Any DIY to replace Solar Censor on E70
 

Solar Sensor is behind the Rear view mirror. I was told that my Solar Sensor might be Bad and causing the AUX Cooling FAN to run all the time when AC is ON. Thats the FAN sitting behind the Radiator in the front of the Car.

part # 61359214977

The rear view mirror clam shell is held on by a few clips. It very easy to pry open and I was actually able to split it with my hand. But to be safe use a plastic trim tool and insert it right in the middle and give it a very gentle nudge and it will start to snap apart. I think the solar sensor is bonded to the windshield so you might need to take a razor blade to remove the harden glue. Just replace with new part. Please do a follow up write up once you have done this as I've only replace the Cond. sensor.

is that the big round on or the smaller one underneath?

its the Big round with metal clips on it.

OK.

Some instructions

- move your rear view mirror up and out of the way (as much as you can)
- split the windshield mount in two halfs (you can try a finger nail or a plastic panel removing tool)
- disconnect electrical connector from the sensor

this is where it gets deep. I would suggest you split the new sensor into two halfs. The glue and front part and electronics back half. You will notice how the two parts are connected. I would do this as I found it very difficult to pull my old sensor off the windshield. (In my case I used needle nose pliers and pulled a little at each time. It took me a good 10 minutes)

on the new sensor
- separate front from back of the senor

on mounted old sensor
- pull two metal tabs outwards (to release from windshield mount)
- using thin screwdriver separate two parts of the sensor leaving the glued part attached to the windshield
- align and snap the new electronics part to the window mounted half
- connect connector
- reinstall two half left and right side of the mirror post

IMPORTANT
- at no time do you want to exert outwards pressure on the windshield that is of great force. You make a spider web crack: you gonna have a bad day. :bustingup

Good luck and let me know in case I was not clear in my description.

So you left the glued part on the windshield and attach the electronic part to the old glued part correct. Does metal plates hold the sensor to the windshield or just the electronic part..

why you change your sensor and did you need to clear the codes later .. ??

Thanks for the info..

Do not remove the glued the part, it is just plastic piece. Just remove the electronic part and replace it with the new one. The part number you referred above is just the electronic part. If you want to remove the glued part, you have to replace the whole windshield, because it is almost impossible to re-attach the plastic piece back to the windshiled and you will damage the plastic piece when you are removing it. There is no replacement for the plastic piece, only the whole windshield.

like "rogerkiu" said; to remove the plastic half glued to the windshield, it will become damaged beyond use.
The two halfs.
Once you half the halfs separated you will notice that the one that attaches to the windshield is basically plastic with glue on one side (the glue is of a like solid silicone consistency)
The other half will have the electronics and metal clip attached to back of it.
When installing make sure the two plastic parts clip back together.
The metal clip will then hold clipped plastic assembly to the window mounted trim.
Make sure everything is aligned as you are installing things.

Wait.

Most AC systems will run that fan whenever the AC is on.

Dont go chasing after a solar sensor just becuase someone TOLD you.

Get a real DIAGNOSIS.

Correct!
Just to clarify that in a modern car the AC compressor and fan are controlled by the engine control unit.Ac compressors are variable displacement,not just ON/OFF.The fan speed and compressor load are requested by the AC control unit.The fan will be on only after pressure is built into the condenser,not just when the AC compressor is turned on.