Audi 100, '94. no heat

Hanuman · 08-11-14, 08:09 AM

Due to limited time available, I'm going straight for the 'cry for help', instead of delving in myself and crying only when I have a pile of unrecognisable bits.

So. 1994 Audi 100 2.8e Quattro.
Interior heater(climate control) is simply not outputting any heat.
Andy, from whom I bought the car, mentioned something back in the misty past, which is long forgot now.

Some pointers as to where to start, BTDTGTSTS, even a full how to would be appreciated.
In the meanwhile, I'm off to do some more diagnosis on the V8, weather permitting.

spink · 08-11-14, 08:37 AM

Climate control equipped?

Most likely the motor for the mainflap is buggered,or the plastic arm has snapped

Check codes on panel before you go any further

Hanuman · 08-11-14, 08:49 AM

Yes, climate equipped.

check codes?

spink · 08-11-14, 08:51 AM

You can get fault codes out of the panel.

My battery on phone is nearly out so just Google 'audi c4 climate codes'

Audi100C2 · 08-11-14, 09:01 AM

I think i can say congrats, you may have to change this:

Don't use anything but the original part (Hella Behr), or you may have to do it every year. The radiator on the pic above was the Audi original (!), which is the same as Hella as far as i know. Lasted 23 years, so it is not so bad.

Hanuman · 08-11-14, 09:41 AM

it's not leaking,thats for sure. the cooling system does lose a little water going out of the breather connection on the expansion tank. it's another small job, not done, on a car I didn't expect to keep this long.

spink · 08-11-14, 09:51 AM

http://forums.quattroworld.com/a6100/msgs/3334.phtml

http://www.s2forum.com/forum/showthread.php?t=64305

Hanuman · 08-11-14, 10:44 AM

I'm braving the elements emptying the jalopy. It's 'kin miserable down here.

So, I'll get to the diagnostics in a while. Nice that they have them incorporated in the display, rather than only on a handheld. The V8 uses the 2x2 OBD,and I've been too tight until now to get the ros-tech.

Cheers for the links

Hanuman · 08-11-14, 12:48 PM

Ah. Those codes.....lots of them. Seeming to back up the flap blocked/not moving situation.

The obvious anomalies are-

01c) 8.5/11.7/13.5
02c) 15.4
03c) 15.5

06c) 25.5 actual outside temp is around 12.0

There's a few values displayed which are outside of the table listed on Quattroworld; ie the suffix small digit being out of range, or the entire code not being available to look up. Eg. 01.0

msh · 08-11-14, 01:17 PM

02, 03, 06 channels - these are DIGITAL values of those temp sensors - I don't know what exactly it is, because I don't have need to know that, in any case when I want to check how temp sensors are working, I'm looking to channels 56-60, because there are numeric values in celsius or fahrenheit, depending on control unit coding.

Could you explain your last sentence a bit more throughly?

As for faults, 8.5 is the most important, but also easiest to fix. Temp flap motor is located under windscreen in engine compartment, to access it requires removal of decorative cover, and small plastic cover with some phillips head bolts, three more for that motor + disconnect connector and link. To open motor, three or four bolts has to be undone, either phillips head or torx, the gears that comes out, removed, everything greased and afterwards motor tested by applying some voltage to it, only problem - the motor is 7v, not 12v.

11.7 is currently nonexistant error - sporadic means that since last time errors was erased control unit has found that fault but it has disappeared - but that hella made control unit has very good fault memory, you can buy in junkyard control unit that has spent good time in shelf and it still will have faults from previous car. And 13.5 is stuck footwell/defroster flap motor, accessing it requires center console removal.

I would also recommend you to check valve that closes coolant flow through heater matrix - it is located next to heater unit in engine compartment - I've heard that it can fail in closed position - although in your case stuck temp flap could be enough, so you can just check both hoses without removing that cover, with engine warm, to see if both hoses are hot or just one.

08-11-14, 08:49 AM	#3
Hanuman Trickster Classic Audi Club Member Join Date: May 2009 Location: Heckling from the cheap seats, Phnom Penh, KoW Posts: 7,006	Yes, climate equipped. check codes? __________________ I wish they would keep the damned Chinese away now that I can go home, so that I can enjoy Fish amok and a draught Angkor

08-11-14, 09:41 AM	#6
Hanuman Trickster Classic Audi Club Member Join Date: May 2009 Location: Heckling from the cheap seats, Phnom Penh, KoW Posts: 7,006	it's not leaking,thats for sure. the cooling system does lose a little water going out of the breather connection on the expansion tank. it's another small job, not done, on a car I didn't expect to keep this long. __________________ I wish they would keep the damned Chinese away now that I can go home, so that I can enjoy Fish amok and a draught Angkor

08-11-14, 10:44 AM	#8
Hanuman Trickster Classic Audi Club Member Join Date: May 2009 Location: Heckling from the cheap seats, Phnom Penh, KoW Posts: 7,006	I'm braving the elements emptying the jalopy. It's 'kin miserable down here. So, I'll get to the diagnostics in a while. Nice that they have them incorporated in the display, rather than only on a handheld. The V8 uses the 2x2 OBD,and I've been too tight until now to get the ros-tech. Cheers for the links __________________ I wish they would keep the damned Chinese away now that I can go home, so that I can enjoy Fish amok and a draught Angkor

08-11-14, 12:48 PM	#9
Hanuman Trickster Classic Audi Club Member Join Date: May 2009 Location: Heckling from the cheap seats, Phnom Penh, KoW Posts: 7,006	Ah. Those codes.....lots of them. Seeming to back up the flap blocked/not moving situation. The obvious anomalies are- 01c) 8.5/11.7/13.5 02c) 15.4 03c) 15.5 06c) 25.5 actual outside temp is around 12.0 There's a few values displayed which are outside of the table listed on Quattroworld; ie the suffix small digit being out of range, or the entire code not being available to look up. Eg. 01.0 __________________ I wish they would keep the damned Chinese away now that I can go home, so that I can enjoy Fish amok and a draught Angkor

08-11-14, 08:37 AM	#2
spink Senior Member Classic Audi Club Member Join Date: Dec 2007 Location: yorkshire Posts: 1,525	Climate control equipped? Most likely the motor for the mainflap is buggered,or the plastic arm has snapped Check codes on panel before you go any further

08-11-14, 08:51 AM	#4
spink Senior Member Classic Audi Club Member Join Date: Dec 2007 Location: yorkshire Posts: 1,525	You can get fault codes out of the panel. My battery on phone is nearly out so just Google 'audi c4 climate codes'

08-11-14, 09:01 AM	#5
Audi100C2 Grown up member Join Date: Dec 2009 Location: Estonia Posts: 194	I think i can say congrats, you may have to change this: Don't use anything but the original part (Hella Behr), or you may have to do it every year. The radiator on the pic above was the Audi original (!), which is the same as Hella as far as i know. Lasted 23 years, so it is not so bad.

08-11-14, 09:51 AM	#7
spink Senior Member Classic Audi Club Member Join Date: Dec 2007 Location: yorkshire Posts: 1,525	http://forums.quattroworld.com/a6100/msgs/3334.phtml http://www.s2forum.com/forum/showthread.php?t=64305

08-11-14, 01:17 PM	#10
msh 4 ring whore! Join Date: Jun 2008 Location: Rucava, Latvija Posts: 3,816	02, 03, 06 channels - these are DIGITAL values of those temp sensors - I don't know what exactly it is, because I don't have need to know that, in any case when I want to check how temp sensors are working, I'm looking to channels 56-60, because there are numeric values in celsius or fahrenheit, depending on control unit coding. Could you explain your last sentence a bit more throughly? As for faults, 8.5 is the most important, but also easiest to fix. Temp flap motor is located under windscreen in engine compartment, to access it requires removal of decorative cover, and small plastic cover with some phillips head bolts, three more for that motor + disconnect connector and link. To open motor, three or four bolts has to be undone, either phillips head or torx, the gears that comes out, removed, everything greased and afterwards motor tested by applying some voltage to it, only problem - the motor is 7v, not 12v. 11.7 is currently nonexistant error - sporadic means that since last time errors was erased control unit has found that fault but it has disappeared - but that hella made control unit has very good fault memory, you can buy in junkyard control unit that has spent good time in shelf and it still will have faults from previous car. And 13.5 is stuck footwell/defroster flap motor, accessing it requires center console removal. I would also recommend you to check valve that closes coolant flow through heater matrix - it is located next to heater unit in engine compartment - I've heard that it can fail in closed position - although in your case stuck temp flap could be enough, so you can just check both hoses without removing that cover, with engine warm, to see if both hoses are hot or just one.