Mercedes C180 2008 - Intermittent rear indicator failure

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Sun 15 Oct 2023 17:24
Mercedes C180 2008 - Intermittent rear indicator failure - AB1

I have a Mercedes C180 - 2008. The rear indicators and rear windscreen air-con randomly stop working. Sometimes whilst driving or as soon I start the engine. I turn the engine off, remove the key, leave it for a few seconds, restart the engine and everything works again. Has anyone else come across this problem and know what is the cause/solution?

Thank you.

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Sun 15 Oct 2023 18:14
Mercedes C180 2008 - Intermittent rear indicator failure - madf

Bad earth at rear.

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Sun 15 Oct 2023 18:27
Mercedes C180 2008 - Intermittent rear indicator failure - elekie&a/c doctor
All these functions are controlled by the rear “Sam “ ( signal acquisition module) . It’s located in the boot . I would check all the connections to it and make sure there’s no evidence of water ingress . Also check connectors at both rear light clusters . Inspect for any overheating on the terminal pins.
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Sun 15 Oct 2023 19:28
Mercedes C180 2008 - Intermittent rear indicator failure - AB1

Thanks for your reply. I will take a look and see if anything looks out of place. I'm no mechanic so I imagine I'll need to take it to a garage to get it looked at properly. Do you what price range this problem usually costs?

Thank you.

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Sun 15 Oct 2023 19:47
Mercedes C180 2008 - Intermittent rear indicator failure - AB1

Thank you for your reply. If this is the case is it usually an easy thing to diagnose? Is it also a costly repair?

Thank you.

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Sun 15 Oct 2023 20:13
Mercedes C180 2008 - Intermittent rear indicator failure - elekie&a/c doctor
I would get it looked at first . It may be a connector issue . If the Sam is faulty, they are about £300 . Plenty of s/hand units available.
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Sun 15 Oct 2023 21:22
Mercedes C180 2008 - Intermittent rear indicator failure - AB1

Okay. Thanks for your help and advice. Much appreciated.

Edited by AB1 on 15/10/2023 at 21:23

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