[Ceric]

MICS-5132 has been superseded by a newer technology MICS-4514, that is why you can not find 5132 anywhere anymore.

 

[Alex323Ci]

^ ah dang, it looks like they sell that one for $10 but it's a totally different shape and doesn't appear to have prongs either. :banghead:

wonder how hard it would be to retrofit (if even possible?)

 

[edber]

I recently got an auc error in diagnostics and upon reading this thread I decided to buy just the sensor.
The sensor cost just 8 euros from china and I just put it in place,not knowing wether or not the pins were in the correct order,but auc error is gone
and I can hear the heater box closing the flaps when there is fumes,so a cheap fix,compared to buying the full auc sensor for stupid money.

 

[Alex323Ci]

I recently got an auc error in diagnostics and upon reading this thread I decided to buy just the sensor.
The sensor cost just 8 euros from china and I just put it in place,not knowing wether or not the pins were in the correct order,but auc error is gone
and I can hear the heater box closing the flaps when there is fumes,so a cheap fix,compared to buying the full auc sensor for stupid money.

yep well some of us have the newer version sensor and have to spend stupid money to replace

but fault code is gone and it now works like it did when new :thumbup:

 

[emeni09]

I would not bother. by the time the sensor reacts all the fumes are already in the car. it would only make sense in a long tunnel. but paying bmw prices for such a small sensor does not make sense

 

[edber]

I like to have no errors in diagnostics and I cant see how the newer sensor can be HUGE money??
Sensor reacts quickly enough in my opinion.

 

[hgrunt]

yep well some of us have the newer version sensor and have to spend stupid money to replace

but fault code is gone and it now works like it did when new :thumbup:

Theoretically, the old and new sensors put out the same signals, and should work the same if the plug is the same. I wonder if it would work just as well if you plugged a box with a fresh old sensor, vs the newer one.

 

[hgrunt]

I would not bother. by the time the sensor reacts all the fumes are already in the car. it would only make sense in a long tunnel. but paying bmw prices for such a small sensor does not make sense

It reacts at least as fast as I do! Mine was active frequently, and I loved it once it was working properly.

In my case, I was able to buy the Figaro sensor that sits inside the AUC box for $10. If I had to buy the whole unit for $50 I wouldn't have bothered either.

 

[SoCalZman]

It reacts at least as fast as I do! Mine was active frequently, and I loved it once it was working properly.

In my case, I was able to buy the Figaro sensor that sits inside the AUC box for $10. If I had to buy the whole unit for $50 I wouldn't have bothered either.

How can you even tell its working? I leave my system on Auto and I cant ever tell if the outer doors close.

 

[Ceric]

First off, when you scan your car for codes with a BMW specific scanner, do you get the AUC Heating error message?

 

[edber]

How can you even tell its working? I leave my system on Auto and I cant ever tell if the outer doors close.

You can tell when you are close behind another vehicle(at traffic lights) and you will hear the change in airflow when the flaps are closing.
Mine reacts fast enough anyway.Best ***8364;8 I spent,compared to buying the full auc thingy.

 

[edber]

Now I need to install my solar sensor and get rid of that error on diagnostics.

 

[vasya]

Change this sensor today (buy from Aliexpress), picture:

will check...

 

[emeni09]

well, my sensor is gone again ) not going to pay 10$ to change it again. it was kind of useless, since the reaction time is very slow and also I've never seen the unit turning the recycling on when cooling /heating.
will add a new filter to see if that might fix it. otherwise good bye auc sensor

 

[hitbyastick]

well, my sensor is gone again ) not going to pay 10$ to change it again. it was kind of useless, since the reaction time is very slow and also I've never seen the unit turning the recycling on when cooling /heating.
will add a new filter to see if that might fix it. otherwise good bye auc sensor

Just curious, but how is your sensor 'gone again'? Did someone steal it? Did it fall out? How??? Did it de-materialize somehow through interaction with cosmic antimatter? Did it fall into a black hole?

I find it difficult to believe, that given where the sensor is located, inside a little black box clipped to the radiator fan shroud, that it could just fall out on its own.

 

[emeni09]

ups, what I meant is that the figaro is broken again, or at least I have a problem with it when I scan with inpa

 

[vasya]

ups, what I meant is that the figaro is broken again, or at least I have a problem with it when I scan with inpa

same problem:evil: , inpa say - auc sensor dead again...
may be sensor have frigging qulity...

 

[emeni09]

I'll leave it like that. For me it was too slow to switching to recirculation and when it did, it could only do it for heavy car fumes...

 

[tobiasmo]

Hi,

First off apologies and I have to correct myself from my last post from #41. I gave Pin 1 for the TGS 822 as being next to the hole in the case. I have removed the photo as I have been able to give a thorough test and have confirmed that is it incorrect. I don't have a lot of time to work on my car these days so this has taken awhile for me to check this.

I have also had the same issue again with my sensor, open circuit error on AUC Sensor. I ordered another sensor and have been able to test and work out the correct position is:
The Pin 1 of the TGS 822 sensor is located AWAY from the hole in the case.

I have just been on my first drive with it and it seems to work quite well, didn't really smell any fumes at all. I have just checked with DIS again and is all clear - no errors. Will be checking over the week though.

Someone also asked how do you tell where Pin 1 on the sensor is. There should be a tiny number next to Pin 1. On my last sensor it was the number 1 and this new one it is number 2. I marked it with a Sharpie. You may also want to use pliers to make sure it goes in the correct way. Also again no need to glue this down, just give a firm press. When in ignition 2 will warm up over the 90 seconds and you just need to test if it's warm.

Here is the Pin mapping:
From Car to TGS 822 Sensor
Pin 1 GND -> Pin 5
Pin 2 Resistance/Reading -> Pin 6
Pin 3 Circuit Voltage +2.5V -> Pin 1
Pin 4 Heater Voltage +5V -> Pin 2

Note: the sensor also has 2 other pins that are just there as a second circuit voltage pin 3 and a second Resistance pin 4 and not required.

Here is an excerpt from the original spec sheet showing you can use either Pin 1 or 3 and Pin 4 or 6. Note it needs voltage for heater VH and Circuit VC:

and here is a circuit I found that shone some light on how it is wired up:

It seems if the sensor is installed incorrectly it does work for a while (warms up like it should) but then must burn out which is why I and a few other people on here have had it eventually fail.

For people with the newer MiCS-5132 I have not had personal experience with but as someone else on here mentioned you will still have the same Pinouts from the car as the module is a direct replacement for the older AUC sensor so you could buy a second hand sensor box off ebay and then replace the TGS 822 sensor yourself to make sure you had a working sensor.

Btw it seems that MICS-4514 is not a direct replacement for MICS-5132 as they look very different from the pics.

Also if you google "MiCS-5132" with quotes you will find the Korean sellers for this part which may help anyone instead of buying a complete new sensor box. It seems you may have the same problem installing it into the correct position though as it has 4 pins that could be installed in number of ways into the box.

Tested like this first with no errors. Then installed into the box.

 

[Knight]

Am I understanding the following correctly:

1. If there is no AUC Sensor error, replacing the media with the fish tank filter is acceptable.
2. If there is an AUC Sensor error, then the options are replacing that Figaro bit or the entire sensor.

Side question:

What are the symptoms of a malfunctioning/dead AUC Sensor?