Thread: Battery discharge

I should have added to above the fact the auto electrician does not think it the SC80 it self but sees a draw coming from it - I have to check that out tomorrow.

I have since found out the the message appears at 12.2v and the SC80 cuts out at 12.0v another thread

Would it not be better if the cutout was say 12.3v. Not sure

Still confused about the ABG-25 roll in all this ?


Richard

The SC80 does draw a bit of current,but it is no where near 4 amps,maybe 40ma?,depending whether it is an earlier or later model SC80..There is a thin black wire that comes off the SC80 and goes to the body of the vehicle.If you disconnect it,the sc80 relay will not draw any current and the two batteries will be disconnected from each other.

Originally Posted by wbowner

Still confused about the ABG-25 roll in all this ?

Not sure about your problem Richard but it does sound like more diagnosis is required to find the source of the battery drain.

The SC80 protects the cranking battery and the ABG-25 protects the aux battery.
- SC80 cuts out at 12.0V so that the cranking battery can still crank.
- ABG-25 cuts out at a pre-set low voltage so that your accessories don't further drain your aux battery.

So the ABG-25 could only be involved if there is accessories connected to the sockets (that are draining) or it is faulty in itself.
I don't know if it's feasible for it to be a significant drain but you could always disconnect it to be sure.
However if you disconnect the SC80 as suggested by Paul there is no way for the ABG-25 to do anything.

Have you seen this Disco3 thread detailing how to test for battery draining issues:
DISCO3.CO.UK - View topic - Robbie's Guide For Battery & Quiescent Drain Testing
He recommends disconnection of all accessories before testing.

Cheers,
Scott
.

4 amps can't be right. That would completely flatten your battery in hours rather than days. It would be like leaving the interior lights on.

Hi Richard, did the auto elec take the current measurement just after you arrived?

If so, the reading will be wrong because the D4 takes about 3 minutes to go through it's SHUT-DOWN process.

You can make sure your D4 has completed it's SHUT-DOWN process by watching your PARK BRAKE light.

It remains on while the computers are shutting down, and only goes out once they have finished.

So next time, before testing, make sure your interior lights are TURNED OFF, and the PARK BRAKE light is off.

Then test for any discharge currents.

If your batteries are in good nick and fully charged, your D4 should be able to sit for at least 3 weeks before the SC80 turns off because the battery voltage has dropped to 12.0v.

You should still be able to start your motor for some time after the SC80 turns off.

Thanks for the info.

I had asked for a report but only read it when I got home as was in a rush. It didn't state all the info.

Unfortunately I then had to rely on me remembering what I was told which is a big mistake . So may be best to disregard my 4amp comment.

I will ring them tomorrow to clarify what I was told. Unfortunately they do not know much about discos and definitely nothing about the traxide set up.

Is the following true (based on what I have read)
1. The disco will issue the message when the battery hits 12.2v
2. The SC80 will isolate the aux and main battery when they batteries are 12.0v
3. The ABG-25 will turn off accessories when the aux battery drops to 11.6v or 11.8v or 12.0v or 12.3v ( depending on which switch is used)

So when things are standing idle I must have something draining the battery (this is what I wanted to know but still don't know).

If the above points are true then I can see how I am getting the message in the following scenario:-

My aux battery can go down to as low as 11.6v if the ABGV-25 is set to that value. If this is happening the main battery could be discharged to 12.0v before the SC80 jumps and isolates the two batteries. By then the low battery message would be issued.

So the cause of getting the message may be mainly due to the aux battery being drained which indirectly causes a drain on the main battery, to below the low battery message value, due to the way the SC80 works.

Is the above true or just a load of bollocks?

My batteries are being drained by something which is what I wanted to be found out but did not explain it properly to the auto electrician.

I will have a look tomorrow to see if I can see the black wire mentioned above.

Richard

Originally Posted by drivesafe

Hi Richard, did the auto elec take the current measurement just after you arrived?

If so, the reading will be wrong because the D4 takes about 3 minutes to go through it's SHUT-DOWN process.

You can make sure your D4 has completed it's SHUT-DOWN process by watching your PARK BRAKE light.

It remains on while the computers are shutting down, and only goes out once they have finished.

So next time, before testing, make sure your interior lights are TURNED OFF, and the PARK BRAKE light is off.

Then test for any discharge currents.

If your batteries are in good nick and fully charged, your D4 should be able to sit for at least 3 weeks before the SC80 turns off because the battery voltage has dropped to 12.0v.

You should still be able to start your motor for some time after the SC80 turns off.

Tim,
See my later post, I would appreciate your comments on my understanding.

I think I should have gone to an auto electrician familiar with discos and your units (can any one recommend one in Canberra).

I am unsure what they did and as mentioned in the other post I did not explain my situation properly to them. I should have got that sorted out first and gone to a LR specialist. I had asked the local LR dealer to look at the same issue awhile ago and they reckoned it was my brake controller but that was not true as I disconnected recently and still got the low battery message after a week.

Something is draining them which is what I want to find out about. I am about to leave my car idle for a couple of months so was hoping to sort it out. I will be leaving the car on a trickle charger driven by a seven day timer, due to the problem I am having I have to charge at least twice a week.

Richard

Richard

I'm in Canberra, I've got a traxide and a Nanocom with access to D3's. If you want a second opinion give me a PM.

My initial guess is 'suss battery' or 'suss battery connection'.

Regards
Trev