Electrical Experts - rad fan & climate control questions

Vince_Hayduk

Registered User
I'm troubleshooting a "running a little too warm" problem on my '94. I know SCs run warm, but mine is getting up to the M in NORM and it's only 20C (70F) outside.

1) The automatic climate control works functionally as it should, but it won't turn off and the AC clutch is always powered (even when the control is in the "off" position). I've unplugged the AC for the time being because of problem #2, but obviously something isn't right here. The previous owner said he corrected a similar problem by replacing the climate control unit. Does the car have two lemon control units or is there something else that might be going on here?

2) My rad fan never turns on! It looks tired and doesn't turn easily, so I will be replacing it with one from a Taurus which people have said moves LOTS of air, but here is the part I'm not sure about: I have an scanner and it says that both the low speed and high speed fans are "off", yet the coolant temp was over 221 and the AC was on (see above) so at least the low speed fan should have been running. My question is this: when the scanner says "off" for a fan, does that mean the ECU hasn't set it to come on yet OR does it actually have feedback from the relays and it's telling me that I have a bad IRCM or wiring problem? The rad fan doesn't come on during the self test.

3) Should the pusher fan come on during the self test for a second? Mine does!

p.s. I know about cutting wire 14 on the IRCM. I am putting a switch in to achive that, but I also want to get the stock system working again!

TIA!

Vince
 
During self test, the relays are tested which should trigger all engine fans for a moment.

a bad low pressure sensor for the A/C could cause the fan not to come on with the A/C.

Try snipping the #14 wire and worry about the switch later. if the fan comes on, it's good. If it doesn't, the fan is shot. If you don't want to cut the wire you can instead jumper 12v to the fan plug to test it's function.
 
How did.....

How did you know the temps of the coolant is 221*???? Did you use a scanner????

I have seen VERY OFTEN the coolant sensor go bad. This will let the engine heat up and NEVER TURN ON the fans!!!!

Check the coolant sensor (very cheap to buy...get a Ford one!!!!) and then the deal. Could be the IRCM as they control the fan unit and the A/C in 94-95.


Don
 
also...

Check teh High current fuses in engine compartment for a blown fuse. The IRCM has its own I believe.

Don
 
Thanks guys!

I'm going to test voltage to the fan tonight. The relays click during the self test, so I'm assuming the IRCM has power, but I will verfiy that also.

I used my scanner to read the 221, so I'm assuming the CTS is fine. My scanner also says that both the low and high speed fans are off. This is why I was wondering if the computer has feedback from the IRCM for fan status.

Lube: For future info: when you've seen the CTS sensor fail, how do they fail?

Vince
 
Vince_Hayduk said:
I'm troubleshooting a "running a little too warm" problem on my '94. I know SCs run warm, but mine is getting up to the M in NORM and it's only 20C (70F) outside.


p.s. I know about cutting wire 14 on the IRCM. I am putting a switch in to achive that, but I also want to get the stock system working again!

TIA!

Vince

wheres this wire located? I see two orange wires on the IRCM, should i cut the orange one behind the plug down by the fan?
 
If the fan blades don't turn easily and the fans don't come on during the self test, plus on a 94/95 you've checked the 2 underhood fuses; then I'd say the fan motor is shot. As far as I recall it was the late model Escort that had the same 2 speed motor. I would do a search on this Forum to find the fan motor number (around $100) or you can buy one from Bill @ SuperCoupePerformance. Don't go to Ford for a replacement because even if they are still available, they only sell the whole fan & shroud assembly for about $400. When my fan motor went bad on my 94 it fried the fuse box and I had to re-wire it all using a fusible link (early models have the link and it's much better that way).
 
As I said, I'll be doing more checking once I get home tonight. I will test the fan motor and for power from the IRCM to the fan. I was going to go to the wreckers today to get a rad fan from a Taurus (which, according to Manny and others flows more air than an SC fan plus they are cheap and plentiful), but it's raining like mad here, so it will have to wait.

Merlon: I've read that you can't base it on wire color since they aren't consistant. You need to look for wire #14 on the IRCM connector.

Vince
 
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