Solar Panel Trickle Chargers ??

[Dogu]

Hi

Has anybody used a Solar Power Battery charger on their Audi ?  I have an 18 plate A4 Avant and the car will be sitting for 3 or 4 months [due to work commitments].

I have an AA solar charger that I want to use to keep the battery topped up for that period so was wondering if these solar chargers are worth it or if anyone has had any issues with them ? Just want to check before I hook it up and leave it for 3 or 4 months !!

Many Thanks in advance..

 

[niedzial1983]

If not just disconect the battery 

[Magnet]

Hello Doug,

This car will be on an 'intelligent' charging system, and as I understand it, ordinary battery chargers cannot be used to charge the battery. 

Solar charger with ( I guess) very low charging currents suitable?? I don't know, and I think you are wise to check on this, and if it were mine I would be seeking some specialist advice.

A better route would be to invest in a the latest 'intelligent' charger - not cheap as I understand, but cheaper than messing up the car - and plugging this in via a timer - assuming the car is indoors. 

When you say you have work commitments for 3 to 4 months, does that man that you cannot get to the car at any time during that period? 

Kind regards,

Gareth.

[Faust]

Hi. I have recently purchased an 05' S4 convertible.

It's a lovely car, but the battery (which was only replaced in September) has gone flat twice! Both the Battery and alternator were tested today and both are ok.

I hadn't used the car for 6 days over Christmas, but I couldn't even use the fob to open the car yesterday.

Has anyone any advice or had similar issues? I was thinking of purchasing a solar trickle charger, but what I've read so far about them is not very positive.

Any help would be appreciated. Thanks

 

[Magnet]

Hello Patrick, 

(New) Battery going flat (on two occasions) while standing for 6 days = problem which needs to be investigated. 

Since you have already confirmed you have had the battery and alternator checked and confirmed to be OK, then the next check will be to assess the parasitic drain which is sapping the battery while standing.

In other words, something is remaining ‘running’ when it shouldn’t be - after the car has been switched off. Finding out what it is, can be a bit of a protracted investigation whereby the current drawn on the battery is measured after it has been standing for a minute or so (to allow the alarm to fully set). This should generally be no more than about 50 milliamps. If it turns out to be as I would suspect, then it’s likely to be a lot more than that. Assessing it will obviously depend on you having a suitable meter and the electrical knowledge to understand the results. In effect, it entails removing each fuse in turn until the unacceptable battery drain reduces to an acceptable figure. You will then have found the offending circuit, and you will then need to find which component is remaining ‘running’. 

Simple option, invest in the service of an auto electrician for an hour or so. 

OK, you could invest in a trickle charger rather than an auto electrician! So doing so will be just like keeping topping up a tyre which has a slow puncture - rather than getting it repaired. 

Having said all of that, it would be worth checking the obvious, such as glove box light not going out, boot light same. Good time to check will be after dark when glows may be evident. Original sound system still in place rather than a replacement one? Replacements and DIY wiring can be an issue.

I would not discount an alternator fault simply because the alternator output has be checked as OK. Alternators can still allow current to leak back through them on standstill, even though they can still provide an acceptable output. 

Disconnecting the battery (if you have radio code - if coded) is an option, but you will lose the alarm and may? lead to a need to reprogramme the key fob. 

Perhaps you could let us know how you get on Patrick.  

Kind regards,

Gareth. 

[Faust]

Hi Gareth.

 

Thank you for taking the time to respond with such a detailed and informative reply. I will do as you have advised and look to put your possibilities to my neighbour (when he returns from a holiday) who was a mechanic and will have the appropriate testers and knowledge to help... hopefully!

The glove box light, does go out when the car is locked, but I will also check the boot light when it is dark. At least that will be a start! I will definitely let you know the outcome.

Thank you again for your time

Kind regards.

Patrick

[Magnet]

Pleasure Patrick. All these things are sortable, despite being very frustrating in their effect! 

Just as an afterthought:-

Any in-boot systems such as Sat. Nav. unit, or CD changers? These can be problematic due to damp issues causing ‘white corrosion’ on printed circuit boards which can partially short out to the unit casings. 

Hope 2020 is kind to you.

Kind regards,

Gareth.