No dashboard lights/engine start - but other lights working.

[chief]

A while ago, my Mothers' Bongo had its' MOT, at which time the garage charged up the battery (hadn't been used in a while).

Just recently I had the batteries out myself since again, it hadn't been started since the MOT and topped them up as she'd been thinking of going away on holiday.

About a week ago we kept hearing a car alarm going off, looking outside we never saw any indicators flashing so thought it wasn't us.

Few hours later it turned out to be us, the fob (cobra alarm) turned it off, turned it back on and everything seemed fine.

However yesterday we discovered that the alarm no longer works at all and we have to use the key in the door.

The interior light (above the windscreen) works when the doors are opened.

Once in, putting the key in the ignition starts up the reverse/AFT alarm (why is this, the roof is closed, no main lights etc. on and it was in Park? the door was open mind now I come to think about it), but no dashboard lights come on at all and turning the key does nothing.

I checked the fuse boxes (three under the bonnet, one down by the steering wheel, and the two in-line fuses of the alarm itself).

The fuses don't look blown, but all (interior and bonnet) of the PAL fuses are coated in verdegris.

The one fuse I didn't check was the Main 100amp, after finding it bolted in place, but presumably the interior lights wouldn't be working if it had blown?

We don't have any spare PAL fuses, so are any of them interchangable between bonnet and interior fuse boxes for testing if there's one we should try?

I figured I'd ask here in case it's something easy to troubleshoot (my worry is the alarm has failed and is immobilising the Bongo) before it gets booked in anywhere.

The alarm was never fitted by us, I haven't got the documentation to hand but think it's quite an old model.

Thanks

[g8dhe]

Lots of different problems there which tends to suggest that your battery(s) are virtually dead, the fact that you have had to charge it and its not been used much suggests that the battery needs replacing not just charging, they don't last for ever and die much more rapidly if left for any time in a discharged state. Ideally you need the battery testing before simply hoping its the fault and changing it, as otherwise its very easy to ramp up the repair costs by changing things that aren't the problem.

[chief]

The Varta batteries are only a couple of years old, and I topped them up as a precaution - only took an hour to do both, so not really deeply discharged since the MOT.

Although I couldn't tell you if the garage that charged them for the MOT also tested them, our own charger when I topped them up didn't report any doesn't take charge/doesn't hold charge errors on its' self-testing stages.

So I'd be inclined to rule out the batteries, not saying it couldn't be them but if there's anything else that's easily checked that you could recommend that would be great.

[chief]

New battery (old one would charge, but then would rapidly drop to 2volts within minutes) and empty sediment tank, and the following is now how things stand with the Bongo.

Dashboard Lights work with a charged battery.
The alarm is working - went off with my ear right next to its' speaker .
Turn the key (after waiting on glow plug light going out), engine attempts to start, but fails.
Subsequent attempts seems to flatten the battery, or to put it another way, the ability to start it gets weaker and weaker until turning the key doesn't do anything.
The diesel guage is sitting mid-way between the E area and 1/4 so presumably it has fuel enough.

I only tried after charging up the primary battery, not the secondary (right side of bonnet while facing the engine bay) which is where all the leisure stuff seems to hook up to, I take it only the primary starts the engine?

Any other suggestions?

Thanks