What Does P1489 Mean?
The PCM has detected a fault in the high-speed cooling fan control relay circuit. This indicates an electrical problem preventing proper operation of the cooling fan at high speed, which could lead to engine overheating under heavy load or low-speed conditions.
Common Causes
35%
Faulty high-speed fan relay
30%
Damaged wiring or corroded connector in relay control circuit
20%
Failed PCM fan relay driver circuit
10%
Blown fuse or fusible link in fan circuit
5%
Poor ground connection at relay or fan motor
Diagnostic Steps
1
Step 1: Locate and inspect the high-speed cooling fan relay for physical damage or corrosion
2
Step 2: Test relay operation by swapping with a known-good relay of same type
3
Step 3: Check for battery voltage at relay power supply terminals with ignition on
4
Step 4: Monitor PCM command signal to relay coil using scan tool or multimeter while cycling fan on
5
Step 5: Inspect wiring harness between relay and PCM for damage, shorts, or open circuits
Estimated Repair Cost
$100 - $400
Parts + labor, varies by vehicle and location
The PCM has detected a fault in the high-speed cooling fan control relay circuit. This indicates an electrical problem preventing proper operation of the cooling fan at high speed, which could lead to engine overheating under heavy load or low-speed conditions.
The most common cause of P1489 (High Speed Fan CTRL Relay Circuit) is: Faulty high-speed fan relay
Typical repair costs for P1489 range from $100 to $400, depending on the vehicle, location, and whether you do it yourself or go to a shop.
Continued driving may result in engine overheating, especially in stop-and-go traffic or hot weather. Monitor temperature gauge closely and stop if engine begins to overheat.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to P1489 to identify the root cause.
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Quick Info
Category
Powertrain
System
Engine Cooling System
Difficulty
Type
Manufacturer
Recommended Tools
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