2012 C300 fuel pump not turning on in vehicle
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2012 C300
2012 C300 fuel pump not turning on in vehicle
I have a 2012 C300 Sport and today it decided to not start. I have followed the failure back to the fuel pump where I get 12V when there is no load (pump not plugged in) but 0V when the load is present (pump plugged in). I removed the pump and plugged it into a variable DC power supply and was able to verify the pump works and pulls ~3A @ 12V. I am not sure where the issue lies since the pump works and I am getting 12V at the connector when no load but cant drive the pump. I have checked every fuse and I cant seem to find a fuel pump relay in any of the fuse diagrams I have found. Any help here would be greatly appreciated.
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Joined: Mar 2015
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From: Sacramento, CA
2018 GLC300 4Matic; 2008 ML550 4Matic; 2004 C320
I have a 2012 C300 Sport and today it decided to not start. I have followed the failure back to the fuel pump where I get 12V when there is no load (pump not plugged in) but 0V when the load is present (pump plugged in). I removed the pump and plugged it into a variable DC power supply and was able to verify the pump works and pulls ~3A @ 12V. I am not sure where the issue lies since the pump works and I am getting 12V at the connector when no load but cant drive the pump. I have checked every fuse and I cant seem to find a fuel pump relay in any of the fuse diagrams I have found. Any help here would be greatly appreciated.
My E320 just came back from the dealer, as it did not get any fuel. Turns out the carbody harness connecting with the fuel pump had a bad pin in a connector, which did not make proper contact. The dealer re-pinned the connector and all is good now.
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2012 C300
Check the connector on the harnesses.
My E320 just came back from the dealer, as it did not get any fuel. Turns out the carbody harness connecting with the fuel pump had a bad pin in a connector, which did not make proper contact. The dealer re-pinned the connector and all is good now.
My E320 just came back from the dealer, as it did not get any fuel. Turns out the carbody harness connecting with the fuel pump had a bad pin in a connector, which did not make proper contact. The dealer re-pinned the connector and all is good now.
Thread Starter
Newbie
Joined: Dec 2017
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2012 C300
Resolved: The issue is pin 3 (+12V) of the internal 7 position connector. The pin on the internal harness is damaged and has signs of arcing. I currently have cleaned up the pin and bent it a bit for a better connection but need to replace the pin. Anyone know what type of connector these are? I originally thought they were AMPSEAL but that doesnt seem to be the case, any help wopuld be appreciated.
MBWorld Fanatic!
Joined: Mar 2015
Posts: 1,975
Likes: 265
From: Sacramento, CA
2018 GLC300 4Matic; 2008 ML550 4Matic; 2004 C320
Resolved: The issue is pin 3 (+12V) of the internal 7 position connector. The pin on the internal harness is damaged and has signs of arcing. I currently have cleaned up the pin and bent it a bit for a better connection but need to replace the pin. Anyone know what type of connector these are? I originally thought they were AMPSEAL but that doesnt seem to be the case, any help wopuld be appreciated.
