G42 Sensor Location

Hello,

I have a 2012 Seat Alhambra 1.9tdi Ecomotive SE (177hp/130kw). It is the engine with the plastic intake manifold as fitted to some Audi’s and Seat’s if that helps.

It went into limp-mode yesterday with the DPF light up. I have a Ross-Tech VCDS and found 2 error codes. High soot level and this sensor failure.

„Intake Air Temp. Sensor (G42) P0112 00 [175] - Signal too Low“

The intake air sensor fault is stopping me doing a forced DPF regeneration. Although I’m an ex-automotive engineer and a good mechanic I’m really having difficulty in actually actually locating this sensor, even looking at ETKA doesn’t help. Does anyone with a workshop manual or with access to the full Seat workshop software tell me where the sensor is located and how to get to it.

Any advice gratefully accepted.

Regards

Michael Dolan

#1

Hi,

G42 seems to be a misleading information.
I would assume that a G42 is not present on modern engines like yours. See its usage e.g. here :click:

I believe that in your case P0112 refers to the intake air temperature sensor which I expect is integrated in the air mass sensor (LMM) housing.
Any change in the error message if you unplug the LMM?

PS: In this case of a gasoline engine it is on the intake manifold, see www.sgaf.de/content/code-p0112-432938

#2

Thank you, I will have a look tonight. I spent many hours looking for a separate temperature sensor and did not consider that it may be part of the MAF sensor. One problem with believing that VCDS is 100% correct.

#3

@armstrongracer: We are always happy to help.
for the old model the temperature sensor was combined with the intake pressure sensor. I may be also advisable to take a look in that direction.
OT: I am very pleased to learn that there are Sharalhambras cruising around in the US. Did you purchase it locally or did you import the vehicle?

Have a great day :slight_smile:

#4

Und ich dachte immer Dublin/Irland wäre Europa :-/

#5

#4: OK. Habe das Profil nicht gelesen.
Der Zugriff kam aus den USA…

#6

Hello Heisenberg, I’m actually from Dublin, Ireland but when I logon from work the server will be from USA.

The reason I’m having difficulty is because I’m not sure if it is a separate inlet pressure sensor/temperature sensor or part of the MAF sensor as mentioned by Urborka. When I google IAT sensor for my model of Alhambra on some of the good German part sites I get a combination pressure sensor with temperature output. I had something similar on a Saab TTID and that was located directly into the inlet manifold. My model of Alhambra has that plastic inlet manifold and the only thing I can find attached to that are the vacuum solenoids. The only other location I can think of for that pressure/temperature switch if it exists is in the pipework between the turbo and inlet manifold and a lot of that is hidden either behind the engine or under it. Engine bay of Alhambra is incredibly tight. I really need a diagram for a CFGC engine.

#7

Dear armstrongracer,

Now I read your profile :lol:
Thanks for the clarification.

You can find all the parts and a drawing here: volkswagen.7zap.com/de/rdw/sharan+syncro+4motion/sha/2012-689/

It’s in german, but with the drawings it should not cause too much trouble…

#8

volkswagen.7zap.com/en/rdw/sharan+syncro+4motion/sha/2012-689/

en = english :wink:

#9

Thank you James that was really useful. I actually have good technical German but speak really badly. I spent many months near Chemnitz putting in a robot line to assemble Siemens Piezo Injectors.

I think I found the sensor, it looks like a MAP/Temperature sensor in the pipe to the intercooler. Could be difficult to reach though, may have to go from underneath the vehicle.

#10

www.vaglinks.com/vaglinks_com/Docs/SSP/VWUSA.COM_SSP_826803_2.0L_TDI.pdf page 50

does this fit the CFGC (EA189) engine?

#11

der g42 Sensor ist ein kombinierter Sensor der auch für den Ladedruck zuständig ist.
Er sitzt hinter dem Ladeluftkühler (Beifahrerseite) im Luftkanal welcher zum Motor hin geht.

Das Teil ist hier mit Nummer 16 eingetragen:
volkswagen.7zap.com/de/rdw/sharan+syncro+4motion/sha/2012-689/1/145-145090/

Teilenummer: 03G 906 051 E