Discovery 300 series V8i Electrical Gremlin

Hi All,

I originally posted this as being an alarm problem, but i'm not convinced that is what it is any more.

Symptoms. The problem normally starts with what sounds like the alternator breaking through on the radio. Sometimes this will go away by itself, sometimes it will get much worse.

When it is bad, the engine will struggle to idle, or maybe even cur out, but will normally re-start straight away.

Occassionally the car will simply 'die' electrically. Completely dead. Interior light, all switches, all lights everything. Sometimes the power returns after a brief pause, other times I need to disconnect and reconnect the battery.

This will result in the alarm failure symptoms I described previously (chattering relay, pinging etc.) So far, the EKA can be used to rest the alarm, and all is then well.

The battery never shows any sign of becoming discharged,as I would expect if it was faulty, or there was a dead short somewhere. Is there some sort of failure of the alternator that could cause this? Any other suggestions?

Currently resisting the gallon of Petrol and box of swan vesta fix!

MW

Reply to
mike whiskey
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Sounds like a fairly fundemental break in the wiring to and/or from the battery. Are all the connections clean and sound? Follow all the heavy cables and check every joint and connection. Check earth straps from engine block to chassis. May be worth taking the connections apart cleaning and reassembling with a *hint* of grease to keep the worst of the wet out.

The diode pack in the alternator is another suspect but I'd expect that to be fupped or not, not intermittent unless there is a connection problem.

Reply to
Dave Liquorice

Fusible link in main battery cable.

Reply to
Dave Plowman (News)

My immediate thought was a bad earth, I had similar weird symptoms on a '93 V8 Disco, turned out the earth strap was non existent between the chassis etc. Mine ended up earthing via the handbrake cable and melting it!!

Reply to
Andy

Good thought, would be checked when going through all the cables/connections from battery pos or neg. It might be in the engine fusebox rather than inline, hum what condition is the engine fusebox in?

Reply to
Dave Liquorice

Fusible links on cars sometimes go intermittent. Sounds unlikely I know with all that current but it does happen.

Reply to
Dave Plowman (News)

Thanks for all the suggestions. The engine fusebox looks fine without dismatling it, and I am unable to find anything wrong with the wiring.

That said, and I know this risks tempting fate, The thing has run faultlessly all week, not even a hint of noise from the alternator. I guess the threat of the petrol and swan vesta scared itinto submission.

I'll look a bit deeper at the weekend, but it will be hard to diagnose a fault that is not apparent!

Guess i'd better keep my multimeter in the car, and wait for it to break again!

MW

Reply to
mike whiskey

Very much doubt it, it's faking it, waiting till your back's turned and you're miles from home. Famous for it LandRovers!

Reply to
GbH

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