Faulty high speed fan relay (internal open or shorted coil); Damaged, chafed or corroded wiring in the relay control circuit between the relay and the PCM; Corroded or loose connector or terminals at the relay, fuse box or PCM; Blown fuse or poor power supply to the relay; Water ingress or heat damage in the power distribution centre or relay socket; Faulty PCM relay driver.

P1489

High Speed Fan CTRL Relay Circuit Open Or Shorted.

Dodge
Powertrain
Manufacturer code
Medium severity

How this code is built

P: SystemPowertrain
1: Defined byThe manufacturer
4: AreaAuxiliary emission controls
89: FaultThe specific fault in that area

What it means

P1489 on a Dodge means the powertrain control module has detected a fault in the control circuit of the high speed radiator fan relay. The module monitors the relay driver and saw a voltage state that did not match the commanded state, pointing to an open circuit, a short to ground or a short to voltage. The fault is in the relay control circuit, not necessarily the fan motor itself.

Symptoms

Engine temperature gauge climbing in traffic or at idle
Radiator fan not running at high speed, or not running at all
Fan running at high speed constantly, even on a cold engine
Air conditioning performing poorly or cutting out when stationary
Engine warning light on
Possible overheating warning or reduced engine power

Possible causes

Faulty high speed fan relay (internal open or shorted coil)likely
Damaged, chafed or corroded wiring in the relay control circuit between the relay and the PCMlikely
Corroded or loose connector or terminals at the relay, fuse box or PCMlikely
Blown fuse or poor power supply to the relaypossible
Water ingress or heat damage in the power distribution centre or relay socketpossible
Faulty PCM relay driverrare

How to diagnose

Read all stored and pending codes and note freeze frame data, including coolant temperature and whether the code is current or history
Check for other cooling fan, coolant temperature sensor or air conditioning codes that may point to a shared cause
Visually inspect the relay, its socket, the related fuses and the wiring for heat damage, corrosion, chafing or water ingress
With the engine cool, use a scan tool bidirectional test to command the high speed fan on and off and listen for relay click and fan operation
Check the relay coil resistance and swap in a known good identical relay to see if the fault changes
Using the wiring diagram for the specific model and engine, test the relay supply voltage, the control wire for continuity, and for shorts to ground or voltage
Check the PCM connector for pushed-out or corroded pins, then check the driver signal at the PCM only after the wiring is proven good

How to fix

Replace the faulty high speed fan relay with the correct specification part
Repair or replace damaged wiring in the control circuit, using proper soldered and sealed joints
Clean or replace corroded terminals and connectors and secure them properly
Replace blown fuses only after finding and fixing the cause of the overload
Repair or replace the power distribution centre if the socket or internal tracks are damaged
Replace or repair the PCM only if the driver fault is confirmed and all wiring and relay checks are good

Can I keep driving?

Medium severity

Short, gentle journeys are possible if the fan still runs and the temperature stays normal, but you should get it fixed soon. If the gauge rises or the fan fails to cool the engine, stop driving to avoid overheating damage.

Guide written by AI from the code's definition. Confirm with a diagnosis before replacing parts.