d22 wont start sometimes

hello my navi played up for me today on the way to work, pulled into the servo went back to the ute my central locking didnt work, so unlocked with key... no alarm. put key in turned no dash lights... nothing worked except for the headlights. fiddled around with wires under the hood still didnt work, got jumper leads out and ran from 2nd battery to main one then the car started, got to work ok.. came out at smokeo to get my wallet and same thing happened. any ideas. the only thing i have noticed is that when this happens the interior light is on when doors r closed but looks like only on half power? have had battery and alt checked by sparkeys at work .please help.

have you replaced battery or taken battery leads off recently? Could be as simple as bad connection on terminals - but you had that checked hey?

Were any relays buzzing? You done any electrical works on the car recently?

havent done any wiring to the main in atleast 12 months its all to the 2nd one. the only thing i could think of was a short somewhere so im gonna replace a lot of the wireing.. and no buzzing of any kind

There could be some corrosion on one of the fusible links. Pop each fuse and immediately put it back in, that will remove any corrosion from the surface. It might be as simple as that.

It might also be the main negative lead from the battery down to the engine. Undo it from the side of the motor, wire-brush it and put it back.

Sounds a bit like a negative (no pun intended) problem to me. If it happens again, grab a jumper cable and connect to the block and the negative terminal of the battery. If it then starts, check your negative cable for corrosion etc at the battery side and the dodgy bolt onto the body of the car.

Confusing part of this is that your headlights work.. which doesn't make a lot of sense. Unless you have spotties fitted (and used a relay and the negative from the headlight circuit) or someone has wired the negative direct to the battery?

Also the interior light being on, but dim with the doors closed. That may be 'earth leakage'... I'm actually wondering if something may be amiss with the dual battery setup?

Sorry, hope there is something helpful in that rant.

Definately sounds like an earthing issue. Being that the headlights turn on try cranking while they are on and see if they dim a whole lot.
As said above check your main earths and
Possibly even wirin to second battery

I'm just wondering what would happen if the entire car is trying to earth through, say, the isolator and from there through some connection to a radio or something.

Trying to pull cranking amps through your UHF is likely to be the last call that radio ever does.

I'd check that earth strap before anything else.

thankyou for all your help.. i may have found the issue yesterday.. while tidying the mess of wires. it still didnt work. so i wiggled some of the larger bundles of wires that go to the fuse/ relay box with the ignition on i would hear the glow plug click on so chased the problem back to the bodgy spade 40 amp fuse for the ignition. was making a poor connection so i just put the 40 amp from the power windows spot (its only a dx) and no problems since then