The relay location and how to identify it
The radiator cooling fan motor relay in a 2000 Acura TL sits in the engine compartment fuse and relay box, located on the driver's side near the battery. Open your hood and look toward the left side of the engine bay — you will see a black plastic box with a removable cover. This is your main relay panel. The cooling fan relay itself is a small cube-shaped component, typically about the size of a sugar cube, with four or five metal pins on the bottom.
Inside the fuse box cover, you will find a diagram that labels each relay position. The cooling fan relay is usually marked as "FAN" or "COOLING FAN" on this diagram. In the 2000 TL, it is commonly located in position 5 or 6 of the relay bank, though the exact position can vary slightly depending on your specific model year and trim level. The diagram on the inside of the cover is your most reliable reference — match the label to the physical position before you remove anything.
The relay itself will have a part number printed on top. For a 2000 Acura TL, common part numbers include 39794-S84-A01 or similar Honda/Acura OEM relays. If you are unsure whether you have found the correct relay, the part number on the cover diagram will confirm it.
Key Takeaways
- The cooling fan relay is housed in the engine compartment fuse and relay box on the driver's side, next to the battery.
- The relay diagram printed on the inside of the box cover shows the exact position — match the label to the physical slot before removal.
- The relay is a small cube-shaped component with metal pins underneath, typically in position 5 or 6 of the relay bank.
- You can confirm the correct relay by checking the part number printed on top against the diagram label.
How to access the relay box safely
Before you open the relay box, disconnect the negative terminal of your battery. This prevents electrical shorts or accidental contact with live circuits while you are working. Use a wrench or socket to loosen the negative cable clamp — you do not need to remove it completely, just loosen it enough to slide it off the terminal post.
Once the battery is disconnected, locate the fuse and relay box cover. It is a rectangular black plastic box with a hinged or snap-fit cover. Gently pry the cover upward using a plastic trim tool or a flat-head screwdriver wrapped in tape to avoid scratching the paint. The cover will come free once you release the clips or hinges holding it. Set the cover aside in a safe place where you can still see the diagram printed on the inside.
Look inside the box and locate the relay positions. The relays are arranged in rows, and each position is labeled on the diagram. Do not touch any fuses while you are working — they are separate components and removing them by mistake can disable other systems like the fuel pump or ignition.
Removing and testing the relay
Once you have identified the cooling fan relay position, grasp it firmly between your thumb and forefinger and pull straight upward. The relay will slide out of its socket with gentle, steady pressure. Do not twist or rock it side to side — pulling straight up prevents damage to the socket pins.
After removal, inspect the relay for visible damage. Look at the metal pins on the bottom for corrosion, burn marks, or bent pins. If the relay appears burned or the pins are blackened, replacement is necessary. If the relay looks clean, you can test it by listening for a click when you explore 12 volts to the correct pins, though this requires a multimeter or test light and knowledge of relay pin configuration.
A simpler approach is to borrow an identical relay from a friend or parts store and swap it into the socket temporarily. If your cooling fan suddenly runs when you turn on the ignition, the original relay was faulty. If the fan still does not run, the problem lies elsewhere in the cooling fan circuit — the wiring, the fan motor itself, or the temperature sensor that triggers the relay.
When to replace versus when to troubleshoot further
If your cooling fan is not running at all, the relay is one of three likely culprits. The others are a blown fuse in the same box, a faulty coolant temperature sensor, or a wiring break between the sensor and the relay. Before you replace the relay, check the fuse first — it is faster and cheaper. The cooling fan fuse is usually labeled "FAN" or "COOLING FAN" on the diagram, and it sits in the same box as the relay.
If the fuse is intact and the relay looks clean, the relay is the most probable cause. Acura TL relays are inexpensive — typically between $15 and $40 for an OEM part — and replacement takes less than five minutes. If you replace the relay and the fan still does not run, you will need to check the wiring harness and the temperature sensor, which requires a multimeter and is beyond basic relay replacement.
If your cooling fan runs constantly even when the engine is cold, the relay may be stuck in the closed position. This is less common but still a relay failure. Replacement is the same process — remove the old relay and install the new one.
Installation of a new relay
Before you install a new relay, make sure the battery is still disconnected. Align the new relay with the socket opening, making sure the pins line up with the holes. The relay will only fit one way — the pin configuration is keyed to prevent incorrect installation. Push the relay straight down into the socket with firm, even pressure until you hear or feel a click. The relay should sit flush with the relay bank, not sticking up or sitting loose.
Once the relay is seated, replace the fuse and relay box cover by snapping or hinging it back into place. Reconnect the negative battery terminal by sliding the cable clamp back onto the post and tightening it with a wrench. Do not over-tighten — snug is enough.
Start the engine and listen for the cooling fan to engage within a few seconds. The fan should run for 30 seconds to a minute, then shut off as the engine warms up. If the fan runs when ready and continuously, the new relay is working. If the fan does not run at all, the problem is not the relay.
Common mistakes to avoid
The most common mistake is removing the wrong relay. Always check the diagram on the cover before you pull anything out. Removing the fuel pump relay or the main relay by mistake will leave your car unable to start or run. Take a photo of the diagram with your phone before you begin, so you can reference it if you lose track.
Another mistake is forcing the relay out of the socket. If it does not slide out smoothly with gentle upward pressure, stop and check that you are pulling straight up and not at an angle. Forcing it can bend the socket pins inside the box, which is expensive to repair.
Do not reinstall a relay that shows obvious burn marks or a melted plastic housing. A burned relay indicates a deeper electrical problem — possibly a short circuit in the fan motor wiring — and installing a new relay into that circuit will burn out the replacement. If the relay is burned, have the fan motor circuit inspected before you install a new relay.
Frequently Asked Questions
Can I replace the relay without disconnecting the battery?
Technically yes, but disconnecting it is safer. A stray touch against the relay box frame or a dropped tool can create a short circuit if the battery is connected. Disconnecting takes 30 seconds and eliminates that risk entirely.
What if the relay clicks but the fan still does not spin?
A clicking relay means the relay itself is working — the problem is downstream. The fan motor, the wiring between the relay and the motor, or the motor ground connection is faulty. This requires testing with a multimeter or a visit to a mechanic.
How do I know if the relay is actually bad or if it is just stuck?
A stuck relay will either run the fan constantly or not at all. If the fan runs constantly, the relay is stuck closed. If it does not run at all and the fuse is good, the relay is stuck open. Either way, replacement is the fix. You cannot unstick a relay — they are not serviceable components.
Is the 2000 TL relay the same as other Honda models?
Many Honda and Acura relays are interchangeable, but not all. A relay from a 2000 Civic or Accord may fit the socket, but it might not have the correct electrical specifications for the TL cooling fan circuit. Always use the OEM part number listed on the diagram or purchase a relay specifically rated for the 2000 Acura TL.
What should I do if I cannot find the cooling fan relay in the position shown on the diagram?
Check that you are looking at the correct fuse and relay box. Some 2000 TLs have a secondary relay box under the dash on the driver's side. If the main box diagram does not show a cooling fan relay, check the secondary box. The owner's manual will show both locations and their diagrams.