Help with auto climate control, schematics?

[k.alle]

Well, I stand corrected. Been to the car and thought I would bridge D16 & D14 but did a last measurement.
D16 is in fact a small brown/black wire, D15 & D14 is thick brown as stated in schematics.

However, D16 functions as earth when I use the multimeter and D14 & D15 (which is supposed to be earth) is dead..
Is this normal, will try to find out if D16 i supposed to be earth or if something is way off.

Didn't dare to bridge D16 with D14 & D15 for the record.


EDIT:
D16 seems to go to radiator fan relay, don't think I should i should bother about that one.
Will try to put a new earth in both D14 & D15 tomorrow and see how it goes

[k.alle]

I'm a moron.
Tested the earth D14 & D15 the correct way, measuring resistance bewteen earthpoints - D14/15 - battery negative and body, all showed 0 Ohm and buzzed nicely.
So I don't know what the hell I've been measuring yesterday, I think I've switched red thingie on multimeter with black thingie and measured the wrong way if that makes any sense?

Anyway, confirmed good earth at D14 & D15 so it's not (?) an earth problem.

What should I do next, measure all the pins on the back of the AC controller again?
Using D14 or D15 as earths obviously.

As a side note I probably should mention that trip computer and dash clock is not working either now. And electric windows intermittently off..
Is this related or separate gremlings?

Thank you all that has helped before and anyone kind enough to give me some help now

[UrS4boy]

Ignition Switch info

What is the condition of the electrical portion of the ignition switch? With the C4 UrSs, a bad/broken spring in the switch does not return to the proper "RUN" position after starting, leaving many circuits still connected to the load reduction relay, i.e. not powered. This switch failure will also stick the starter in ON even after the engine has started, killing the starter dead due to overspinning.

Worth checking or at least wiggling the key to see if you can get power to some of these unpowered devices.

Here is an example (C4 UrS) ignition switch replacement DIY (B3/B4 will be similar):

http://12v.org/urs/IgnitionSwitchReplacementDIYRev1.pdf (Edited to the updated version)

[k.alle]

It doesn't get stuck in starter-motor-mode but It does not retract to Ignition ON mode all the way. If I want to I can help it back so to speak.

Can I check It in some definite way other than wiggling the key?

Really good advice here.

[UrS4boy]

It doesn't get stuck in starter-motor-mode but It does not retract to Ignition ON mode all the way. If I want to I can help it back so to speak.
Can I check It in some definite way other than wiggling the key? Really good advice here.

If it is not returning to "ON" from "START" without assistance, it is very likely that the switch plastic has broken and the internal spring is not working properly to pull the key back to "ON" properly.

Here is the link to the revised switch DIY that I did in February of this year. Note on page 12/14 what a broken switch looks like. The PNs for the B4 switch are very likely the same as the C4 switch, unless you have an immobilizer, in which case, I don't know the PN or how the immobilizer works.

http://12v.org/urs/IgnitionSwitchReplacementDIYRev1.pdf

These are the B4 ignition switch PNs that I found (but they are for the USA = no immobilizer):

[k.alle]

Well I do have Immobilizer but I'm 99% it was fitted when imported to Sweden, so I believe I have the non immobilizer version.

Awesome guide by the way, will be of great help when I attack this issue
So if the ignition switch is acting up it can cause these issues that I am having?
I have also heard of an x-relay ?

Great info and help as usual UrS4Boy!!

[k.alle]

European KATE tells me ignition switch
4A0 905 810B is for cars >>8B-R-015 000
and
4a0 905 810C is for cars 8B-S-000 001>>

Now to determine which is mine...

[UrS4boy]

European KATE tells me ignition switch 4A0 905 810B is for cars >>8B-R-015 000 and 4a0 905 810C is for cars 8B-S-000 001>>
Now to determine which is mine...

The correct PN for your ignition switch is 4A0905849B. The SA000001 switch is 4A0905849C. My good friend, Kate, in the parts depart says she has never heard of 4A0 905 810B or 810C. ("Not in stamm")

[UrS4boy]

Awesome guide by the way, will be of great help when I attack this issue So if the ignition switch is acting up it can cause these issues that I am having? I have also heard of an x-relay ? Great info and help as usual UrS4Boy!!

Your thread started off about the climate control but as soon as you started to mention other things that weren't powered, a little bell went off in my brain "Ignition switch!!". This is common on the C4 UrS cars so I presume it is similar on the B3 and B4s.

The "X"-relay is the load reduction relay that is triggered when you turn the ignition switch to start (it cuts all the power to the accessories, e.g. radio, headlights, climate control, etc) so the battery power is concentrated on energizing the starter. The PN is 357906381B and should be a 12V, 70 Amp relay. It is described as "relay for the relief relay x contact, relay location 5 (in the fuse box, as shown below) (Should be the 213 relay hiding in the shadows, right rear)

[k.alle]

The correct PN for your ignition switch is 4A0905849B. The SA000001 switch is 4A0905849C. My good friend, Kate, in the parts depart says she has never heard of 4A0 905 810B or 810C. ("Not in stamm")

Well she's a biatch when it comes to typing spelling part no for her, she wants them clogged together but presents them to me with fancy spaces and all

Your thread started off about the climate control but as soon as you started to mention other things that weren't powered, a little bell went off in my brain "Ignition switch!!". This is common on the C4 UrS cars so I presume it is similar on the B3 and B4s.

The "X"-relay is the load reduction relay that is triggered when you turn the ignition switch to start (it cuts all the power to the accessories, e.g. radio, headlights, climate control, etc) so the battery power is concentrated on energizing the starter. The PN is 357906381B and should be a 12V, 70 Amp relay. It is described as "relay for the relief relay x contact, relay location 5 (in the fuse box, as shown below) (Should be the 213 relay hiding in the shadows, right rear)

Well you are probably right, I hope so anyways. Can't stand this anymore, I hate intermittent problems that I can't find the source of..

So if changing ignition switch does not fully help perhaps I should investigate some in that x-relay then?

[UrS4boy]

..So if changing ignition switch does not fully help perhaps I should investigate some in that x-relay then?

*IF* you could find a good used J59 X-relay, aka "Relief Relay", e.g. borrow one from a friend, then you could try that right away. It is the 213 (in position 5 (to the right of the (Audi) logo in these relay maps)).

[k.alle]

Ignition switch is ordered from german ebay and should be with me beginning of next week.
Lets hope for the best.

[UrS4boy]

Ignition switch is ordered from german ebay and should be with me beginning of next week. Lets hope for the best.

Oops. I guess you didn't read the part in the DIY pdf about only buying ignition switches from the dealer (some of the aftermarket switches had a short time to failure record). Good luck.

[k.alle]

I did and it's a calculated risk, if this fixes the problem I happily will buy one genuine from VAG and change it again.
But as I don't know for sure yet I rather spend as little money as possible, the labour itself (doing it multiple times) is no issue.

[ManiacuV6]

If you use 3 short lenght wires you can put ingnition on and start the car . And all without the ignition switch. And you can know for sure if is a ignition failure.
IF the X relay is gone you cannot use the windscreen wipers.