To find it:
1. Consult your owner's manual: This is the best starting point. The manual should have a diagram showing the location of all relays and fuses.
2. Check the under-hood fuse box: This box is typically located near the battery, often on the driver's side fender well. Open the cover and look for a diagram on the inside of the lid. The diagram will show the location of relays and their function. Look for relays related to the cooling fan, A/C, or radiator. They might be labeled clearly, or you may have to check several relays by testing them with a multimeter (see below).
3. Check the interior fuse box: This box is usually located under the dashboard, often near the steering column or the driver's side knee bolster. Again, look for a diagram showing relay locations.
4. Identify the relay: Relays are usually square or rectangular components with multiple terminals. They are often larger than fuses.
Testing the Relay (If you can't find it by label):
If you've located multiple relays and aren't sure which one is the cooling fan relay, you'll need a multimeter to test them. WARNING: Disconnect the negative battery terminal before starting any electrical tests! A failed relay might be stuck closed, causing the continuous fan operation. Here's how you could approach testing:
1. Locate the cooling fan's wiring harness: This harness leads directly to the fan motor.
2. Check for continuity with the multimeter: With the ignition OFF, set your multimeter to continuity testing (often a diode symbol). Touch one multimeter lead to one terminal on the suspected relay and the other lead to another terminal. A good relay will show no continuity (no beeping). If the relay shows continuity (it beeps), this suggests it is stuck closed and is likely the faulty component.
Important Considerations:
* Multiple Relays: The Windstar might use multiple relays for the cooling fan system, especially if it has an A/C system. A faulty relay in the A/C system could also cause the fans to run continuously.
* Other Causes: A faulty PCM (Powertrain Control Module), a short circuit in the fan wiring, or a problem with the fan speed sensor could also cause the fans to run continuously. If replacing the relay doesn't fix the problem, further diagnostics are needed. A mechanic's scanner can read the PCM and help identify the fault.
Remember, if you're not comfortable working with car electrical systems, it's best to take your Windstar to a qualified mechanic for diagnosis and repair. Working with vehicle electrical systems can be dangerous if you're not experienced.
