# Random alarms pop up and disappear

**URL:** <https://community.cartalk.com/t/random-alarms-pop-up-and-disappear/167459>\
**Category:** Maintenance/Repairs\
**Tags:** c-class, mercedes-benz\
**Created:** [July 17, 2020, 8:33am UTC](https://community.cartalk.com/t/random-alarms-pop-up-and-disappear/167459 "2020-07-17T08:33:41Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![Michael-393](https://avatars.discourse-cdn.com/v4/letter/m/9e8a1a/32.png) [@Michael-393](https://community.cartalk.com/u/Michael-393)\
**Post date:** [July 17, 2020, 8:33am UTC](https://community.cartalk.com/t/random-alarms-pop-up-and-disappear/167459/1 "2020-07-17T08:33:41Z")

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I have a C180 Mercedes benze 2013 model , for the past 4 months i experience random alarms on the dashboard ( hand break engaged, esp not activated and ABS off ) this alarms only pop up in the morning as soon as i start driving . I took it to the workshop to diagnose but they picked up nothing , but they suggested i replace the battery which i did but no change , took it back and they said i must replace the alternator , i serviced it and replaced voltage regulator , tested it and it was giving out 14.9 amps which is perfect but still the problem continues . I am stuck and really dont know what to look at anymore . This problem only occurs in the morning or when the car stand for a whole day , they will pop up for a few seconds and thats it they dont appear again until the next day . Please help with any ideas .

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**Author:** ![circuitsmith](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/circuitsmith/32/40376_2.png) [@circuitsmith](https://community.cartalk.com/u/circuitsmith)\
**Post date:** [July 17, 2020, 12:16pm UTC](https://community.cartalk.com/t/random-alarms-pop-up-and-disappear/167459/2 "2020-07-17T12:16:15Z")

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I think this vintage Merc. has wiring harnesses made with bio-degradable insulation.  
That stuff has a rather short lifetime and breaks down.  
Needless to say, harness replacement is a pricey job.

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**Author:** ![Michael-393](https://avatars.discourse-cdn.com/v4/letter/m/9e8a1a/32.png) [@Michael-393](https://community.cartalk.com/u/Michael-393)\
**Post date:** [July 21, 2020, 8:08am UTC](https://community.cartalk.com/t/random-alarms-pop-up-and-disappear/167459/3 "2020-07-21T08:08:59Z")

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Would they not pick that up when they diagnose the car ?