DAF LF electrical fault

I hope someone may be able to help!

I’ve got a 53 plate LF which has a fault - it doesn’t affect the engine at all, but I’m drawing a blank with a) finding out what it is and b) how to fix it!

There are two issues - one clears itself, the other lasts until the ignition is turned off/isolator removed.

Issue 1 - dashboard back lights illuminate, fuel gauge and temp gauge to to zero (Speedo/air/revs unaffected), stop flashes. Any lights/wipers that are on, go off. Dials return to normal, back lights go off, abs light comes on, indicator/wipers return to normal. Abs light clears. This whole process takes no more than 5 seconds. Can occur continuously or not for 5 mins.

Issue 2 - it’s only done this twice, but still seems a relevant point! Issue occurs as above, but gets “stuck” in the flashing stop phase - so I have no lights, bright dials.

If we have issue 1, starts as normal. The issue can occur without the key in the ignition, ie as soon as isolator is turned on. If we have issue 2, she runs fine (with no indicators/lights) but if the stop light is flashing, she won’t start. Not even turn over. If I turn the isolator off, remove, reinsert, turn on - starts no issues.

I realise I’m looking for a needle in a haystack in all probability but I figure I can’t be the only person on the planet with this issue!

Things I’ve done:

Changed 1 corroded battery terminal (others are clean)

Wd40’d all plugs under bonnet - carefully taken apart, wd40, back together. Two of the top row showed signs of corrosion.

There isn’t anything obviously chewed by ratty.

I’ve asked plenty of experts but no one has managed to fix it or let me know what it is thus far…

Suggestions I’ve had:

VIC unit - spoke to VIC refurb Place who said this either fails or works, unlikely to show an intermittent fault

Alternator - I’ve only ever had one fail on a car and it seemed pretty terminal…this fault has been lurking for a year or so.

Damp - she’s definitely dry inside, plus surely even damp bits would dry in the current heat?

Sorry that’s long but if anyone can help I’d be massively grateful for any guidance!

I have found a man to plug it in tomorrow, but he’s the one who thinks alternator so just wanted to see if anyone else could possibly offer guidance.

Thank you!

You say you have cleaned the battery terminals …Have you checked behind the battery tray i think they used to hide a fuse there
VIC speaks to the dash panel …I see what your guy said when he says they fail or work …But like any computer they have brain ■■■■■ ,…Ie i had a LF no dash whatsoever nothing ,unplug vic give it 5 mins to discharge reconnect everything been fine since …Compare it to when your sky ■■■■ up ,you unplug it from the wall and reboot it …If you have a euro 3 check the wiring on the floor at the door where the diagnostic plug is …VIC should hopefully give you a clue to what is at fault along with the abs