Battery drain???

rockdemon

rockdemon

Administrator
Staff member
Hi all,

I've got a new conundrum on PAE - not chased it through yet but thought i'd ask if there are any common causes...

For the last few days PAE hasnt wanted to start in the mornings, unless I disconnect the battery over night, so i think something is draining the battery.

It's not the boot light or interior light as i've removed the bulb from both.

I do have the longstanding issue of the horn going off when the door is open again (thought i'd cured that!) so this may be a part of it...

Any ideas gratefully received :)

Thanks,

Rich.
 
Apart from spurious earths etc, the only defect I can think of that could do that is the battery discharging through the alternator. Probably caused by a defective 4TR? Try disconnecting the alternator overnight and see if that fixes it.

Then you're back to oddities of bad earths and false earths etc.

Chirs
 
Well its just refused to start after a run so the alternator or battery can't be right. I'll get the voltmeter out tomorrow and see what appears accross the battery terminals when its running!

Rich
 
Hi Rich . I have many week points , The strongest of my week points being electrics ! Or vice verce !!! In either classics monthly , or practical classics this last month they did a feature on your same problem . The only thing i can remember that made sense was to remove a fuse at a time to isolate the problem . May take a few flat battery's and some cold morning cussing but may isolate the problem .
I'll see if i can look out the feature over the weekend .
 
Hmmm just read back through what you posted and what i replied , not being much help am i :roll: :roll: :roll: How about the auto box inhibitor if it seems to happen at random ???
Ps is the battery dead ? As in it wont light the lights up ?
Sorry if i'm going back to basics :oops:
 
Hi stina,

Think it's going to be the alternator, the 4tr that chris suggests or the battery, and i'm tending towards the battery as i gave it a proper blast on the way home (60 mph and a good 15 minute run) and the battery had less charge than when it started. It turns over, just very very slowly... it's got staying power too so i think the starter is fine.

I need to do a few preliminary diagnostics before i post more on this i think... Whether it runs around the 13.5v mark with the engine running accross that battery is the first thing... :)

Thanks for the suggestions... I know plenty about electronics but not necessarily in a practical or car context so I need plenty of help ...

now back to beer and Rock!

:D
 
Check the dongle under the carpet, might need a good clean, often forgotten about but damp/salt can cause it a lot of grief.
 
Hi tony,

do you mean where the positive cable passes through the drivers side floor?

Thanks,

Rich
 
stina said:
The only thing i can remember that made sense was to remove a fuse at a time to isolate the problem . May take a few flat battery's and some cold morning cussing but may isolate the problem .
Click to expand...

You can shortcut that a bit if you're lucky and avoid the wait for the battery to go flat. Switch everything off electrical that you can, then disconnect the battery and as you do look for a tiny spark, which could well be your drain. You can see it as you reconnect too. Then remove fuses and try it again, until there's a fuse removed that stops the spark. Touching the battery lead on and off should show you the spark every time. If fuses don't remove it, then disconnect things like alternators and relays.
 
Hi Harvey so you read that too , I'm not going mad then !!! I stayed with it and understood it until they said about running a cumpas along the loom looking for a deflection . I can understand the science , but not the practicality of being bent double under a dash trying to watch a needle deflect :roll:
 
ps interested on your opinion of the wasp :?
Click to expand...

I must admit its the one wasp track i can name! I like that track, but i dont know much of them to be honest... Do you have any more recommendations?

Rock here tonight has been at the drive in, super furry animals (which isnt rock really but very good) Ash Prodigy and Deftones...

I love variety in my music :)
 
Clock

the only thing in circuit that drains power is the clock, the switch contacts can weld closed causing a permanant current draw. Get a current meter (digital voltmeter) and place in series with the battery contacts (positive side) make sure you are on the highest current range to start (10 or 20 amps) and measure the current , it should be Zero or less than 20 mA, disconnect the clock and see if the current draw goes away. alternatively using the same method remove the fuses one by one until the current draw goes away once the current drops consult your circuit diagram and chech each termination until you find the guilty one.

Graeme
 
And it looks like the winner is graeme. Lots of current draw with clock in circuit becomes 0 when the clock is. Disconnected. Leaving it a while before trying yo restart it but first impressions are good....

Rich
 
You must log in or register to reply here.
Back
Top