theunit

<center><img src="http://www.archicad.ca/wp/wp-content/photos/lmp.gif"></center><p>Ok here is a little background on what happened to make the Audi electrical system turn on me and hate me.

I was installing a escort radar detector hardwire install when all of a sudden I dropped my test light. It arced off the fuse panel and wouldn't you know it happened to fall on the fuse labeled "Turn Signals Flasher Unit".

So I frantically pull everything apart and pull every fuse to see if any have popped. To my surprise NONE of the fuses popped, not even the one where the wire got slightly singed. I repaired the wire to the fuse and put everything back together. Being extra careful to make sure everything was grounded correctly.

I then turn the car on only to find that my HVAC system no longer blows any air, it still illuminates but that is it. The fan will not come on.
The turn signals, don't work. The hazards do work. I am assuming at least I have broken the turn signal relay although I will have to do some testing to confirm.
The other thing that also has occurred is that it says it is -56 degrees outside. So I am assuming I fried the ambient sensor or at least a fuse.
I should also remark that my radio works fine even though it also seems to have taken the same fate of many of the others according to the VAG output.


I have VAG output (below) and any and all help would be greatly appreciated.

I throw myself on the mercy of the AW and beg for your help to get the A6 up and running again.

VAG-COM Version: Release 704.1
Data version: 20071016

Sunday,03,February,2008,09:12:18:59167

Chassis Type: 4B - Audi A6 C5
Scan: 01 02 03 06 08 15 16 17 18 34 35 36 37 45 55 56 57 65 67 75
76 77

VIN: WAUED64B01*******
------------------------------------------------Address 06: Seat Mem. Pass Labels: None
Part No: 4B0 959 760 C
Component: Sitzmemory R1 BF 0102
Coding: 00003
Shop #: WSC 00000

1 Fault Found:
00668 - Supply Voltage Terminal 30
07-00 - Signal too Low

------------------------------------------------Address 08: Auto HVAC Labels: 4B0-820-043-MY1.LBL
Part No: 4B0 820 043 AH
Component: A6-Klimavollautomat D65
Coding: 00160
Shop #: WSC 02325

8 Faults Found:
00779 - Outside Air Temp Sensor (G17)
30-10 - Open or Short to Plus - Intermittent
00756 - Left Vent Temp Sensor (G150)
30-00 - Open or Short to Plus
00757 - Right Vent Temp Sensor (G151)
30-00 - Open or Short to Plus
01809 - Actuating Motor for Temperature Flap; Left (V158)
41-00 - Blocked or No Voltage
01810 - Actuating Motor for Temperature Flap; Right (V159)
41-00 - Blocked or No Voltage
01274 - Air Flow Flap Positioning Motor (V71)
41-00 - Blocked or No Voltage
01297 - Sensor for Vent Temperature; Footwell (G192)
30-00 - Open or Short to Plus
01582 - Signal for Coolant Temperature
30-00 - Open or Short to Plus

------------------------------------------------
Address 17: Instruments Labels: 4B0-920-xxx-17.LBL
Part No: 4B0 920 981 G
Component: C5-KOMBIINSTR. VDO D12
Coding: 02264
Shop #: WSC 01013
WAUED64B01******* AUZ7Z0A1779676

1 Fault Found:
00667 - Ambient Temperature Signal
30-10 - Open or Short to Plus - Intermittent

------------------------------------------------Address 56: Radio Labels: None
Part No: 4B0 035 195 A
Component: Radio D00
Coding: 00201
Shop #: WSC 00003

1 Fault Found:
00856 - Radio Antenna
29-10 - Short to Ground - Intermittent

End ------------------------------------------

tozoM8

Then check for codes again.

theunit

I would do that although I don't have the radio code. I would then have to pay $42.50 at the local "friendly" dealership in order for them to pull my code. If there was anyway of getting around pulling the battery I would rather do that.

Of course looking back I should have pulled the battery as I ALWAYS do on my other cars when I do electrical work, that $42.50 may come back to haunt me

theunit

<center><img src="http://img.photobucket.com/albums/v739/hliu55/DVD/DVD53.jpg"></center><p>While searching for more any possible answers it also looks like I have another issue.

I ran across BD post on how the yellow "75X" is a switched power source. This does not seem to be the case on my A6 anymore.

Does anyone else know what this could mean?

squidix9

It is derived from circuit 30 through the load reduction relay. Do you have headlights?

Without X you don't have pwer to the HVAC head unit and it(HVAC control unit) is common to all the sensors and flaps. It supplies circuit 112 to all those components.

Start with the load reduction relay.

These circuit descriptions are based on a '99 but should be more or less generic for all C5's at least. And common at least in function for all A6's.

theunit

I do currently have headlights. I figured these would be gone if the X circuit went?

squidix9

But I would have thought so too. Circuit X powers most of the control modules and I would have thought the headlight control module too.

Edd W

that dead X circuit to find where it is fead from.

Boston Driver

...there is no excuse for working on electrical stuff without first disconnecting the battery. It takes all of a couple of minutes, and can save hours of headache...or worse....

thxguy

Go and get the code- I must have used mine at least twice now- Always good to have it.
Sorry I don't have any help for you- but I agree that there may be an in-line fuse above somewhere-

Good luck- let us know how it turns out- sorry for the 'turn' pun...