Introduction
The radiator fan resistor controls the speed of your engine cooling fan. When it fails, the fan may stop working at lower speeds or altogether, causing your engine to overheat — especially in stop-and-go traffic. This guide will show you how to replace the radiator fan resistor on a Dodge Grand Caravan (and similar models such as the Journey, Ram 1500, Dakota, and Durango) with the resistor mounted on the engine bay fan shroud.
Safety Warning: Let the engine cool for at least 30 minutes after driving before beginning this repair. Engine bay components will be extremely hot.
Note: A failed resistor may show no visible signs of damage (no burn marks). Trust the symptoms — fan not spinning at all speeds, or engine overheating — rather than what you can see.
What you need
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Check for symptoms: fan not spinning at all speeds, engine overheating (especially in traffic). Open the under-hood fuse box (near the battery). Find the cooling fan fuse using the lid diagram or owner's manual.
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Red: Cooling Fan Fuse
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Park the vehicle on a flat surface and apply the parking brake. Turn the engine off and open the hood.
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Gather your tools: 8mm socket and ratchet set with extension, 10mm wrench, work gloves, and the new replacement radiator fan resistor (matched to your vehicle year and model).
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Pink: Radiator Fan Resistor
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Blue: Ratchet Extension
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Red: 10mm Wrench
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Orange: 8mm Socket
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Yellow: Work Gloves
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Look into the engine bay and locate the radiator fan assembly. The radiator fan resistor is mounted on the LEFT side of the fan shroud (the black plastic housing surrounding the fan). It is a small rectangular component with two screws and a wiring harness connector attached.
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Pink: Radiator Fan Resistor Location
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Red: Engine
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Blue: Battery
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Green: Radiator
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Locate the wiring harness connector on the resistor. Press down on the locking tab (the small plastic tab on the side of the connector) with your thumb while gripping the connector body firmly. Pull straight out — do not pull by the wires. The connector should release smoothly.
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Blue: Wiring Harness Connector
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Using your 8mm socket and ratchet with extension, remove the two mounting screws holding the resistor to the fan shroud. Tip: If the screws are rusted, apply a small amount of penetrating oil (WD-40 or PB Blaster) and wait 10 minutes before removal to avoid stripping.
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Blue: Mounting Clip
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Yellow: Radiator Fan Resistor
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Pink: Engine
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After completing the repair, start the engine and let it warm up to normal operating temperature. Watch the radiator fan — it should spin up automatically as the engine heats up, with the fan running at varying speeds depending on temperature. The dashboard temperature gauge should stay in the normal range. If the fan still does not operate correctly, use the diagnostic flow chart below:
Fan works → Success!
Fan does not work → Check that the connector is fully seated
Fan still does not work → Check the cooling fan fuse
Fan still does not work → The fan motor itself may need replacement
Congratulations! You have successfully replaced your radiator fan resistor.