306 heater/air con fan

[Stone Free]

Guys, I need some suggestions as to what is wrong here. My heater and air con fan is being very tempremental. Sometimes it works, sometimes it doesn't! There is no rhyme or reason to it. I have checked the fuses; they are all okay. Sometimes it works okay when I start the car and then just stops, sometimes it doesn't work when I start the car and just starts! Can anything be done??

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[Paltallo]

Hi Stonefree and fellow froggers,

The fans, air con etc in my 2001 306 Rallye are a tad annoying!

1) The fan always seems to be on (just slightly) even when the switch is in the off position.

2) The air con sometimes comes on automatically no matter where the switches are set - supposed to turn on automatically if in demist position and the fan is on if I recall correctly. Really annoying as well because the light on the air con switch is barely visible in daylight! Its come on a few times and I haven't realised cause the window was down and/or the sunroof open - does wonders for the fuel economy!

3) My other niggle is with the feet setting - most of the air still comes out of the top vents!

Is this all normal on a 306?

Great car otherwise

[immy s16]

Guys, I need some suggestions as to what is wrong here. My heater and air con fan is being very tempremental. Sometimes it works, sometimes it doesn't! There is no rhyme or reason to it. I have checked the fuses; they are all okay. Sometimes it works okay when I start the car and then just stops, sometimes it doesn't work when I start the car and just starts! Can anything be done??

There are 3 fuses between the fans in a small triangle box have you checked those

[immy s16]

Sorry just relised that you may be talking about the inside fan, in that case check the connections, its located behind the glove box you can get it out from the bottom.

Cheers

[Stone Free]

Sorry just relised that you may be talking about the inside fan, in that case check the connections, its located behind the glove box you can get it out from the bottom.

Cheers

Cool, I was wondering where it was!!

[Stone Free]

Actually, I dunno if it is the fan connection per se. Nothing works on the panel at all; even if you press the a/c button or the recirc button that doesn't even come on either. It is definitely a connection somewhere. Anyone got a wiring diagram they can help with?

[immy s16]

have you checked the fuses in the engine bay not sure if there is anything in there about fans but it worth a check.

Also those square type fuses(forgot what the call them) in the fuse box under the steering wheel, check to see if they are working.

[XM Mechanic]

Hi Stonefree and fellow froggers,

The fans, air con etc in my 2001 306 Rallye are a tad annoying!

1) The fan always seems to be on (just slightly) even when the switch is in the off position.

Allows the air to circulate slightly so the sensors "feel" what temp the air is and it decides where to go from there.

2) The air con sometimes comes on automatically no matter where the switches are set - supposed to turn on automatically if in demist position and the fan is on if I recall correctly. Really annoying as well because the light on the air con switch is barely visible in daylight! Its come on a few times and I haven't realised cause the window was down and/or the sunroof open - does wonders for the fuel economy!

It does that. It knows its hot and it just wants you to be cool

3) My other niggle is with the feet setting - most of the air still comes out of the top vents!

It wants to share the air!

Is this all normal on a 306?

Yep, sounds like the wonderful 306 climate control. Best dang climate control I ever experienced.

[XM Mechanic]

Actually, I dunno if it is the fan connection per se. Nothing works on the panel at all; even if you press the a/c button or the recirc button that doesn't even come on either. It is definitely a connection somewhere. Anyone got a wiring diagram they can help with?

I'd start by having a look at the connectors at the back of the A/C controls. Unplug and then replug them. You can pry the front panel off and then access the two retaining screws.

Good luck.

[Stone Free]

Allows the air to circulate slightly so the sensors "feel" what temp the air is and it decides where to go from there.

It does that. It knows its hot and it just wants you to be cool

It wants to share the air!

Yep, sounds like the wonderful 306 climate control. Best dang climate control I ever experienced.

XM: That's what mine USED to do, like it is supposed to. To get around the fan always being on I just set it to demist and feet so I didn't continually have a breeze blowing in my face

But yes, I am going to have a look behind the control panel this weekend. However, I did speak to Justin at Justin Fisher auto last night and he mooted that it could be the circuit board which costs something like $900! Just my luck. But then, if it was that, I would assume that something would work, but as it is, there is no power at all getting to anything.

[XM Mechanic]

Stonefree,
I hope its the simple fix for your sake. If you want to try something that may or may not work. Try disconnecting the battery for a couple of minutes as a "master reset" for the climate computer.
If you get access to the elect connectors try giving them a spray with a WD40 type substance. (just a little). It might sound a little strange, but a few years back my 306 reverse lights didn't work. All the components worked, globes,wiring and switch. I studiously cleaned the switch connector on the gearbox with electrical cleaner several times with no joy. I asked an electrician where I work and he came out with some Maxsolve 200 spayed it connected it and it worked immediately.
That would have been the last thing I would spray into an elect conx. However I was proven wrong and it has worked successfully for me several times since. Globes, microphone connectors, XM engine management connectors etc.
Apparently the connection gets a waxy film or corrosion on them and electrical cleaner won't get it off but the Maxsolve makes the joint conductive again.

Goodluck and cheap fixes.

[SLC206]

I had this problem on my 306 XT for a while (surprised XM Mechanic didn't mention it - his memory must be going to mush).

I pulled the fan motor out of the dash (it's under the glove box somewhere) and lubed up the bearing and it was very happy for the rest of the time I owned the car.

Of course your problem may be a little different...

[UKGraham]

Don't know if this is quite the same thing... but the climate control on my '98 406 recently stopped being automatic.

I've got a working fan when I use the manual control and temperature seems to follow what I set it too - just no automatic fan response.

Noticed this morning - in demisting mode nothing happens. Manually get the fan going and hitting the demisting button turns the fan back off / down.

What do you reckon - fuse? connector?.... jack up the mirrors and fit another 406?

[Stone Free]

Stonefree,
I hope its the simple fix for your sake. If you want to try something that may or may not work. Try disconnecting the battery for a couple of minutes as a "master reset" for the climate computer.
If you get access to the elect connectors try giving them a spray with a WD40 type substance. (just a little). It might sound a little strange, but a few years back my 306 reverse lights didn't work. All the components worked, globes,wiring and switch. I studiously cleaned the switch connector on the gearbox with electrical cleaner several times with no joy. I asked an electrician where I work and he came out with some Maxsolve 200 spayed it connected it and it worked immediately.
That would have been the last thing I would spray into an elect conx. However I was proven wrong and it has worked successfully for me several times since. Globes, microphone connectors, XM engine management connectors etc.
Apparently the connection gets a waxy film or corrosion on them and electrical cleaner won't get it off but the Maxsolve makes the joint conductive again.

Goodluck and cheap fixes.

Won't this reset the ECU and screw everything up?? I'm going delving behind the dash tomorrow to see what I can see. Will get some WD40 to try out too!

If I do an ECU reset, what do I need to do once it is all connected again?

[XM Mechanic]

Won't this reset the ECU and screw everything up?? I'm going delving behind the dash tomorrow to see what I can see. Will get some WD40 to try out too!

If I do an ECU reset, what do I need to do once it is all connected again?

IMHO I don't believe it will be a problem. What happens if you have to change your battery? When it goes to a panel beater (hopefully never) they will disconnect and reconnect the battery during repair. The ECU should reset to defaults if it doesn't have a memory.

[SLC206]

Won't this reset the ECU and screw everything up?? I'm going delving behind the dash tomorrow to see what I can see. Will get some WD40 to try out too!

If I do an ECU reset, what do I need to do once it is all connected again?

I'm not convinced that disconnecting the battery will "screw everything up" but I did have a dealer once that insisted on doing something with the idle stepper motor whenever the battery was disconnected.

I'm sure there are others here with more info on the 306, but I think your ECU will just relearn your driving style once again, that is all.

[SLC206]

Won't this reset the ECU and screw everything up?? I'm going delving behind the dash tomorrow to see what I can see. Will get some WD40 to try out too!

If I do an ECU reset, what do I need to do once it is all connected again?

I'm not convinced that disconnecting the battery will "screw everything up" but I did have a dealer once that insisted on doing something with the idle stepper motor whenever the battery was disconnected.

I'm sure there are others here with more info on the 306, but I think your ECU will just relearn your driving style once again, that is all.

[Stone Free]

OKay, well, here is the story of my heater/air con from the weekend:

Friday night: Not working at all.

Saturday: Not working in the morning, after driving around for a fair bit of the day it started working while I was driving. Kept going for the rest of the day.

Sunday: Worked first thing when I started the car. It then stopped working about 10 minutes into the drive and hasn't workled since.

I didn't get a chance to get inside the control panel to see if there was any loose connestions. This is driving me bonkers!!!!!!

[Stone Free]

OKay, well, took out the centre console bit as best as I could. The connections all seem to be fine so back to square one.

I should point out also that when it decides to work, especially when driving, I hear a small click from the fuse box under the steering wheel. Could it be related to one of those big square cube looking fuse things?? I have no idea what they are or what part of the car they look after. I don't really want to go pulling them out as I don't want to screw anything up.

Suffice to say it might have to be a trip to Mr Mechanic for this one.

[immy s16]

Those big square things are relays, just try swapping them around if they are the same,

If not you will have try and find out which one is clicking and replace that one.

Prob wouldnt hurt ringing your mechanic and asking him what relay does what.


Cheers

[Stone Free]

Ahh yes, a relay! It could be the source of all my woes!

Which one is in charge of the climate control then? Where can I get replacements??

[immy s16]

Ahh yes, a relay! It could be the source of all my woes!

Which one is in charge of the climate control then? Where can I get replacements??

Not sure which one controls the fans, but as for sourcing them just take it down to your nearest auto electical supplier and they should have them there, from memory going back about 2 years ago i paid $10 for one, dont see them been to much more than that.

Cheers

[Denis]

Guys, I need some suggestions as to what is wrong here. My heater and air con fan is being very tempremental. Sometimes it works, sometimes it doesn't! There is no rhyme or reason to it. I have checked the fuses; they are all okay. Sometimes it works okay when I start the car and then just stops, sometimes it doesn't work when I start the car and just starts! Can anything be done??

I could almost guarantee that the problem you have will be faulty earthing (or faulty connection) on the thyrsitor speed control unit for the blower motor. I just repaired the unit on my daughter's 205, a couple of years ago I repaired the connections to the unit in my 405 (that unit is onboard with the motor), and many years ago now I repaired the earth on the same unit for a 505 wagon that I had.

Now I haven't checked out the location for a 306 (the blower in my wife's 306 works fine ) but it's either on the fan motor itself (in which case one of the quick connectors will have been overheating) or nearby (slotted into the air flow near the blower).

BTW, the click you hear when the unit works correctly is an associated relay picking up .. at other times, there is not enough voltage for the relay to pick up.

Denis

[Stone Free]

Thanks for that Denis. I am up for trying anything at this stage, but I would have no idea how to get into the fan unit. It is under the glovebox and after having a look under there the otehr week, I am not even going to touch it. So long as it isn't the printed circuit board I'm happy.

As a side note, I was driving around last night when it came on again, only for 5 minutes or so, then stopped. Only seems to happen now when the car has been driven for an hour or so.

[Denis]

Thanks for that Denis. I am up for trying anything at this stage, but I would have no idea how to get into the fan unit. It is under the glovebox and after having a look under there the otehr week, I am not even going to touch it. So long as it isn't the printed circuit board I'm happy.

As a side note, I was driving around last night when it came on again, only for 5 minutes or so, then stopped. Only seems to happen now when the car has been driven for an hour or so.

All these symptoms are those of a faulty connection to the speed controller or the blower itself. OK - so I just had a look under the dash of my wife's 306. It looks like this blower has an on-board speed controller (like the 405). The blower is on the LHS under the dash and is held in place with three torx screws. There if a plug connection to it with three wires ... my guess is that this plug will be the likely problem ... or it could be on-board. However it is pretty easy to remove the fan, disconnect the plug and look for overheating spots. If the plug connector has overheated, it is usually sufficient to clean back the terminals and re-connect (squeeze a quick connector with a pair of pliers to restore some contact pressure). And it would be as simple as that.

Denis