The car has 53k miles. Today I replaced the fuel filter below the passenger side rear seat. I think I made a mistake not disconnecting the battery while doing the job. After the job is done I could not start the car any more. I kept cranking. Ran down the battery. The battery is being charged now.

Here are the facts:

1. There is no fuel coming out of the fuel pump. I checked the inlet to the fuel filter.
2. There is no voltage to the fuel pump. I jumpered the K96 fuel pump relay socket to get the fuel pump circuit always hot. I get 12 volts at the jumper. But there is no voltage at the fuel pump connector (blue/white wire, pin #2 X691). There is no voltage out of the blue/white wire (pin #9) at connector x11010.

I may have fried the fuse box control unit. Part# 6135 3455527-01.

Advice is appreciated.

 

Status update,

I removed the fuse box today to examine. I found the fuel pump fuse (#46, 20A) was popped. Put everything back with a new 20A fuse. As I crank the engine the fuel pump fuse popped again.

So I have a different problem now. The fuel pump circuit must have a short somewhere. When the fuel pump relay kicks in the relay pulled more than 20A current to cause it to pop.

 

Today I pulled the fuel pump cover and disconnected the connector to the fuel pump (X691). I checked pin #2 and pin #5 for continuity. It is continuous. So that is why fuse F34 keeps shorting out. The fuel pump is toast.

 

Hi Yaofeng, could you please point me to the location of the K96 relay on R56s? I suspect my K96 relay was fried. I know it must be somewhere in the fuse box but WDS just doesn't show any information about the K96.

 

It's been a long time...

The fuel pump relay on US spec R56 cars is on the passenger side kick panel forward of the door hinge. K96 is on the lower right hand corner of the board.

 

Thanks! I need to take apart the fuse box to access the K96 relay, right?

 

Actually I just measured resistance between Pin #5 and #2 of my fuel pump and it shows continuity (0.06 ohms). So I think my fuel pump is also toast? Do you know that is the nominal resistance for the fuel pump?

 

OK, I measured the resistance between Pin #5 and Pin #2 of my fuel pump and it shows continuity (0.06ohms), so my fuel pump is toast just like yours? I didn't suspect the fuel pump at first because when I connect a 12V jump starter battery directly to the fuel pump it works.With the car's battery, I only get 11V between Pin #5 and #2 without load (fuel pump disconnected) and only 10.3V with load (fuel pump connected). I already took the fuse box out and took it apart, it seems good to me, no sign of burnout, although I still couldn't locate the mysterious K96 relay...