sjm
Forum Member
I've been having an on-going issue where the fuel gauge will read full for a couple of minutes after a water crossing. Obviously, water was getting in somewhere, but once the water dried out, the gauge returns to normal.
In my foz, I have two sensors (connectors R58 and R59), one on either side of the tank. These connect in series to the body integrated unit, which reads the resistance, and sends the value via the CAN bus to the instrument panel.
The resistance range is very small, 2 ohms for full, and 31.9 ohms for empty. Clearly, water was splashing up onto the connectors and shorting out the pins, hence the gauge would read full for a while until the water dried out.
I spent some time trying to attack the issue from beneath the car, but eventually relented, and pulled out the rear seat to access the tank from the top.
This is what I found:
Obviously with all that dirt and dust, the slightest amount of moisture would have a serious effect on the resistance reading. This is what it looked like after a bit of cleaning:
Needless to say, the connectors have now been thoroughly cleaned, and waterproofed.
I mentioned this here because maybe one day someone else will have a similar problem, and this may provide some clues. Along a similar vein, if your fuel gauge is playing up, and not reading correctly - try cleaning the dirt from around the sensor connectors
In my foz, I have two sensors (connectors R58 and R59), one on either side of the tank. These connect in series to the body integrated unit, which reads the resistance, and sends the value via the CAN bus to the instrument panel.
The resistance range is very small, 2 ohms for full, and 31.9 ohms for empty. Clearly, water was splashing up onto the connectors and shorting out the pins, hence the gauge would read full for a while until the water dried out.
I spent some time trying to attack the issue from beneath the car, but eventually relented, and pulled out the rear seat to access the tank from the top.
This is what I found:
Obviously with all that dirt and dust, the slightest amount of moisture would have a serious effect on the resistance reading. This is what it looked like after a bit of cleaning:
Needless to say, the connectors have now been thoroughly cleaned, and waterproofed.
I mentioned this here because maybe one day someone else will have a similar problem, and this may provide some clues. Along a similar vein, if your fuel gauge is playing up, and not reading correctly - try cleaning the dirt from around the sensor connectors
