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Discussion Starter #1 (Edited)
I've got an '89 LX with the 2.3L. The cooling fan is not working, thereby causing the car to overheat if left to idle for extended periods such as bumper to bumper traffic.

I got the wiring digarams and I found that the absolute easiest thing to check was what alldata calls the "cooling fan temperature switch." According to the diagram this thing behaves as a simple switch, in the ground side of a relay circuit. Above a certain temperature, the switch closes and the fan comes on.

Any time the key is in the run position, If I bypass the switch directly to ground it should make the fan come on. I jumped across the switch to ground and the fan took off running like a champ. Bingo, problem solved, well problem found anyway.

I went to Advance (my first mistake I know) and they had a switch. It was an AC Delco part but of the three parts they had listed, it was the only one that even looked right. I bought the part and installed it without any trouble, well, almost no trouble. Now the fan runs any time the key is in the run position. Although this does effectively solve the overheating problem, it's highly annoying because it will likely dramatically shorten the lifespan of the fan.

Does anybody know of an aftermarket switch that will work?

The Delco part number was F1855. If I look it up at Autozone it lists a Wells TU25 which cross references to the Delco F1855. I don't really feel like the Delco unit is bad, but rather it's not the right part. I put an ohm meter on it and the resistance does go up as the car cools down, but it never gets high enough to not pick up the relay. It seems like what I have is a variable resistor when what I really need is a simple on off switch.

Is there a parts store solution or am I gonna resort to the dealership?

Thanks!

Edit - I called Ford and they would have to order the part, it is listed for $39!! The delco unit was $10. I find it really hard to believe that a technically less complicated device would cost 4 times as much. They gave me part number E7228B607A, alldata gave EOZZ8B607A, neither of these can I find any cross references to.
 

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As you've already found out, you'll pay more for the Motorcraft stuff, but if you think about it, that's probably the original temp switch in there from '89. Not a bad lifespan, so they must be doing something right (or buying the parts from someone who's doing something right). Anyway, I've had nothing but trouble from Wells repalcement parts. They'll work fine for a couple of months and then crap out. Coils, ignition modules, and especially sensors.

I haven't bought any firsthand, so I can't relate personal experience, but I've read here and elsewhere that NAPA's aftermarket replacement stuff is pretty decent. The price will be somewhere in between AZ and Ford.

As far as your theory goes, you're in the ballpark. It's just that some of the cheap aftermarket stuff doesn't perform the same way the OEM stuff does. They all change resistance based on sensor temp. Once sensor temp reaches a predetermined point, the resistance in the sensor is low enough to shunt the fan relay circuit and turn on the fan. As it cools down, the resistance increases, breaking the circuit and shutting down the fan.

You may have just gotten a bad switch. That's another characteristic of cheap parts. QC isn't there. They just stamp them out, box em and ship em. It looks just like a new part, therefore it must work like one right? Not always.
 

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buy a ford one. better quality anyway. the difference between the 2 part numbers is the one that ford gave you is an updated part number and sensor. ford changes what they put a part in so they change the number to the new model year number.E0 is 1980 and E7 is 1987.
 

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Oops. wrote the original reply, then reread your posts...

If with the switch manually shorted, the fan runs, that would seem to indicate that the IRCM is working. However, note that the IRCM has some other functions and logic, to accomodate the ac as well as the fan.

In any case, I would check out the IRCM circuit.

Based on the same problem I had when I got my 2.3 89 LX, I had written:

Probably not the switch at all. The "switch" is a temp sensor that goes in the engine. This engine has 3, one for the fan control, one for the EEC and one for the gage.

Most likely the problem is that the wiring harness that goes to the IRMC (Integrated Relay Control Module), the box under the dash with 8 wires in a connector going into it, has melted. The cooling fan relay or relays are in this box. They are on a circuit board, but can be removed from the plastic box. Battery power comes into it, to the relays, and power to the fan goes out. Its a long way for that much current to travel. The connectors apparently get dirty or tired and heat up. Then the plastic connector melts, as well as the plastic box that locates the connector to the circuit board, and then you get no connection. The fan wont run when called for by temp or for ac.

Ford and the aftermarket make a replacment wiring harness repair kit. Got one at Ford and one at Carquest. Melted the first one. Apparently I did not have a good connection, or my fan was drawing too much. I measured it at 35 amps plus. So I fixed the connector again. Later the fan motor died, and the one I put in has done just fine.

Fortunately, since my module was ok, I just added a pair of 30 amp relays in parallel to run the fan. The module now just controls the relay, requiring much less current through the IRCM.

Its worked for over a year, down the interstate, in traffic, 94 deg last Sat, idleing in traffic with the ac blowing nice and cold.
 

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I'm having the same problem. Fan on my 89 2.3l does not come on.

Does a Haynes manual cover the troubleshooting of the fan switch?
 

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As noted above, in my long winded post, the electric fan on a 2.3 has a lot more control stuff associated with it, besides the basic temp sensor.

There is no such thing as a fan switch, unless you mean the relays insde the IRCM or CCRM.

I have the Chiltons, and it was not real usefull except for the wiring diagrams.
 

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I just used a toggle switch and put it in the ashtray..only switch it on when in traffic...the other fan works normal when the ac is cut on
 

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My 89 LX 2.3 only has one fan, so I needed it to work as it was supposed to.

The current setup with the relays is working fine in 95 deg weather, in traffic and down the interstate.
 

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having the same problem with a 91 lx 23l daily driver. i live in so cal san diego. traffic and heat. my fan controller is one hundred dollars and on passenger shock tower. like toggle switch idea fan comes on at 210 degrees, cars has 235,000 miles with original head gaskets. i need to cool it.
 
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