heater playing up

[innes]

got a 525i and the heater is playing up, it has not got a/c. it gets fairly warm when direction is DOWN and blows very well. When direction is pointing towards upper body and face it still blows very well, but is cold?

also the rear windscreen does not seem to clear, any ideas guys?

[BillionPa]

AC control unit is fried, sounds EXACTLY like my car.

[innes]

I DONT have A/C tho

[DaveVoorhis]

What year is your 525i? It might be normal. My 1990 E34 does not direct heated air out the upper vents, only to the footwells or defroster vents. This is considered a feature.

[innes]

oh right???? mine is a 1991, you could be right!
any ideas on how to get my heated back screen working???

[DaveVoorhis]

oh right???? mine is a 1991, you could be right!
If you have a red/blue mixing knob on the center vents, then you can send heat to them. Otherwise not.


any ideas on how to get my heated back screen working???
Start by checking the fuses in the rear power distribution box under the seat.

[innes]

i have never seen that fuse box?? where, how do i get to it?

[shogun]

First of all, PLEASE complete you data with the car specs, month and year of production. If you cannot find that, use your VIN, visit my website and see under VIN decoder, there you find the engine spec, the trans or manual gear spe, the month and date of production. 1991 does not mean anything if we want to check in the wiring diagrams, exact month and year is required. It can be a 1992 model year, it can be a 1990 model year, and it could be a car produced even earlier.

Do a search (see top) for online owners manual and you will get to know where the fuses are. Study the owners manual, then study the wiring diagrams and then ask.
Lift the rear seat and habe a look underneath.
There is also a fuse box under the hood in engine room.

The back screen is controlled by the heating control module, and that is part of the amplifier which sits behind the C-pillar driver side. The 'lines' in the rear window are for radio antenna and for heating.

From Bill R.:

The upper 3 lines on the glass are the AM radio antenna, the middle 8 are FM and defroster, and the bottom 8 are defrost , if the middle 8 or bottom 8 have a break in the lines it will affect how fast it defrosts. You can buy repair kits that consist of a small bottle of metallic foil paint. Then you use masking tape to mask off each side of the line where a break is and paint a thin line to reconnect it... I used it before to repair defrost elements and broken fm antennas.
http://www.bimmernut.com/%7Ebillr/images/antenna.jpg

Check fuse 35 in the rear power distribution box under the rear seat and check the defogger relay k13 under the rear seat.


http://www.bimmernut.com/%7Ebillr/images/defogger%20relay.jpg

AND read this
http://www.bimmer.info/forum/showthread.php?t=20424&highlight=answer