AU Fairmont Radiator fan won't stop + no heat from heater

Bulandgoose · 06-09-2011, 10:40 PM

I've been reading up on this thread http://www.fordforums.com.au/showthread.php?t=11319441
about the interior heater/demister fan not stopping. That sounds very promising and I'll have a look at that this weekend. However I need more help.

My story is as follows:
I've actually been given quite nice a 2000 model Fairmont by my brother-in-law for free, if I wanted to re-register and insure it, just so long as he could use to tow his trailer occasionally. They basically said it was a complete dog, but I might get a few miles out of it.

Actually, I think they fixed all its major issues before they got tired of it! (Well last one was the window switches, but I've fixed all those now)

Anyway, about 5 years ago, my sister-in-law came to me and said it was making a funny noise, even with the ignition off. Turned out the electric fan in front of the A/C evaporator was running all the time, so as an "emergency" fix I wired up a relay in series with the fan, so it would only run when the ignition was on. It's still wired up that way....

The other symptoms are
1. The heater/demister fan will only run at full speed, all other settings it just doesn't run at all. You can hear a relay click in when it goes top speed, so it's quite possible I have an open-circuit transistor instread of a short. I'll know more this Saturday.

2. The A/C works and all the various air redirecting thingies also work, but you can't get any heat, so it seems like whatever the thing is that lets the hot water through is not working. I've heard that on Commodores this can be caused by a faulty vacuum line, but I can't really make sense of what's under my hood.

Other that that, the car runs superbly so it would be fantastic if I could get this sorted out. "Of course, the Cruise Control is useless" sis-in-law loftily declared. Ah yes, but you have to turn it on first, dear! (The word "cruise" was worn off the indicator stalk and she don't believe in RTFM apparently....)

Also, can anybody tell me how you get the CD-Radio out? (Dead CD player, par for the course, but I'm hoping I can rig up a line input).

Thanks in advance for any advice, This forum is just what I was looking for

XRGhia · 06-09-2011, 10:52 PM

Quote:

Originally Posted by Keith Walters

I've been reading up on this thread http://www.fordforums.com.au/showthread.php?t=11319441
about the interior heater/demister fan not stopping. That sounds very promising and I'll have a look at that this weekend. However I need more help.

Anyway, about 5 years ago, my sister-in-law came to me and said it was making a funny noise, even with the ignition off. Turned out the electric fan in front of the A/C evaporator was running all the time, so as an "emergency" fix I wired up a relay in series with the fan, so it would only run when the ignition was on. It's still wired up that way....

Ok, so this issue will probably be caused by a faulty coolant temp sensor, or a dodgy relay... The relay's for the fans are located in the main fuse box in the engine bay next to the battery/ABS module.

Quote:

Originally Posted by Keith Walters

The other symptoms are
1. The heater/demister fan will only run at full speed, all other settings it just doesn't run at all. You can hear a relay click in when it goes top speed, so it's quite possible I have an open-circuit transistor instread of a short. I'll know more this Saturday.

I'd check the main transistor that's screwed into the heaterbox.

It's only two or three sockets, and two screws holding it in, and it can be accessed by removing the glovebox (un-clips from the dash).

I'll try to find a pic, but when you remove your glovebox you should be able to see a silver closed box with a few wires running into a small hole closest to the cabin of the car...

Quote:

Originally Posted by Keith Walters

2. The A/C works and all the various air redirecting thingies also work, but you can't get any heat, so it seems like whatever the thing is that lets the hot water through is not working. I've heard that on Commodores this can be caused by a faulty vacuum line, but I can't really make sense of what's under my hood.

Heater tap vacuum line has probably come off, and is just floating around the engine bay...

The heater tap is located underneath the intake manifold, but can still be very easily accessed from the top of the engine...

Just pop your head down the P/S of the engine bay, and right up the back near the firewall, follow the two black hoses coming from the heater core...

You should see a Gold or Silver round item that looks like it's suppose to have a vacuum line on it... If you look around that same area, you should see a small black or green vacuum hose that comes from the firewall... Simply pop that on the heater tap, then your heater should work...

Quote:

Originally Posted by Keith Walters

Also, can anybody tell me how you get the CD-Radio out? (Dead CD player, par for the course, but I'm hoping I can rig up a line input).

Is it the stock one?

If so, you just need either 4x very small phillips headed screwdrivers, or the proper keys to remove the CD/Tape player with....

You have to insert the screwdrivers, or the removal keys on an angle so that you are inserting them from about 10degrees into the middle of the CD/Tape player...

Hope that Helps...

Bulandgoose · 28-09-2011, 04:43 PM

Quote:

Originally Posted by xrghiawagon

Heater tap vacuum line has probably come off, and is just floating around the engine bay...

The heater tap is located underneath the intake manifold, but can still be very easily accessed from the top of the engine...

Just pop your head down the P/S of the engine bay, and right up the back near the firewall, follow the two black hoses coming from the heater core...

You should see a Gold or Silver round item that looks like it's suppose to have a vacuum line on it... If you look around that same area, you should see a small black or green vacuum hose that comes from the firewall... Simply pop that on the heater tap, then your heater should work...

Sorry, I can't really see anything at all from the top of the engine bay. The air intake thing has a large silver cover that covers almost the whole area. Would I be better off trying to look at it from underneath?

XRGhia · 28-09-2011, 05:06 PM

Yeah mate....

Jimmyd · 28-09-2011, 06:26 PM

Quote:

Originally Posted by Keith Walters

Sorry, I can't really see anything at all from the top of the engine bay. The air intake thing has a large silver cover that covers almost the whole area. Would I be better off trying to look at it from underneath?

V8???

Rambunctious · 28-09-2011, 06:38 PM

A crook thermostat is often the problem with the heaters not working in the 6cylinder AUs but not sure if the same applies to v8s.

Bulandgoose · 28-09-2011, 11:38 PM

Quote:

Originally Posted by xrghiawagon

Yeah mate....

Err... I'll have to wait until the rain stops for a while then....

Bulandgoose · 28-09-2011, 11:40 PM

Quote:

Originally Posted by Jimmyd

V8???

I wish!
Nope, just yer usual 4 Litre six.
I'm not really up on these things. I hardly ever drive the thing, and the last Fairmont I worked on was my 1967 XR 289 V8, about 25 years ago!
Things have probably have changed since then...

XRGhia · 28-09-2011, 11:44 PM

Can you get a pic of the engine bay just so we can see what's actually in the way? It might be removable....

Bulandgoose · 28-09-2011, 11:50 PM

Quote:

Originally Posted by xrghiawagon

Can you get a pic of the engine bay just so we can see what's actually in the way? It might be removable....

Yes, that's exactly what I was thinking: a couple of pictures might be worth a thousand words. Oh well, when the rain stops...

Also, regarding the fan speed controller, I pulled the glovebox out like you said, and I can see what might be the silver box you mentioned, but everything is crammed in there like sardines, and I can't see any mounting screws.
I've got a replacement transistor, now all I have to do is get the damned thing in there!

Rambunctious · 29-09-2011, 05:45 PM

With a 6 cylinder AU the heater tap can only be accessed from under the car on the passenger side of the engine.

Bulandgoose · 03-10-2011, 02:20 PM

Quote:

Originally Posted by Rambunctious

With a 6 cylinder AU the heater tap can only be accessed from under the car on the passenger side of the engine.

Yes, you’re right, the heater tap thing is in plain sight underneath, Unfortunately, the vacuum hose is attached, the piston moves freely, and it stays in until I take my finger off the vacuum tip, so the diaphragm is obviously OK. So that ain’t it….

I’ve taken the glovebox out, and after removing a lot of wiring harness clips I’ve been able to remove the two screws from the silver fan controller box, but there’s no way I can see of getting the thing out.

There’s no clearance between the box and some sort of black fan housing next to it. Also, it has two wiring looms permanently attached, and one disappears off under the dash somewhere so I can’t unplug it..

There’s two screws at the top of the glovebox compartment but taking them out seems to make no difference. I can’t see how the assembly comes out. Can anybody tell me the secret?

Bulandgoose · 09-10-2011, 09:29 PM

Progress!
I thought the A/C compressor was knackered because it made much noise and not much cold air. I wasn't going to worry about it but my wife insisted on taking it to someone who has heen "highly recommended" to her.
Well much to my amazement, $120 later it's been re-gassed and works fine.
And when it came back the heater was also working.
The guy said he could replace the fan controller for $100 using a second-hand unit, (reconditioned $400!). but it turned out to be the wrong type, so he returned it with that still unfixed.
He was in a hurry so he said he'd leave the wiring loom in a bit of a mess and fix it up when he had the right part. Because he did that, I was able to see a third mounting screw that was hidden by a big cable loom.

So I finally got it out, and there were actually TWO faulty transistors, the big one and the one that drives it. Anyway I replaced them both and now everything works. Woo Hoo!

$400?! I think I'm going to have a talk to these guys. The average repair would cost me about $10 to do (with a better than original transistor). I could make some seriious money here.

mik · 10-10-2011, 10:32 AM

good you got it sorted, the au has a few minor flaws but they are a top car if maintained properly.