3 relay cavity 1 and the A/C MG relay cavity 3 in fuse and relay block 2. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

Go to HVAC System Check

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5

Test for an open in the WHT/BLK between the A/C fan no. 3 relay cavity 2 and G103.

Is an open present?

Go to Step  8

Go to Step  6

6

Test for an open in the WHT/RED wire between the A/C fan no. 3 relay cavity 3 and the A/C fan no. 2 relay cavity 5.

Is an open present?

Go to Step  8

Go to Step  7

7

Test for an open in the WHT wire between the A/C fan no. 3 relay cavity 5 and fuse and relay block 1.

Is an open present?

Go to Step  8

Go to Step  9

8

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

Is the repair complete?

Go to HVAC System Check

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9

Replace the A/C fan no. 3 relay. Refer to Condenser Fan Relay Replacement .

Is the repair complete?

Go to HVAC System Check

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