Odd electrical power problem

Hi All,
I need some help with an issue on my 96 4.0 v8 P38A. I've only had it a week and it's had a starting problem since day one. I bought it privately, so no comeback!

It was fine when collected, drove round to my in-law's house and home again without a problem until the front left indicator fell off and smashed, losing the bulb. Ever since it has had a starting problem. The indicator may have been a coincidence, but I thought I'd mention it anyway.

The car has no electrical power at all, no ignition lights, no hazards, no radio, nothing! I charged the battery for 6-8 hrs and measured 12.2V, left it unplugged overnight....still held 12.2V. I plugged it in to the car and it started. Checked 4 times over the next day and it started every time.

The next day however, nothing, no ignition, no central locking, doesn't turn over, etc. I measured the battery voltage whilst plugged in to the car and it was 3v. I unplugged the positive terminal and rechecked the voltage across the battery and saw it rising to 10.5v. Reconnected the +ve terminal and it instantly drops to 3v again, unplugged it rises back to 10.5v.

This suggests that something is drastically draining the battery. I have 3 question;
1) Can this be caused by the bulb getting smashed and perhaps shorting a wire somewhere?
2) How do I begin fault finding this?
3) Would you expect to see NO electrical circuit working at all?

Sorry for the length of the post, but I am at a loss, any help would be gratefully received.


Many thanks
Jupi

Battery severely fecked - time for a new one, get the biggest you can find that fits...

The RF Unit is the chief cause of battery drain...search the threads on here about it....

Sounds like the previous owner started it before you arrived to get it charged up. Could be the bulb holder has a short but I wouldn't have thought it would be that much. When it's running does everything work as it should?

I would trace the electrical connectors back from the indicater block and see if it's been pulled out further up the loom.

mick

EDIT: As saint said, P38's like constant, consistant power and get techy if they don't get it. Get a heavy duty one (one for a Diesel) and go from there.

Thanks guys, much appreciated.

Supposedly the battery is only a few months old......hmmm
:violent:

unplug the rf unit and see what happens if you let folk no where you are based they may be able to help a bit more though

Same as when I got mine. Ended up being the RF unit. Replaced and been fine since but I believe tricky to get now.

mutsnutz said:

unplug the rf unit and see what happens if you let folk no where you are based they may be able to help a bit more though

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+1, if the r/f is picking up spurious signals it will wake up your alarm and relock your doors every few seconds. This will flatten your battery and eventually burn out your door lock motors. Recharge the battery, take it to your local ATS/Quickfit etc and get them to test it. If its duff then search on here for replacement battery. If its ok then disconnect the aerial wire on the r/f till you get a replacement. Depending on year, pre 2000 I think, you can disconnect the r/f completely if you don't mind using the key instead of the remote.

I would take a look at the under bonnet fuse box. The fact that you've only had it a week means this vehicle could have a raft of problems. Having the indicator fall out tells me that someone has been fiddling with the car.

Rick-the-Pick said:

I would take a look at the under bonnet fuse box. The fact that you've only had it a week means this vehicle could have a raft of problems. Having the indicator fall out tells me that someone has been fiddling with the car.

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Thought that was normal build quality , but yes, give the fuse box a sniff, see if you can smell burning.

12.2 volts after charging means the battery was as near as makes no difference fecked, you should have at least 12.8 volts an hour after it came off charge. Could be the alternator is not charging. Forget all the stuff about battery drain for the moment and get a decent battery on it. You could try battery megastore on line for an Alphaline 100CCA 135 Ah battery. After that, check the alternator is charging, you should have 14.2 volts at 2K rpm. If all that checks out and you still have a problem you can start looking for battery drain problems.

Thanks very much folks.
I will get myself a new battery, but I did start looking at a few other things. The fuse box does smell a bit "electrically", not burning as such.
having checked for a drain, I did find that Maxi Fuse 1 (one with a "read the manual" icon drew about 0.4A and having removed that fuse and left the battery overnight, it started fine this morning. I don't know how old the battery is, so it might be worth getting one anyway, a nice beefy one, as suggested, but that drain on Fuse 1 is interesting.

Sorry - don't know if this is allowed (mods please remove it if not) but I found this thread:- Battery Mysteriously Going Flat Overnight... SOLVED!!! on 'another forum' very interesting in regards to battery drain. See post #10

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