Flat battery but why?

[Sunny43.5]

Ok now if my memory serves me well there was an issue with aftermarket radios causing havoc with the electrics due to a wiring issue , seems that some of the head units could cause someone using a diagnostic tool to end up with the stereo actually shorting out the diagnostic tool and wrecking the tool . Now I am not sure if it would cause a flat battery though seems a bit odd , now silly question did you fit an external amplifier at the same time , the reason to ask was there are some amps which use a strange system to turn them on and off . Most use a "Pcon "wire but others use a pulse via the RCA cables and if you select that without a matching head unit the amp will stay on even after the radio and ignition is switched off . Did this on a friends Honda took us a
trip back top the auto shop to find the switch to change .

[weonarok]

I'd be unplugging the head unit first to see if that rectifies your issue.

I have read where Amarok owners have had flat batteries after fitting cheap head units, even with the key removed. The problem is that they are designed to go Into a light sleep mode for a period (around 1/2 hour or so) so that if you were to return to your vehicle within this time the head unit should start up quickly and not need to reboot which can take over 20 seconds with some units. The fault was that they didn't fully turn off after this 1/2 to 1 hour of sleep mode and would continually place a drain on the battery rendering a flat battery overnight.

By the way, a battery that has been drained below 10v will have a very shortened life span and in some cases could actually wreck it completely. An hours drive may be enough to be able to top up the battery to start the vehicle but it would take a minimum of three hours to get to 100% SOC. A overnight trickle charger is the way to go which can be scored for as low as $20-30, but if you can afford it a 5 or 7 stage charger can be had for $100-150.




Cheers dave

[Transporter]

I'd be unplugging the head unit first to see if that rectifies your issue.

I have read where Amarok owners have had flat batteries after fitting cheap head units, even with the key removed. The problem is that they are designed to go Into a light sleep mode for a period (around 1/2 hour or so) so that if you were to return to your vehicle within this time the head unit should start up quickly and not need to reboot which can take over 20 seconds with some units. The fault was that they didn't fully turn off after this 1/2 to 1 hour of sleep mode and would continually place a drain on the battery rendering a flat battery overnight.

By the way, a battery that has been drained below 10v will have a very shortened life span and in some cases could actually wreck it completely. An hours drive may be enough to be able to top up the battery to start the vehicle but it would take a minimum of three hours to get to 100% SOC. A overnight trickle charger is the way to go which can be scored for as low as $20-30, but if you can afford it a 5 or 7 stage charger can be had for $100-150.




Cheers dave

The trickle charger is just what the name says, it trickle charges the battery and nowhere on earth will fully charge a flat battery in the T4 or any other van. Especially if there might be an electrical fault and the battery is constantly drained.

You could even struggle to put enough charge in it to start in the morning.

[weonarok]

The trickle charger is just what the name says, it trickle charges the battery and nowhere on earth will fully charge a flat battery in the T4 or any other van. Especially if there might be an electrical fault and the battery is constantly drained.

You could even struggle to put enough charge in it to start in the morning.

I was not indicating to trickle charge the battery while the fault was still present.

You have cured me, I will now refrain from touching the keyboard, read only.




Cheers dave

[The_Hawk]

I'd highly recommend the CTEK range of chargers, I've been using one for a few years on my Golf to top off the battery (especially in winter) when I know I'm not driving enough to charge the battery.

These units are designed to charge while all connected to the vehicle so I wouldn't think there would be an issue of charging while the drain problem is still present, sure if it's a huge drain it still wont charge the battery, but I can't imagine it's actually that bad.

[jets]

You have cured me, I will now refrain from touching the keyboard, read only.

Please don't take offence, your postings are of good value to this forum.

[Seano]

As others have already said it's that aftermarket stereo. There's original wiring in there so that you could turn the head unit on without having the key in the ignition. The head units at the time were programmed to run for a half an hour unattended and then switch off. It was very handy! I even had a aftermarket Blaupunkt unit that did the same thing. The current Pioneer unit doesn't though.

If whomsoever fitted the new head unit took advantage of this wire without consideration of what the head unit might do with the power then ...well...there's your problem.

Umai has also correctly (unsurprisingly) identified the box in front of the battery. If you remove it the van will never work again...

[Transporter]

I was not indicating to trickle charge the battery while the fault was still present.

You have cured me, I will now refrain from touching the keyboard, read only.




Cheers dave

Dave, I'm sorry if my post offended you, it wasn't my intention. I only wanted to highlight enough, so people remember not to use the trickle chargers in place of the proper battery charger.
...and as others said here, your posts are good value to the forum.

[Fossil]

Thanks for all the help guys. I disconnected the aftermarket head stereo and jump started it and took it for a drive for an hour or so and it's starting just fine now. I really do appreciate the help and this forum is one of the best I've ever seen with very prompt and helpful replies. Thanks again.