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From: Land of mountains, cheese, chocolate and watches
12' W204 C63 AMG coupe "T-Rex", 12' W451 Smart Fortwo Pulse (99' W202 C43 AMG + Ultima Can-Am sold)
Code P3628
Got an engine warning light shortly after starting up my C63 after a week or two of non usage.
Got my iCarsoft scanner out and ran the fault codes and came up with a P3628 indicating a "B4/15 (Fuel pressure sensor) has an open circuit or short circuit to positive".
Does this mean that the fuel pressure sensor could be faulty, or some possible wiring issue?
Can someone indicate to me where the fuel pressure sensor can be found?
Any other tips?
P.S. Tried searching the forum for P3628 but came up empty...
Last edited by DRBC43AMG; Mar 9, 2026 at 07:48 AM.
Reason: Added P.S.
The sensor is located at the front of the driver's side fuel rail. typically that code indicates either component isn't plugged in / wiring damage or the sensor is so far out of range it assumes it's not plugged in or shorted hence the code. I have seen injectors cause similar codes though if stuck wide open allowing fuel pressure to tank enough to make the ecu think it's a faulty sensor.
From: Land of mountains, cheese, chocolate and watches
12' W204 C63 AMG coupe "T-Rex", 12' W451 Smart Fortwo Pulse (99' W202 C43 AMG + Ultima Can-Am sold)
Originally Posted by roadtalontsi
The sensor is located at the front of the driver's side fuel rail. typically that code indicates either component isn't plugged in / wiring damage or the sensor is so far out of range it assumes it's not plugged in or shorted hence the code. I have seen injectors cause similar codes though if stuck wide open allowing fuel pressure to tank enough to make the ecu think it's a faulty sensor.
Thanks for the reply.
I'll do a check to see if the sensor is plugged in correctly, or if I can see any wiring damage
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