weird things happening with ignition and automatic transmission

[Jona]

Any ideas anyone, when I switch the ignition on my bongo to start it up instead of the glowplug light coming on, the radiator fan starts up. It still starts without the glowplugs warming things up but when it is put in gear it is very sluggish (almost like the clutch is slipping on a manual box) and it struggles to change gear once it is going. Sometimes this rights itself after a while, sometimes not! any clues?

[g8dhe]

Do you have the Air Con switched on ? This forces the radiator fans on to ensure that the refrigerant can be cooled down! If you turn the air con off then the radiator fans will only respond to the engine temperature sensors.

[Northern Bongolow]

if you try and start it and the glow plug light doesnt light and the fans come on then this suggests the starter battery is duff, or there is an earth problem, maybe on the battery neg terminal, or the engine earth that earths the starter motor. there are 2 earth cables one from the engine to body and the gearbox to body on the passy side low down, remove and clean them up and refit. the battery neg terminal bolts to the body inside the wing.

when starting the engine with a flat (ish) battery and there isnt enough juice to start the engine the front fans come on.

the gearbox is very susceptible to battery voltage to operate correctly so a bad earth to body or bad battery just after a start up situation may be the cause when the duff battery has been hammered again.

[Markas]

As soon as I saw the first few words of the OP's title - 'weird things happening with ignition' - I thought of the battery. A flattish battery on modern vehicles can cause all kinds of electrical mayhem.
A few years ago I had an MG ZT; when the battery on that died, on Christmas Eve in Tesco car park no less, it announced its demise with a crazy light show on the dash to rival any Christmas tree and fun central locking/ hazard light gremlins Eventually it turned out the alternator was dying on that car.
I didn't take it all quite so flippantly at the time!!

[Jona]

cheers guys, I'll investigate further