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Instrument cluster going nuts after turning off car

1534 Views 14 Replies 7 Participants Last post by  PDXsmart
Ok... so we bought a used 2008 yesterday and when we got home we noticed that the instrument cluster was making that reset noise that it usually only does when you unplug and then plug it back in. So I reseated the connector to be sure it was in there correctly and it still did it.... for 4-5 minutes before I took it out of the car. Any ideas? Maybe a ground short somewhere?
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How old, is the battery in your car?
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That may be it as well.... haven't checked the levels yet... it was midnight getting home and work today. Possibly original to the car... it has 79000 on it. Great condition though.
That may be it as well.... haven't checked the levels yet... it was midnight getting home and work today. Possibly original to the car... it has 79000 on it. Great condition though.
The dash lights... including the radio and button bank were flickering as well.... will check the battery once home.
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Modern cars, need a strong battery to operate on correctly.
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Hard agree with smark, there. I accidentally let the battery die in the 2008 I bought last fall. When I jumped it a few days ago the cluster was going haywire just like yours. I pulled a new battery down from my battery wall and all is well. :)
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It appears it was in fact the battery...new one installed and all is well.... thanks!!
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...don’t know what’s scarier....that the cluster went nuts or that Miss Mercedes has a battery wall...

jetfuel....?????
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...don’t know what’s scarier....that the cluster went nuts or that Miss Mercedes has a battery wall...

jetfuel....?????
I'll have to get a picture, but it's a wall with five or so batteries of different flavors. Three diesel batteries and two that would work in a smart. :ROFLMAO:

I recently discovered that a desulfator can bring dead batteries back to life, so now I have more batteries than cars to put them in. I've also removed the batteries out of a couple of vehicles because the local junkies that moved in nearby like to steal cars. Ugh.

Hopefully the extra batts will come into use with my school bus project!

Either way, it's definitely time to move far from the city.. :)
OK so the saga continues… The sound it’s making is the solenoid‘s resetting much like when you unplug and replug the cable into the back of it. Only it does it for an extended period of time. So I went down to my local secondhand auto parts place and picked up a 451 speedo cluster and swapped out and stop doing it… but the new cluster is showing an airbag light and intermittently both of them are throwing an engine code which I haven’t been able to check yet because I ran out of time today. I know I’ve been out of the game for a couple of years… Is anyone figure out how to reset an airbag light without going to a Mercedes dealer yet? Also it doesn’t show up the odometer unless the car is in park which is really weird…. The new speedo that is.
Have you tested the battery voltage with a multimeter? Test it both with the car running (if it will start) and with it off. You should get something above 12v off and 14v when running. If it's not any higher when running than when off, your charging circuit may have a problem, possibly the alternator. The voltage you get off should help diagnose where to go if the charging circuit is working.
Well it was definitely the speedometer set up. I swapped out the speedometer and it’s not making that noise anymore. Now I’ve got an issue where the airbag light is on and the odometer is not showing unless the car is in the opposition or the accessories position… weird. It’s not throwing any engine codes anymore either.
Just for grins & giggles - with everything plugged in (best speedo) and ready to "play" disconnect the battery for a half hour or so as things may reset with a new awakening....

Wash, rinse, repeat? 😱

Oh, and a long shot - recently had a visit by "Murphy" and the infamous 3 bars issue when I alternated key FOBs. Found that the alternate (less used) had a weak battery. Replaced and life is good!
I don't know if this matters or not. My car is a May 2009 delivery. I have replaced the fob batteries twice since the originals. I don't drive my car a lot, but I make sure to rotate the fobs with each drive. So far, I have gotten about four and a half years from a set of fob batteries.
I don't think it's an issue.... the FOB seem's strong so far. What it may be tied to is one of the tail lights burnt out or broke this afternoon.... of course I'm getting the hyper flash on that side but I wonder if that's part of it as well. I have a feeling this is a smaller issue rather than a larger one.
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