Hi all

My fan is only intermittently working. I was wondering whether anybody has experienced this and how they fixed it please? Here are the symptoms:

- When the fan doesn't work, it is always from start up. However, the fan never cuts out when it's working.
- Switching it from speeds 1-2-3-4 and playing with the other dials does nothing.
- When the fan is working, it is almost always left on speed 3.
- I cannot precisely predict when it will happen, but it seems to happen more in the afternoon on hot days. The car is parked undercover all day.
- It has switched itself back on automatically twice. Once after a few minutes of idling a couple of weeks ago and again this morning on the freeway. With the exception of this morning, it was working the next day on start up when I drive to work.
- When working, there are no strange noises from the fan motor etc.
- The AC still works (green light on and I hear the compressor) and if I put the slider to 'fresh' and drop the window a tad, I get cool air above 70kph which is handy.:P
- All other electrics are working perfick.

I have performed a search of AMC and Google but can't quite pin point the answer to my car's problem. Some are saying BEM, ECU, resistor or fan motor etc. I think I have narrowed it down to a 'resistor' near the fan motor? but looking for confirmation as I want to fix it myself on the weekend. If it is indeed the resistor, is it easy to access and cheap to replace? I have replaced the fan motor in a Cressida before so I know they are usually situated behind the glovebox.

Any help appreciated. Thanks:)

Sounds like the Fan speed switch to me. Corroded contacts, bit unusual for this age of car, but not unheard of, Its quite possible that the fan has been set on 3 for some time, and the others areas are corroded,gunked over.

Either try some Blue CRC Electrical contact cleaner. Or arrange with a wrecker to get a refund if a Remove and replace don't fix it.
Sometimes a good back and forth off the fan speed switch for a minute or two may fix it temporarily, if thats a tempory fix a good clean or a R&R will required.

Check the fuse, replace it even if it is not blown as it will fix everything :confused:

This is sounding more like the relay to be honest, I would start there, swap the relay with something like your window relay, if this happens on your windows you know you have an issue. Relays are hard to test as once disturbed they often come good for a while as the coil is still fine, it is the contact that burns.

If you have a spare relay lying around by all means pop it in.

If this does not cure, I would not look at switch just yet, pop the facia out for a few days and next time it plays up check for power at the switch and then move around from there. These intermittant problems can be buggers to locate

Thanks guys for the help, I'll give it go!

Check your heater fan resistor

I reckon resistor symptoms would be a bit different: usually if its the resistor, you lose one fan speed (often the one you tend to prefer most) and other fans speeds are OK.

I suppose its possible that a resistor filament has burned-through, but occasionally still contacts...... but then at least some other fan speeds should be go-ers. Not the whole fan function being intermittent and on any speed setting.

Mal's suggestions sound like a good starting point.

Ok a bit of an update. The fan was working fine since my earlier posts so I didn't investigate in depth only for it to stop working again this afternoon. Tried flicking the fresh/recirculate lever side to side but with force and the fan started working! So yes it appears to be a contact problem within the HVAC controls and hopefully an easy fix if it repeats.