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Cooling Fan Inoperative (Inoperative in High and Low Speed)

WARNING: This page is about a different car, the 2004 Pontiac Vibe. However, it is still accessible from the selected car via links, so may be relevant.
Reference Table

Symptom Causes
Fan motor inoperative in both speeds
  • Open or short to ground in the fan 1 relay supply voltage circuits.
  • Open or short to B+ in the fan 1 relay coil control circuit.
  • Open or short to ground in the fan motor supply voltage circuit.
  • Short to ground in the fan 2 coil supply voltage circuit.
  • Open or short to B+ in the fan motor ground circuit.
  • Short to B+ in the fan 2 coil control circuit.
Fan motor inoperative in high speed only
  • Open in the fan 2 relay supply voltage circuit.
  • Open in the fan 2 relay coil control circuit.
  • Open in the fan 2 relay high speed ground circuit.
Fan motor low speed operates at high speed
  • Short to ground in the fan motor ground circuit.
  • Short to ground in the fan resistor circuit.
Fan motor inoperative in low speed only Open or short to B+ in the fan resistor circuit.
Cooling Fan Inoperative (Inoperative in High and Low Speed)

Step Action Yes No
Schematic Reference: Engine Cooling Schematics .
Connector End View Reference: Cooling System Connector End Views 
DEFINITION: The cooling fan motor is inoperative in both fan speeds.
1 Did you review the Cooling System Description and Operation  and perform the necessary inspections? Go to Step 2  Go to Symptoms - Engine Cooling 
2 Run the engine until operating temperature is reached and the thermostat opens.
Does the cooling fan operate?
Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems Go to Step 3 
3
  1. Stop the engine.
  2. Disconnect the fan motor connector.
  3. Connect a test lamp across the fan motor connector.
  4. Start the engine.
Does the test lamp illuminate?
Go to Step 11  Go to Step 4 
4
  1. Connect the fan motor.
  2. Exchange the fan 1 relay with a known good relay (the horn relay). Refer to Cooling Fan Relay Replacement .
Does the cooling fan operate?
Go to Step 10  Go to Step 5 
5 Test the fan 1 relay and the fan 2 relay supply voltage circuits for an open or a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 16  Go to Step 6 
6 Test the fan 1 relay coil control circuit for an open or a short to B+. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 16  Go to Step 7 
7 Test the fan 2 relay coil control circuit for a short to B+. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 16  Go to Step 8 
8 Test the fan motor supply voltage circuit for an open or a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 16  Go to Step 9 
9 Test the fan motor ground circuit for an open or a short to B+. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 16  Go to Step 12 
10 Inspect for a poor connection at the harness connector of the fan 1 relay. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 16  Go to Step 13 
11 Inspect for a poor connection at the harness connector of the fan motor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 16  Go to Step 14 
12 Inspect for a poor connection at the harness connector of the powertrain control module (PCM). Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 16  Go to Step 15 
13 Replace the fan 1 relay. Refer to Cooling Fan Relay Replacement .
Did you complete the replacement?
Go to Step 16  -
14 Replace the fan motor. Refer to Cooling Fan Replacement - Electric .
Did you complete the replacement?
Go to Step 16  -
15 Replace the PCM. Refer to Powertrain Control Module (PCM) Replacement in Engine Controls LNK or Powertrain Control Module (PCM) Replacement in Engine Controls LV6.
Did you complete the replacement?
Go to Step 16  -
16 Operate the system in order to verify the repair.
Did you correct the condition?
System OK Go to Step 3