Outside Temperature Sensor VW Passat Audi Skoda - change without removing bumper + troubleshooting ✅

Описание: How to change VAG group outside/ambient air temperature sensor.
For most cars you can do this through the grille with long nose pliers, and don't need to take the entire front bumper off. Just use the pliers to push the 3 prongs in, and the sensor can be pushed back through the mounting hole, then pulled through the grille with hands or long nose pliers (depending on style of grille and room).
There is plenty of slack on the wire to bring it through the grille, and the sensor is just on a simple harness clip...although mine was a tad initially stiff and required some gentle persuasion.

My car's symptoms were wild fluctuations in the instrument cluster temp (e.g. saying it was -42c when it was actually 3c) for about 3 weeks, before completely failing to give any temp reading on the dash and resulting in an engine warning light.
If you have a climatronic unit then this requires the outside air temp sensor to work properly in order to function.

In my case a genuine sensor did not fix the problem (part #: 8Z0 820 535) which is used on most VW/Audi/Seat/Skoda between around 2004 and 2015 (please check your model though). So I traced the wiring from the sensor and back to the next harness which in the Passat B6 and B7 is just behind the radiator on the left hand side as you look at the engine from the front/adjacent to the headlight. My wiring was in contact with the top of the air conditioning condenser, rubbing and causing exposed copper wiring which was shorting out on the AC condenser metal- caused by sloppy workmanship by the AC company who changed my AC condenser about 5 months prior... who didn't route the cabling back in properly.

You could use a multimeter to check continuity between the two harnesses but the cause was obvious after a visual inspection in my case.

I own both OBD11 and VCDS; OBD11 threw up the code P007300, which would clear but came back pretty quickly after a couple of ignition cycles.

After I had cut out the two corroded wire sections and resoldered/shrink-wrapped them, my old temp sensor was working perfectly again.
So a quick visual check of the wiring from sensor to the next harness behind radiator is worth doing before ordering a new sensor- this would have saved me £37.

Example in the video is a 2012 Passat Alltrack, but many VAG cars of this era (2004-2015) use the exact same part number.

Hope this helps someone.