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A5 B8.5 Engine Bay Fuse Box / Overheating issue

43 views 1 reply 2 participants last post by  Darklight  
#1 ·
I have recently had an overheating issue my car, it seems the Radiator fans aren't engaging when the engine gets hot. I've run through the line checking that the main fuses are all intacked and that power is at least going to the relay that is on the radator fan housing. I have also independly tested the fans, and those are working as well when directly hooked up to a 12v battery.

I have also had the backlight of the engine collant gauge go on-off-on a few times intermitently.

While testing fuses I noticed that this one is not receriving any power.
Fuse 9 in the Engine Bay Fuse box (SB) - Labeled as Voltage stablilizer / ECU was not receiving any power at all. I have pulled out the fuse and checked it, and even swapped it out. In the fuse slot there is metal prongs on both ends, but when testing with ground, even when the car is turned on, there is no voltage.

It is the (Orange 5) Fuse that is circled in yellow.
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Does anyone have any experience with what this fuse does, and if this is supposed to be receiving power, or if anyone has seen the backlight flickering on the Engine coolant temprature gauge, I would greatly appriciate any information.
 
#2 · (Edited)
Check the voltage stabilizer module if its working. Normally for the fans I would say check the temperature readout. Maybe its working properly but the temp sensor does not provide the right temps. I think these problems are unrelated to each other. Do you have Start/Stop on your car? Is it working?

Edit: After looking at some details to the electronics the Fuse you're mentioning is not so related to the Voltage stabilizer as it is for the ECU itself. Check the car for fault codes before doing anything in the fuse box. As for the fans i still think the temperature sensor could be damaged.