2009 C300 No Start after disconnecting and reconnection pyro-fuse connector near batt
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Joined: Oct 2009
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1986 porsche 928 1997 sl 600
2009 C300 No Start after disconnecting and reconnection pyro-fuse connector near batt
Hi Guys, So I had the day off from work and figured I would try to make my car better lol. I have an airbag light on since I purchased it and ran the code today on my scanner and have code 9CFF(Squib for pyrofuse "on-board electrical network line" has excessively low resistance. Next I searched around and found the connector to be the round yellow connector on the electrical box near the battery. The little brown safety tab is missing from mine and do not know if this affects anything? It came out fairly easily without nothing breaking. I sprayed a little electrical parts cleaner on the yellow connectors and where it connects to in the box. I reconnected battery and started the car and noticed now that the seat belt light went out when I engaged it(the light would stay out all the time regardless if the seatbelt was buckled or not before). Tried to clear the code and no luck.. Restarted it a few times and then the car would not restart. Radio works and windows etc but no lights come on the dash when turning key on and no starter clicking. Disconnected battery and reconnected and heard a click in that electrical box near the battery which I think is the pyrofuse.maybe? Before i open that box up any ideas? Thank You :
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Joined: Aug 2023
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From: MA Coast
W204 2010 C300 4matic Sport M272
Maybe the battery needs a charge. I hook up my charger whenever I play around with my scanner plugged in. If you dont have a charger use a multimeter to see what voltage the battery is at. Thats where I would start.
Thread Starter
Junior Member
Joined: Oct 2009
Posts: 39
Likes: 3
1986 porsche 928 1997 sl 600
Hi, Thank you for the reply. Battery is good. The headlights and all exterior lights work fine and the radio works. The warning lights dont turn on when I turn the key. and I have 2 windows down and am going to put plastic on those tonight because they dont work. I removed the electrical box and opened it up on my kitchen table and working on it now trying to remove the pyro-fuse to see if it is bad by chance but the 2 nuts that hold it in place just spin...lol... Thanks again. Nel
Nel
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2021 GLB250 FWD, 2023 GLA250 FWD, 2013 C250, 2015 GLK350, 2005 ML350SE, 2003 E320
See if this helps. The pyro fuse doesn’t click. You may have blown one of the fuses in the pre-fuse block.
https://mbworld.org/forums/c-class-w...good-batt.html
https://mbworld.org/forums/c-class-w...good-batt.html
