MK5 Golf GTI

All Things Mk5 => Mk5 General Area => Topic started by: Multicrazy on August 22, 2023, 07:22:53 pm

Title: No power to fuses in engine bay
Post by: Multicrazy on August 22, 2023, 07:22:53 pm

Hi all, I just wanted some guidance on how I can diagnose low voltage on fuses F6, F9, F10, F11, F12 (fuse box next to car battery) I am only getting 3.5v to these fuses and it’s throwing evap and fuel pressure regulator codes. I have tried giving those fuses direct from the battery and the codes go away. But how can I trace where these fuses get power from?

And also as a side note a few weeks back my ecu got fried and water got into it and the car wouldn’t start I had no check engine light. I’ve managed to get a donor ecu, with the cluster and keys as a set so the car starts good and even drives when giving direct power to those fuses. Could the Body Control Module have gone bad cause of the water and it might have short something in it as well? If someone can guide me where those fuses get power from that would be awesome!

Title: Re: No power to fuses in engine bay
Post by: pudding on September 01, 2023, 08:53:49 pm

Check the ground and main battery straps for corrosion.

How in the love of god did water get inside the ECU?  That is impossible unless someone has had it apart before and didn't reseal it properly afterwards.