Bavaria 31 2000 Fuel Gauge not working

[Electra]

I have Bavaria 31 (2000) with a fuel gauge no longer working. I am a bit of a novice re boat electrics but on advice of couple of more experienced skippers tested sender with multimeter but no current or voltage was detected. The relevant circuit was definitely switched on. This lead to the conclusion that the problem lies elsewhere in the circuit.
I have yet to to access the fuel gauge itself and relevant cables to check connections. I need to partially dismantle the binnacle to get access but the rain came on!
The circuits used for lights, pumps etc are wired through the instrument panel and have mini circuit breakers. This one seems to be independent.
The wiring diagrams in the owners manual seem to have been reduced to A4 and are difficult to make out (and in German). Specifically we were unable to find the relevant circuit and to check if there was a fuse / breaker to check.
Any thoughts ?

[Salty]

For the fuel gauge on my B36(2002) to indicate the fuel level within the diesel tank, the engine control panel at the binnacle has to be switched on. That control panel, on my boat, has a small push button switch which latches on with one push and stays switched on until it becomes unlatched at the next push which cuts the 12 volt power to all engine circuits, there is no key controlled ignition switch as such. The fuel gauge is not dependent upon any of the circuits being switched on at the main switchboard for it to show the fuel level, though the main 12 volt battery switch, located under the chart desk, does need to be turned on. So, for your gauge to indicate the fuel level, and this assumes it is wired similarly, that small push button needs to be in the “On” position. You haven’t mentioned which type of engine control panel you have, so it may be that you have a key operated ignition switch, but either way it is odds on that your fuel gauge will not work until the ignition is turned on, and with the main battery switch also in the “On” position, so I would first look to see that you have power at the engine control panel when that panel is switched on.
On my boat the engine control panel is located near the bottom of the binnacle on the aft side, and is held in place with four screws. Once the screws have been undone the control panel can be eased out to enable you to see if you have any loose or broken wires hanging off. My binnacle also has a round access hatch located on the starboard side slightly higher up than the engine panel, and through which it is possible to view the back of the engine panel, but it’s not easy.
Good luck with your investigations.

[Electra]

Salty
It sounds as if my boat has similar configuration to yours. To check the fuel gauge circuit I ensured
1. the main 12 volt battery switch under the chart table was ON
2. the power off/on button was in the ON position.  When it is on, one of the lights (ignition?) at the bottom left of the engine control panel is illuminated for a few seconds.  Before the problem, the fuel gauge showing a level would also indicate if power was on.
The circuit was therefore definitely "on".  Measured electrical activity, both between the connectors on the fuel tank sender and also between the live feed and earth.  Nothing.  Conclusion - break somewhere else in circuit.
To investigate behind the engine control panel (i.e. remove the screws)  I will first need to remove the wheel and the auto pilot mechanism.  As I mentioned in previous post the rain came on that point yesterday so I beat a hasty retreat. 

I would still like to get hold of readable circuit diagrams. I have two, described as Panel 420, which mainly pertain to the instrument panel in the cabin.  Another two, described as Panel 421, pertain to the RCD panel which in my boat sits the right of the instrument panel.  Is there a website where readable copies can be found?   Can or would the Bavaria company be able to provide them ?   

 

[Electra]

Investigating the resources available on this site (Downloads) I have found readable circuit diagrams which although not identical in content to mine at least allow me to decipher or translate them.

[Salty]

That all sounds very similar to my set up, so I think you will need to investigate from the binnacle along the wiring there for either a loose or broken connection. If you have a separate access to the inside of the binnacle such as the rotating access hatch I have on the starboard side, you might be able to see the wire connections to the fuel gauge, it would be worth taking a look just to check that one of those connections hasn’t just fallen off before you do anything else.
Taking the wheel off to enable access to the engine control panel  is quite a simple task, rotate the central spinner/brake anti-clockwise to take it off. I can’t remember if there is a central nut that needs to be undone to allow the wheel to be withdrawn, but be very careful at this point not to lose the Woodruff key that locks the wheel and spindle together. The key will drop out very easily if you are not prepared for it. With the wheel removed either keep that key somewhere safe or put it back and secure it in place with adhesive tape.
Removing the engine control panel is a process of easing it off and gently feeding the wiring harness out through the bottom of the binnacle and then looking for anything obviously wrong. In the past I have found that sometimes spade type connectors have come off the connection point, but apart from that the system has otherwise been pretty reliable. If your problem is not down to a loose connector, then you will have to trace and follow the wiring from there back to your tank measuring unit while looking for any obvious fault. If you have an AVO meter you can check the circuitry fairly easily for continuity.

[Electra]

Fuel gauge now working again!  Woo hoo.

Removing the engine control panel exposed a loose connector which was pushed back into place and completed the dodgy circuit.  Problem solved.   

Thanks for advice, Salty.

[dawntreader]

...." a loose connector which was pushed back into place and completed the dodgy circuit.  Problem solved. " 

I would recommend replacing the 'loose' connector else the problem may well re-appear