Radiator Cooling Fan fuse location

Hello, the cooling fan fuse is Fuse # 9, 40 A, battery junction box, underhood. Here is a guide to help you check for power and the fuse location below with the cooling fan wiring diagrams to help you see how the system works. There are control relays that should be checked if the fuse is okay

https://www.2carpros.com/articles/how-to-check-a-car-fuse

and

https://www.2carpros.com/articles/how-to-check-an-electrical-relay-and-wiring-control-circuit

Check out the diagrams (Below). Please let us know what you find.

Thank you will try it and see if that will fix it

You're welcome. Hope it is an easy fix otherwise you would need to test the fans and controls etc which can be rather time consuming.

ok thanks agian will let you no if it wirks

well did not work don't no what to try next the fan motor bad?

I found this guide I think I will check for power at the motor.

https://www.2carpros.com/articles/replace-electric-fan-motor

Do the fans run when A/C is turned on?

Item # 24 is the low speed whereas # 32 is the high speed fan relay. I have the schematics here for you. Go through get an understanding of the system. Note where the Engine Coolant Temperature sensor is as we might need to do some test there.


Get a test light or DVOM and we can get cracking to diagnose the problem.

the fans do not run when A/C is turned on
do not come on at all thanks agian

Since both fans are not working, lets do a simple test first.

Start engine and turn A/c on. Give both fans housing some light knocking with a mallet or anything that can produce some slight vibrations. Note if any fan comes on. If they don't, continue with next step.

You would need to test the fan motors first. Fan motors do not fail simultaneously but there is a possibility one failed and was not noted until the next one failed.

Unplug the wire connector and apply battery voltage to the Red/Orange terminal of the fan motor and ground the other terminal. If fan works, they are good. Alternatively you can test the resistance of the two terminals with an ohmmeter. No continuity indicates a failed motor.

Stop engine. Unplug the wire connector of either one cooling fan and test for battery voltage at the Red/Orange wire with engine running and A/C turned on.

If you have battery voltage, use a jumper wire to ground the Black wire and see if the other fan works.

ok will try the fan motor and let you know.

I upgraded this question, because I have the exact same problem on my car. I lost AC last year, and this week had to replace the water pump, after I noticed that the fans aren't turning on at all when you put on the AC and it eventually led to a broken water pump impeller. My car is a 1998 Mercury Sable LS DOHC. I tested the plug going to one of the fans, and with the AC on, I couldn't get any voltage or amperage to the fan itself. I believe both fans work, though they are a pain to even attempt removal, let alone test.

What is the relays for this car, as lat's car has a different box diagram than mine. Oh and the radio loses sound when I put it in reverse. That might also be an issue.

1998 has a different fuse box design and the schematics are slightly different as well.

Radio losing its sound could be due to a bad ground circuit somewhere and it most probably should be around the radio.

Thanks for being online today, thought I'd have to wait til tomorrow to find out which relay to test. On that note, how do I test relays for cars. Last time I did it, I blew one up, and had to replace it anyhow. The fuses are good, I should probably test the fans themselves, but since they're not getting power, I'm assuming 1 or both relays is shot.
Would there be anything else to test if the relays are good?

I added an image to clarify the 2 relays.

Actually I was about to log off for the day.

If you refer to the wiring diagram, yyou would notice that the relays are labelled 30, 85, 86 and 87 for the terminals.

You relay is labelled differently and has 5 terminals. The center row is actually terminal # 30 (single pin) while the other 2 pins are terminal # 87. One of your relay has the wordings 2,4, 3, 5.

@ and 4 are the coil circuit whereby if battery voltage is applied to one and and the other is grounded, the relay would click.

One simple way is to sway the relay with another that fits, eg the headlight relays. You can use the headlight to test the realy too. Just remove the headlight relay and plug the fan relay in and turn on the headlights. If the headlight fails to work, then you would know the relay is bad.

I did the simple way, and both of those worked. I swapped the relay for the fuel pump and I still had fuel pressure, and checked just in case, and pulling it caused the car to stall.

Likewise I swapped the relay for the starter relay and pulling that wouldn't start the car, but both relays allowed the car to start, so that relay is good.

Now what should I do?

Sorry I made an error with the relay teminals. Terminals 1 and 2 are the coil whereas 4 is the power supply and 5 and 3 are the output.

Unplug the relay and check terminals 3, 4 and 5 of fuse block for battery voltage. Depending on which relay, low or high speed fan, there must be one terminal that is hot at all times. If terminal 4 has battery voltage, use a fused wire to connect it with either terminal 3 or 5 and see if fan comes on.

If I'm doing this correctly, according the the numbers on the relay itself, corresponding to the holes on the fuse block, starting with the red wire plugging in from position 3.
3 to 5 gives me 12 volts.
3 to 1 gives me 12 volts.
3 to 2 yields 0.25volts.

There is no metal prongs in position 4 on the smaller relay for the center #4 position.
If I'm not connected to position 3 (the farthest lead not in line with 3 prongs, I yield no voltage for say 2-1 or 5-2 or 5-1.

Likewise on the fatter Relay, holding on position 30, I get 12 volts on position 86 & 87, 0.5 volts on position 85, and center 87A is unused. No voltages present if one lead is not on position 30.

So I checked with the fuseable link, and was enable to engage the AC clutch first with the car off, with a junction between 3 and 5 of the single separate leads. But, if you don't put the small AC relay back in place it blows the fuse while your testing the big relay. So, once I put that back in, and engaged 30 & 87 I was able to get both fans to spin at a normal speed. Any other position yielded no results on both circuits.

Actually when you are testing for battery voltage, you probe the terminal that you wish to test and ground the other probe to a ground.

I would like you to perform the above test again to confirm the main power supply from the fuse as the wiring schematic seems to be rather confusing. Mark the 2 wires, one for each relay. Repeat testing with other terminals with ignition switch turned on. This is for getting the power source of the relay coil.

Just want to make sure which is which.

The test indicates the fan motors and wiring circuit are good and now we would have to test the relay coil, to see if it is power supply that is missing or you have a fault with the grounding circuit for energising the relay. These are controlled by the PCM so hopefully that is not the cause.

Working with Ground, Position 30 & 86 both carry a voltage between 11.75 (key on) and 13.50 (engine on) Other two terminals show no response either way. Likewise position 3 & 2 on the smaller relay for the A/C Clutch have the same volts each (key on) and engine on respectively.

The relays are not being energized due to command from the PCM is missing.

Can you ground terminal 1 or 85 with a test light with relays plugged in and ignition switch turned on. If the fans comes on, you have a problem with the PCM .

I'll have to get a new test light for that test. I blew mine up last year working on a headlamp for another car. I'll get back to you when I've done as you've requested.

I will be away for a day or 2 so my next reply could be delayed.

No problem, I gotta go to SEARS a few towns away to get the test light.

I did as you asked, and the light came on, and so did the fans.

However there was one thing to note, I had an SES light on, which in my car isn't normally a cause for alarm but I had the opportunity to go to Autozone just to see what they said, and they had 1 code: PO117. Unfortunately when I replaced what I thought was the offending part with a pointy engine coolant sensor (pic1) from a cylinder one (pic2), I get no signal to my dash board coolant gauge. I wonder if I need to replace a different sensor, and if so where is it??? The gray cylinder one I replaced (erroneously I believe now) was located by the Y-pipe, under a wire harness, below the air cleaner, stuck into an aluminum heat pipe.

Was this done prior the problem?

ECT are sensitive and the correct part should be replaced. Substitutions do not work.

There are 2 sensors, the ECT sensor and ECT sending unit.
Sensor is for the PCM to monitor the engine temperature whereas the sending unit is for the tempature gauge.

What you have replaced should be the sender which is for the temperature gauge.

The one producing the code is item 14 in diagram, should be the one you described. Check the unit wire harness for proper connections.

The ECT is part of the cooling fan system component and if there are any fault with it, the fans might not come on.

After the water pump had the impeller crack and it took me 3 days to get the new one installed, I hadn't driven it around until that day, so no the problem with the sensor wasn't noticed until after I was checking to see if the new water pump actually worked. The rub was, the SES light came on, and yet my gauge on the car's dash seemed to be fine. So It looks like I need to switch back the old part in, and put the other thing into another spot. (((I don't have the 3.4L SHO, I have the 3.0L DOHC)))

The component locations are similar.

Alright we'll crack it open. Thankfully I haven't driven it today.

It's located under number 8. Down under the air intake manifold, and just below the PCV elbow.

Hope that solves the problem.

It did. Thanks ever so much. I still think the ECT Sensor might be a little lazy, it gets only so high, unless it goes up to super red as it did when the water pump failed. But it was the Sender Unit that was defective, not sending a signal to the PCM to turn on the fans. Since the ECT is only $10 worth replacing to see.

The A/C still doesn't work, just won't come on at all. It has the proper pressure, and if I ground terminal 1 the AC Clutch spins, but still don't get cool air into the cabin. There's no squeal or anything from the Compressor, but as well if I put it on AC or Max AC, the fans don't come on doing so. But at least the fans do spin now when I am sitting at a stop light on a hot day. Hopefully this keeps up.

Have the A/C freon checked. Let me know the static pressure.

They had it at 20 psi I guess for a static pressure. As it turned out I had good vacuum, and no leaks, apparently the R-134 leaks out over 12 years through the hoses, as even with a UV test he couldn't find anything leaking from anywhere, and since I only had 4 oz in the system, they charged it up with 2lbs and now it works, just as it once did. I suffered for 2 years for nothing. Even the fans come on now, when you hit the AC button.

So then the last thing that occurs, before I move on to other cars. I cannot for the life of me figure out. No codes appear for this one, but whenever I go up hill, or turn the AC on, the car has a engine stumble, it'll idle at 1250RPM and rumble a bit, and then drop to 1000RPM, and recover every 2-3 secs while sitting at a stop light. If I turn off the A/C it doesn't do it as much, but it's still somewhat present. This has been going on for many years, and I've been at a loss to figure it out. I replaced the fuel pump, fuel filter, screen, had the tank cleaned out, and replaced the canister and purge valve on the pack that's under the trunk. The plugs are platinum, the wires are good, and it drives down the highway fine, just likes to rumble at stop lights and lacks power up hill.

(I double-down my donation, did you get that?)

Thank you for the donation.

For pre-year 2k models, sometimes misfiring codes are not detected and from symptom descripption, there is a possibility the spark plugs needs attention. It could be the wires are loose or has bad conductivity due to rust formation at the sockets, etc. Misfiring or hesitation under load are mostly due to sparks ignition faults.

Since you do not have any trouble codes, a scan tool to monitor the sparkings might show something.

I did have a funny problem, that were the wires long ago. Whenever I stopped at a toll booth, the car would run rough, and then die as soon as I hit the gas. I'd have to restart in order to go. I replaced every gasket, vacuum tube, hose, clamp, you name it, even did the plugs, coil pack, everything. But it turned out the wires had gone. Oooh that really sucked not having done that, but doing the Coil pack instead.

I've wondered if I've got a lazy Crankshaft position sensor. My dad's car has a similar issue, though his car won't start good, and takes maybe 12-15 tries to get going, and then it runs like crap. Going to take that back to the tranny place on Monday to have a look. I'm think his problem is similar to mine, but a good wire set every 5 years is probably worth the investment.


What would a scan tool for sparkings look like?

Scan tools comes in various grades. A simple one would be just a code reader. Average ones would come with simple functions for testing components. A high end scan tool would come with PCM, immobilizer resettings and many other features that allows you to monitor and/or test the various components that is PCM or BCM controlled. You can read the datastream of the various sensors etc.

Is there any brands/models to choose from. Or at least the word to look up on Google shopper to get what I need?