Battery drain problems.....

[1972nail]

Our 2003 3.0 E85 has been intermittently draining the battery for about 5 years now. When I say intermittently I mean it can be OK for months and then suddenly for no reason a flat battery over a weekend, then once charged all is OK for another while......until this week!
I finally have had the problem persist long enough to be able to diagnose and trace the culprit. To cut to the chase, the sat nav, CD changer and phone circuit is causing the problem.
Pulling fuse 49 seems to have cured the problem but the pop up screen is also on that fuse and no longer pops up. This means there is no radio display.
I'm guessing that the root of the problem is in the actual CD changer or the sat nav DVD player but gaining access to pull the plugs means quite a bit of interior dismantling, which is not ideal out on the drive in November.
My question is, will the screen pop up again and display radio information once the fuse is reinstated after the I've spend a lot of time and effort on pulling the plugs on the offending units?

 

[enuff_zed]

You should be able to access the plugs from behind, simply by removing the bulkhead carpet. Doesn't have to come right out, just lift it from the bottom.

 

[1972nail]

You should be able to access the plugs from behind, simply by removing the bulkhead carpet. Doesn't have to come right out, just lift it from the bottom.

No, unfortunately you can't. I was able to disconnect the telephone plug though.

 

[enuff_zed]

You should be able to access the plugs from behind, simply by removing the bulkhead carpet. Doesn't have to come right out, just lift it from the bottom.

No, unfortunately you can't. I was able to disconnect the telephone plug though.

Perhaps I wasn't very clear, sorry.
I omitted to say, from within the boot.

 

[1972nail]

You should be able to access the plugs from behind, simply by removing the bulkhead carpet. Doesn't have to come right out, just lift it from the bottom.

No, unfortunately you can't. I was able to disconnect the telephone plug though.

Perhaps I wasn't very clear, sorry.
I omitted to say, from within the boot.

No, you can't get at the back of the units from within the boot. You can see about 1/3 of the changer but not access the plugs on either unit.

 

[enuff_zed]

No, unfortunately you can't. I was able to disconnect the telephone plug though.

Perhaps I wasn't very clear, sorry.
I omitted to say, from within the boot.

No, you can't get at the back of the units from within the boot. You can see about 1/3 of the changer but not access the plugs on either unit.

I beg to differ, having done exactly that only a couple of months back as a way to test another CD unit, but no matter.

 

[1972nail]

Perhaps I wasn't very clear, sorry.
I omitted to say, from within the boot.

No, you can't get at the back of the units from within the boot. You can see about 1/3 of the changer but not access the plugs on either unit.

I beg to differ, having done exactly that only a couple of months back as a way to test another CD unit, but no matter.

Not in our car, there's a small aperture about the size of a mobile phone for the cables to pass through, the rest is just the steel bulkhead panel.

 

[enuff_zed]

No, you can't get at the back of the units from within the boot. You can see about 1/3 of the changer but not access the plugs on either unit.

I beg to differ, having done exactly that only a couple of months back as a way to test another CD unit, but no matter.

Not in our car, there's a small aperture about the size of a mobile phone for the cables to pass through, the rest is just the steel bulkhead panel.

Too dark to go out and take a photo, but I know for certain that I can see the rear of the CD player and its plugs.
Well anyway, good luck.

 

[inkey$]

I beg to differ, having done exactly that only a couple of months back as a way to test another CD unit, but no matter.

Not in our car, there's a small aperture about the size of a mobile phone for the cables to pass through, the rest is just the steel bulkhead panel.

Too dark to go out and take a photo, but I know for certain that I can see the rear of the CD player and its plugs.
Well anyway, good luck.

Yep - Another vote for managing it too from the boot, through the bulkhead. Its tricky but there is enough space in there to disconnect the rear plugs.

 

[enuff_zed]

Not in our car, there's a small aperture about the size of a mobile phone for the cables to pass through, the rest is just the steel bulkhead panel.

Too dark to go out and take a photo, but I know for certain that I can see the rear of the CD player and its plugs.
Well anyway, good luck.

Yep - Another vote for managing it too from the boot, through the bulkhead. Its tricky but there is enough space in there to disconnect the rear plugs.

Thank you!
Thought I was goimg mad for a minute.

 

[inkey$]

Too dark to go out and take a photo, but I know for certain that I can see the rear of the CD player and its plugs.
Well anyway, good luck.

Yep - Another vote for managing it too from the boot, through the bulkhead. Its tricky but there is enough space in there to disconnect the rear plugs.

Thank you!
Thought I was goimg mad for a minute.

Nope, its definitely doable, so you don't need to start taking the pills just yet, Martin :lol:

 

[1972nail]

Back to my original question. Will the pop up screen still work to display the radio information with the navi unit and CD changer disconnected?

 

[enuff_zed]

Back to my original question. Will the pop up screen still work to display the radio information with the navi unit and CD changer disconnected?

Try disconnecting them and see what happens

 

[1972nail]

Back to my original question. Will the pop up screen still work to display the radio information with the navi unit and CD changer disconnected?

Try disconnecting them and see what happens

That's the problem, while the CD changer might be possible through the boot the sat nav unit is impossible as far as I can see. The CD changer is on fuse 48 and the sat nav on 49. It's fuse 49 that the drain is through so pulling the CD changer is not necessary.
On the drive in November is not the time to start to struggle with removing a large chunk of the interior just to see what happens. I'd rather be certain of a positive result rather that struggling with a futile mission at this time of year.

 

[1972nail]

Today's update....
With fuse 49 removed and the sat nav drive isolated there is still a 1.9A drain on the battery so my search continued.
A bit of poking about in the boot today and I found a small 6v battery. Once removed, I checked it and it was totally dead. The battery is the back up for an old style tracker unit.
Googling a bit turned up that if the backup battery is dead the tracker can't go to sleep and draws a constant current of about 1.9A from the car battery.
Tomorrow will see the tracker removed and the drain checked again. I'll then try reinstating fuse 49 for the sat nav to see if my original diagnosis of the sat nav being at fault was incorrect.

 

[chanlon1]

Complete beginners naive question. How do you test for a drain on the battery.
I have the same issue but no idea where to even start.

 

[1972nail]

You'll need a multimeter which can register at least 10A and preferably 20A. You'll also need a supply of the small protection fuses for inside the multimeter because you will blow them!
Then you need to check out a lot of YouTube videos on the subject and get your head around the fact that modern cars need time to go to sleep and wake up unen you open the door or connect the battery up. This all can take a lot of time.
If you are not up for the learning curve it's best to take it to a good auto electrician and let them take the hassle. They also have more sophisticated equipment that can reduce the time taken.

 

[colb]

Loads of Youtube videos on how to do parasitic battery drain tests here
https://www.youtube.com/results?search_query=parasitic+battery+drain+test

 

[chanlon1]

Thanks for the pointers. Electric was never my strong part in Physics at school. So I’ll probably go to my local auto electrician.
I have pulled Fuse 48 (CD changer) to see if that makes any difference first.