Heaters Help!

[dontknow17]

Hi all,

I've bought an E39 523i 2000 not so long ago

When I finished work last night it was a bit chilly so I turned the heaters on for the first time and only got freezing cold air (engine temp at mid point).

The passenger side blowers will throw out a small amount of tepid air at low fan speeds but goes back to freezing at higher speeds. The drivers side throws out cold air at any speed. The air con is off and I tried at a range of temperatures on the climate control. I've never had dual zone before and it's confusing the hell out for me!

Any help would be greatly appreciated!

Thanks

Elliott

[Stevoc]

hey elliot..,ive got exactly same prob!!!! im sure its a sensor somewhere in engine bay.

my beemer is freeeezing just now :blink:

[Tarmacterror]

I had same problem on my 530 sport,I changed the radiator which was all blocked up from many years was told it was the original one! also replaced the thermostat and the heater resistor and it done the trick no problems after that. You could just try bleeding the cooling system who knows might just be a quick fix

[Stevoc]

Cheers TT.

I'm going to try bleeding the system first and see how that goes. Even the polar bears would avoid my Beemer first thing in a freezing morning! ⛄️

[Tarmacterror]

Hah I like that I love polar bears

If the first method isn't working then try the 2nd listed here.

How to bleed the cooling system.

1.Jack the front of the vehicle up onto stands as high as possible,

2.Turn the ignition on to Aux 2, Engine OFF, heater on fan setting 1 and temperature fully hot,

3.Remove the rad cap/expansion cap,remove the bleed screw from the radiator and IF you have them the bleed screw(s) from the thermostat housing/top hose, return pipe or EGR thermostat.

4.Fill the radiator/expansion tank up and keep pouring till there are no more air bubbles coming out from the bleeds, using a funnel that fits tight in the expansion tank neck and filling it full of water will help push any troublesome air out, when good you can then install the bleeds and tighten down(don't snap them),ensure the rubber O-rings/seals are still on the screws/on the bleed holes.

5.Suck some water out so it's not full to the brim, start the car up and check coolant shoots out of the small hole on the inside of the expansion tank neck when the revs are held up, if it does then replace the cap and then run the car up and check for heat from the vents when the car is warm, then carry on and check if over heating still persists. You may have to bleed troublesome cars again afterwards.(but very rare).

6.If all is good then check the water level again in the morning when cool.

or

Ignition on, heater set to hot, bleed screw out.

Pull the top hose off the radiator. Pour coolant SLOWLY down the rad hose a litre at a time. When the coolant is building up in the hose, hold it above the level of the rad hose stub and keep adding it. When coolant starts to dribble from the rad, refit the hose. You may find that coolant starts to overflow from the rad cap orifice - if it does, just screw the cap back on. Once you've done that, the engine and radiator are full of coolant - the little air pockets that might be left will come through the bleed screw.

After the vehicle is bled you should check that when the revs are held up you get a flow of coolant shooting out of the hole in the inside of the expansion tank neck, this will help tell you if the water pump is circulating, then run the car up and check the lower radiator hose gets hot.

[Stevoc]

Cheers again TT.

Was going to get onto to YouTube earlier but got all I need from your post. Very helpful indeed. Hopefully after bleeding I can ditch the thermals, wooly bunnet,duffle coat and survival suit every time I go for a drive. 😬

[Tarmacterror]

This is the benefits of joining the bestest beemer forum out there

Let me know how you get on mate

[Stevoc]

Yep I will do buddy. My mate gony let me use his double garage to keep out the elements!!!

Hopefully get it done this week. Thanks again👍👍👍

[Guest Mister Dabsy]

Obviously bleed all the system with the front of the car on ramps or high.... If that fails then its the heater resistor (hedgehog) or the electronic lower flaps lol

Hedgehog resistor failure is the most common

[Stevoc]

Cheers for the more insight Mr. D.

Defo going to get it checked out this week coz its artic up here just now!

[Guest Mister Dabsy]

How did you get on?

[Stevoc]

Well mr. D my buddy's wife thought it more important for him to go Christmas shopping for his three kids than to fix my Beemer!!!!

I know, unbielavable eh!!!

So rescheduled for Monday night. Fingers crossed. Will keep you posted 👍