Technical Fuel gauge jumping...

[Stholt]

Recently had my fuel gauge start jumping randomly, and not showing full after topping up. I changed the sender unit in the tank thinking that would solve it, but no luck. The gauge seems to move a small bit, and occasionally jump, when the wipers move, so I am guessing it may be a wiring issue. Anyone here have similar experience and care to share? Just trying to save myself hours of tracing and testing wires.

 

[Communicator]

Recently had my fuel gauge start jumping randomly, and not showing full after topping up. I changed the sender unit in the tank thinking that would solve it, but no luck. The gauge seems to move a small bit, and occasionally jump, when the wipers move, so I am guessing it may be a wiring issue. Anyone here have similar experience and care to share? Just trying to save myself hours of tracing and testing wires.

I think that as your base vehicle is an x230 model, which is more relevant than year of registration, you may find this link to MHO forum interesting. Please report progress.

 

[Stholt]

Thanks for the link Communicator. Looks like I have a few things I can check before doing a trace on every wire. Appreciate it. I will post my findings

 

[Stholt]

The information in the link seemed to do the trick. I unplugged the connector from the back of the instrument cluster for a minute or two and plugged it back in. Ran the camper for a few minutes and the needle was rock steady. Taking it today for a fillup and a short trip so I will get a better idea if it is fully corrected.

 

[Stholt]

I was wrong...it is not fixed, it just holds the needle at just below half, no matter how much fuel is in the tank. More investigation is needed. I might open the tank back up and make sure the float arm isn't just stuck. I should have tried it before putting it in the tank.

 

[RobL]

Recently had my fuel gauge start jumping randomly, and not showing full after topping up. I changed the sender unit in the tank thinking that would solve it, but no luck. The gauge seems to move a small bit, and occasionally jump, when the wipers move, so I am guessing it may be a wiring issue. Anyone here have similar experience and care to share? Just trying to save myself hours of tracing and testing wires.

I had the same problem.( Left hand drive) It's quite a while ago now so from memory there is a white box behind the passenger glove box(I think this has been mentioned) I removed the plug and cleaned the contacts with toothbrush and contact cleaner. No trouble since. Some have mentioned contamination from coffee spilling down the back of the glove box.