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Upper oil pressure sensor wire harness broken

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Old Apr 18, 2026 | 06:13 PM
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Cool Upper oil pressure sensor wire harness broken

OK. Was replacing the solenoid and internal lower wire harness for the oil pressure sensor (from inside the oil pan).. I broke the wire that attaches to the top of the oil pan - the one that after you push up the new wire harness connector through the round opening from inside the oil pan area that external wire that snaps on from the top of the crankcase.

Anyone have a part number for this wire? And a wiring diagram? Not sure how much of a pain it will be to replace this external wire harness. I hope it is a solitary wire harness and not built into a bundled harness?

It's a 2016 C300 W205 4matic 2.0L M274

On the image below it would be the wire that connects to the grey end on the left.


Last edited by kbeler; Apr 18, 2026 at 06:31 PM.
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Old Apr 19, 2026 | 11:04 AM
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broken harness connector

From what I understand... you broke the electric connector on the engine harness side to your oil pump control.

I'm guessing you likely have an active CEL showing to wanna fix that DTC, right ? Can you not let this be open circuit to get "normal" oil pressure ??

Try re-purposing half of a cheap 2-wires pigtail harness for "VVT magnet solenoid" I believe match the 2-wires oil pump solenoid.
See that Male/Female fit.

Last edited by CaliBenzDriver; Apr 19, 2026 at 11:13 AM.
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Old Apr 20, 2026 | 11:02 AM
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Thanks for your comment. I see that there is a lot of discussion on teh value of keeping that oil pressure at max with the mod you suggest. I will consider it, althought I am a keep it stock kind of person.

Still hoping ot find a part number for the broken wire/connector.

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Old Apr 20, 2026 | 12:35 PM
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internal vs. external

Originally Posted by kbeler
Thanks for your comment. I see that there is a lot of discussion on teh value of keeping that oil pressure at max with the mod you suggest. I will consider it, althought I am a keep it stock kind of person.

Still hoping ot find a part number for the broken wire/connector.
I totally agree there's value in being 100% stock... no question.

Perhaps your pump solenoid harness is bad inside the oil pan. That where pump harness fails.
Perhaps your harness connector is also broken on the engine side.

Test if its bad internally to save the time on not replacing connector.


> HINTS...
-- If there was a fault BEFORE you visited connector then failure is standard internal harness.
-- If the fault started AFTER visiting connector then it simply is external harness connection.

Hope this helps you chart repair steps.

Last edited by CaliBenzDriver; Apr 20, 2026 at 12:44 PM.
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Old Apr 22, 2026 | 11:06 AM
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Hello - thanks greatly for the comments. I know that the engine side harness connector is broken. I broke it taking it off.
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