Sensors location - Climate Control

[goldy1234]

yo,

My car: Audi a3 1.8t 8l 1998 AGU
I've been playing around with climate contol:
AudiWorld Tech Articles

And I'm interested in physical location of sensors on blocks:
49 - Malfunction counter for speedometer (vehicle speed) signal
51 - Engine Coolant Temperature (ECT) in deg C
56 - Temperature in deg C, from Interior Temperature Sensor, in Headliner (G 86)

On block 49 I get similar temretature as block 51, does anybody know what means?

tnx for you help

 

[bengal]

Iv finally figured this out for myself recently option 49 is the coolant temperature and 51 is the oil temperature i have an agu also. I dont know about option 56 tbh. The coolant temp sensor is on a pipe between the airbox and the engine im not sure on the oil sensor it will be around the sump area i would think but iv never had to pay attention to it.

 

[goldy1234]

Iv finally figured this out for myself recently option 49 is the coolant temperature and 51 is the oil temperature i have an agu also. I dont know about option 56 tbh. The coolant temp sensor is on a pipe between the airbox and the engine im not sure on the oil sensor it will be around the sump area i would think but iv never had to pay attention to it.

I think you mean that 49 is oil temperature and 51 is colant temperature (because 49 is warming up slower)
hmm, about block 49; I'm not so sure that's the oil temerature, because the temperature never drops below 30°C (even ouside temerature is -10°C), or it's possible that sensor has minimal limit temp 30°C.

I also compare block 51 (colant temerature) and default analog gauge for colant temperature, and on block 51 temperature raises quicker than on analog...why the delay? Is it possible that there are two sensors for colant temperature?

 

[bengal]

No on mine its 100% 49 for coolant and 51 im guessing is oil temp which will warm up faster i cant see what else it would be also this gets to 90 when my needle reads 70ish. As for the needle it isnt that accurate my needle shows 90 when the temp on the climate says 85 ish but the operating temp of the coolant is between this and just over 90 but the needle stays at 90. Iv never checked what temp they are at at start up so i cant help you there. Check option 49s reading with the coolant temp reading on vag com it will be the same.

 

[goldy1234]

I'll measure temperature with IR thermometer while the car will be warming up and report it here.
What's the block on VAG that I can see the colant temperature?

 

[bengal]

I cant remember exactly its been a while since iv checked but heres a link to the vag com measuring blocks http://www.ross-tech.com/vag-com/m_blocks/

 

[goldy1234]

one more example when the cabine is already warmed:

sensor on block 56 has temp: 17°C
sensor on block 57 has temp: 27°C
-----------------------------------------
average temp of sensors : (17°C + 27°C) / 2 = 22°C
desired temp on climate control: 23°C

Why is the temp on sensor 56 so low? Is sensor in bad condition? Where is that sensor?
Begal could you check temp on block 56 in your car, is it also so low?

 

[bengal]

one more example when the cabine is already warmed:

sensor on block 56 has temp: 17°C
sensor on block 57 has temp: 27°C
-----------------------------------------
average temp of sensors : (17°C + 27°C) / 2 = 22°C
desired temp on climate control: 23°C

Why is the temp on sensor 56 so low? Is sensor in bad condition? Where is that sensor?
Begal could you check temp on block 56 in your car, is it also so low?

I checked mine today and it is below what the climate control says but it will be as it will take a long time for the inside of the car to get up to the correct temperature its been -10 and below here also. When the door is opened or the window the temperature drops down so its the correct sensor for the climate control. I think its right above the climate control unit where there is a rectangle shape of small holes. Thats the best i can explain what it looks like and i cant think of anywhere else it will be.

 

[goldy1234]

I checked mine today and it is below what the climate control says but it will be as it will take a long time for the inside of the car to get up to the correct temperature its been -10 and below here also. When the door is opened or the window the temperature drops down so its the correct sensor for the climate control. I think its right above the climate control unit where there is a rectangle shape of small holes. Thats the best i can explain what it looks like and i cant think of anywhere else it will be.

sensor on block 57 react very quickly as you described, but what is your temp on sensor (block 56), does it ever go over 17°C?

 

[goldy1234]

i found something interesting: (not for model audi a3)

1 - Kick down switch
Not installed on all vehicles
Disengages A/C compressorCan also be controlled by Transmission Control Module (TCM) or Engine Control Module (ECM)
2 - Connector station
3 - Footwell/defroster flap motor -V85-
With position sensor -G114-
4 - A/C control head -E87-
5 - Fresh air blower -V2-
6 - Control module for fresh air blower -J126-
7 - Interior temperature sensor fan -V42-
8 - Instrument panel interior temperature sensor -G56-
9 - Outside air temperature display -G106-
Not installed on all vehicles
10 - Temperature regulator flap motor -V68-
With temperature regulator flap motor position sensor -G92-

11 - Central air flap motor -V70-
With central flap motor position sensor -G112-
12 - A/C refrigerant low pressure switch -F73-
13 - Evaporator housing and heater box
14 - Fresh air intake duct temperature sensor -G89-
15 - Fresh air/recirculating flap vacuum motor
16 - Fresh air/recirculating flap two-way valve
17 - Headliner interior temperature sensor -G86-