Charging Problem

Hi All.

I'm having a problem with my battery not charging.

Last Thursday I picked up my new (1994) 110, Drove from Portsmouth to Bridgend where I stopped for a rest for 30 mins. Got back in, Battery was flat. Called the AA jump started me and off I went. The guy checked and informed me the battery was charging. Got home, Battery dead again. Put a new battery in, has been ok for a few days (no long trips) slowly discharged though and dead again today.

AA Back out as I was in work, informed that it's not charging. The Alternator looks brand new so I'm guessing the previous owner may have had a similar issue.

Where do I go from now? Could someone help me with a basic wiring diagram and how do I check if the alternator is working? hat voltage to look for etc.

Many Thanks,

Wes

Also, it's not a problem with something discharging it when its off.

Get a multimeter onto the alternator and check what voltage its putting out with the engine on, it should be about 14.2v. It's more likely that the batterys goosed. Try and get a hold of a battery that you know is working and see if it does the same

It did, I took one from my bmw 320 and it did exactly the same.
Wes

Ah I see that, that's what I get for not reading posts properly. Strange. If the alts charging correctly and its still doing it even with a new battery, have you checked that the cables are in good nick and are secure?

That's my next check. Being new to Landys (and lazy) could anyone tell me what cables go where specifically. I'm determined this Landy never goes to a garage as I really want to maintain it myself as much as possible.

In the meantime I'll see if I can work it out from the haynes manual.

Thanks,

Wes

Had a similar problem . It turned out it was the main earth lead that runs from the battery to the chassis to the transfer box.

I took it off, wire brushed and then used emery cloth on the contact points , put it back with a bit of Vaseline and it's been fine for 2 months now.
It took about 10 mins.

Thanks Jay, I'll try that tomorrow.

Wes

Where exactly was the AA guy checking when he said the battery was charging? Was he actually testing the voltage to the battery (I.e. with the passenger seat out and battery box lid off)?

If not, it does sound like the others have suggested. If the alternator is kicking out 14 odd volts but the battery isn't charging, sounds like one of the main power or earth connectors is at fault. Trouble is with them is that they corrode over time and resistance builds up or they just have an intermittant disconnect. Usually they look normal though, so you have to wiggle them about to see if the voltage at the battery changes.

Seat out and directly from the battery. Not from the alternator, it looks brand new though. I'm wondering if the previous owner had this problem and blamed the alternator, bought a new one then found out it wasn't that.

Well it still might be one of the battery cables, but could be that the battery itself is knackered.

Can you disconnect the battery and test the voltage across the terminals after a drive, leave it disconnected and test again an hour later.

So the AA man checked that it appeared to be charging....
This rules out the alternator and wiring from the alternator to the battery.

You've swapped the battery for another one....
This rules out the battery.

So what are we left with?

Partial short?
Something left on?

Right is everything off when you walk away from it?
Is there a stereo, this could be drawing power?
Is there an electric fan that is wired wrong?
Interior light?
etc....

Nothing obvious? Ok check IF power is being drawn when the ignition is off.....
> Turn ignition OFF
> Disconnect the main power cable to the battery
> Switch the meter to AMPS
> Connect multimeter or ammeter so that one lead from the meter connects to the power cable and the other to the terminal of the battery that the lead was attached to.

Right now if everything is switched off it should read 0 or very close. If you have an alarm it will draw a tiny amount of power even when everything is off.

Is the reading above 0?
> NO --- This is correct

> YES --- Something is drawing power that shouldn't do.
>> If you have an alarm disconnect it - Does that fix it? YES - faulty alarm

If it isn't the alarm then you can narrow down the circuit responsible by removing one fuse at a time whilst looking at the meter until removing a fuse caused the meter to drop to 0. (it should be a permanent live circuit like clock, int light etc)

Once you have found the circuit that the fault is in then you can further narrow down the problem by removing each individual component on that circuit then checking the wiring but step by step.

So imagine it's a circuit that covered the interior light in the cab, one in the back and the clock. You would disconnect each light in turn then the clock. If one light being disconnected dropped the current draw to 0 then that is the faulty item

It's going to be a case of detective work till you find it.

What he said ^^^^^^^^^

Check the radio and clock first, (radio supporting pre-sets about 20mA and clock no more than 10mA), to save chasing things that aren't there ...

Also, check for a leak back thru the alternator, disconnect the plug at the back and see what happens to the current drain...

Apparently it's not losing power to anything when off either. 1st aa man said it was charging, second said it wasn't. It's going to the local garage tomorrow as my drive has scaffolding on it at the moment and work is crazy!

I'll let you know the outcome.

Thanks all for the help!

While I remember, the charge light has never come on. The volt meter gets a little lower each time I get in the car until the inevitable.

It sounds to me like the alternater is not charging. Meaning that the engine is running off the battery until it is discharged.

I would check all the alternater wiring is secure.

I would'nt advise it as I don't know what engine/ecu you have but the very old fashion way of testing is to start the car. While running disconnect the battery + terminal. If it carries on running it is charging. If it stalls it is not charging. Thinking about it though it might only work on on petrol.
Some frown on this old test as it can damage stuff but I've never had any issues. I've only ever used it on pre 1985 vehicles though.
Oh dear - showing my age!!

It was the alternator. Apparently cheap Chinese rubbish!