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I recently bought my second French car. Citroen C4 HB 2005 80KW 110HP 1.6hdi (i don't think engine specs matter for this specific matter, but still..)
The engine is in great condition, and luckily, I have a great mechanic near where I live. However, he's a mechanic after all, and all the electricians nearby are not so good with French cars.
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The window control unit on the driver's side is malfunctioning for the front windows. If I try to control the front passenger window from the controller unit, sometimes the driver's side is also affected. Controlling the driver side window works fine when going down. However, when I want to close it, it gets stuck and doesn't respond, only works after many attempts. This is the most important part because after parking my car I'm literally sweating to close my window before leaving the car which takes 1-2 minutes of trial error.
I thought it was about the controller itself and just replaced all of them with an aftermarket controller unit but the problem persists. So, I came to the conclusion that this not about the controller but the wiring itself.
What would be the best way to start troubleshooting this issue? Your help is much appreciated.
The reason I want to learn to fix this is because most of the old French cars are known for their electronic issues, but I still love them
, like a toxic relationship. And the electricians just ruin the wiring while trying to fix them, so I want to do it right on my own.Thanks in advance