Completely Dead

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MacD
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Completely Dead

Post by MacD »

Traveller has been off the road for a while so have charged battery ...showing 12.8. Yet no lights no start no horn no fuel pump nothing at all . Turn the key and nothing happens. Help!
MCYorks
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Re: Completely Dead

Post by MCYorks »

When you switch on the lights or ignition does the battery voltage stay at 12.8 volts? Be sure to measure the voltage at the battery terminals. If it doesn't drop slightly then you probably have a bad connection.
MacD wrote: Sun May 30, 2021 12:51 pm Traveller has been off the road for a while
How long has it been off the road for? If the battery has been flat for a long time then they can become damaged and won't charge properly.
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geoberni
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Re: Completely Dead

Post by geoberni »

Lights and Horn are always from the permanent live, so irrespective of the build standard, i.e. whether there is the additional in-line fuse for lights or not, my guess would be a corroded/furred up connection on the battery or at the battery earth connection.
There's not a lot of options when it's completely dead.

You've hopefully got a Multimeter since you said it was reading 12.8v. That was presumably directly across the battery terminals.
Try it again Battery Positive post to a good earth on the body work.
Of course by 'Positive Post' I mean whichever post supplies the car, Pos or Neg as necessary.

A few quick checks with the meter will show up where the problem is.
For example, going from 'Earth Post' (the actual battery post not the cable clamp) to a clean metal earth point should be 0 volts reading.
Anything more than 1mV needs looking at.
Basil the 1955 series II

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MacD
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Re: Completely Dead

Post by MacD »

It’s been off for about a year but the battery has a shut off on the negative connection.
MacD
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Re: Completely Dead

Post by MacD »

Thanks for the help......think it might be the shut off connection that’s goosed. Glad the re is help out there,!
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geoberni
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Re: Completely Dead

Post by geoberni »

Ahh, so you have a Battery isolator, or perhaps one of those 'Disconnect Switches' like this:
Isolator.JPG
Isolator.JPG (53.7 KiB) Viewed 1871 times
I can imagine that can easily cause a problem if left open circuit for a year.
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MacD
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Re: Completely Dead

Post by MacD »

It’s a much clumsier one than the one in your pic.,it has been in the closed position but it’s in a bit of a state.
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Re: Completely Dead

Post by mogbob »

Some of the isolator / battery dis-connect clamps have a fused connector , by passing the clamp.With the knob on the clamp removed , the fuse allows a small load ( e.g.radio ) to be delivered. Whilst any attempt at starting the car ( the heaviest load on a battery ) would blow the fuse. If your set up has one of these , fitted by a previous owner then check the fuse is OK.
Still clean up all the starting circuit connections whilst the battery is not connected / live as suggested in previous posts.
Picture of what you might find attached :-
https://www.autoelectricsupplies.co.uk/ ... ategory/30

Good luck with the process of elimination.
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simmitc
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Re: Completely Dead

Post by simmitc »

Also, if it does have a fuse to prese4rve a radio, then if you have a radio, after a year it will have falttened the battery; and as observed above, if left flat, it may not now take a charge.
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geoberni
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Re: Completely Dead

Post by geoberni »

simmitc wrote: Mon May 31, 2021 4:11 pm Also, if it does have a fuse to prese4rve a radio, then if you have a radio, after a year it will have falttened the battery; and as observed above, if left flat, it may not now take a charge.
I agree that there are circumstances where the battery could be unable to hold enough amperage to even turn the engine over, but the OP of
...showing 12.8. Yet no lights no start no horn no fuel pump nothing at all .
makes me think this is a bigger problem that an exhausted battery.

I changed Basil's battery a few months ago because after charging, the Terminal Voltage was dropping by about 0.1v a day, with just the drain of his Tracker.
After about 6 weeks from being last charged/run, the starter bendix wouldn't engage due to lack of capacity.

If MacD has charged it and then presumably almost immediately tried the Lights/Horn/Ign and got nothing, that's effectively an open circuit / very high resistance.
Now knowing he has the isolator fitted, that's my first suspect, but a minute or two with a multimeter will soon find the issue.
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Re: Completely Dead

Post by PAULJ »

If I remember correctly the feed to everything comes off the start solenoid. Check the spade connection for Voltage
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