It's not a jimny so I need help.

I have need of its 3 tonne towing capacity 4 times a year and I need it to work then. The rest of the year I would like it to work for whenever I feel like taking it out, I don't want to feel forced to use it when it would be better to use the jimny just to keep the cruiser happy.

If you fit a C-Tek on permanent charge the battery will be charged as and when you need it. You will not need to drive it to charge the battery, the charger does it for you. as I said earlier, outflank the bugger.

Roger

And as I said before it would be my elderly and disabled parents who would bear the brunt of connecting the charger as they are the main users of the car. The opportunity to get it wrong or forget is high and not really fair on them which then means me looking after it which I hardly have time for. Ultimately I'm of the opinion that a land cruiser of all things should be able to just be used even if only for 25 miles a week without intervention. Had I known before buying it it was going to do this I wouldn't have bought it.

And as I have said before, I am a realist, I don't batter my head against a wall, I look for a door. Fit the C-Tek permanently to the car with a simple extension lead to a suitable power point and put a note on the steering wheel telling the driver to disconnect it.

Roger

What is wrong with wanting my car to be right? Why should I have to have my vehicle devalued, because I can't currently sell it in good faith knowing it has a fault?

Next question. If the battery is rated as 75Ah and I placed a draw on it of 1 amp it will maintain that for 75 hours?

Lambert wrote:

What is wrong with wanting my car to be right? Why should I have to have my vehicle devalued, because I can't currently sell it in good faith knowing it has a fault?
 

But does it have a fault?

It has a draw on the battery which is within the manufacturers specification when not in use, it has been designed to be used in a certain way as agreed with the manufacturers algorithm. you are (potentially) wanting to use it outside of that algorithm, is that a fault?

Is there an option to fit a larger battery, is there a winter option for twin batteries, I thought some LC had them, our Surf did, but it was an import. 

With regards to the charger I get the impression that you think that it will be a hassle, having to open the bonnet, connect the leads etc. I'm not sure that is what is being suggested if it is then I am with you, but what I would expect to be provided is a discrete plug/socket in the grille, under the bumper etc. that you would simply connect the lead. As you are towing I presume you have an electric socket, depending on how it's been wired you could potentially introduce 12V at that point which would go all the way back to the battery.

I suspect that if you used the car on more regular basis then there would be no issue, which means you could should you wish sell the car with a clear conscience, however I would also suggest that whatever you replace it with is likely to have the same issue.

Every month I put the Audi on charge and it takes an hour to charge the battery. I then charge the Jimny and that takes 1.5 hours. In 10 years the Audi has done 33,000 miles. The Jimny has done 14,000 miles in 4 years. I changed the Audi battery 2 years ago - same size - and the Jimnies after 3 years - uprated. We don't have a problem with either. I don't consider that charging the batteries every month means that I have admitted that there is something wrong and I can't solve it. There may be a problem with modern day systems that to requires the electronics to act in a strange way to eek out every drop of fuel and I accept that because I cannot change it. I fight that which I can change and accept that which I can't.
Yes, my LC had a winter kit that included twin batteries and a heater built into the fuel filter and as long as I changed the batteries every 10 years the system never faulted. Didn't even have to charge them!

Roger

Yeah I'm not really sure why mine is single battery it certainly has a second battery tray? I assume being the most basic of the range the accounts department saw an opportunity to save money either that or it's considered to be simple enough to not need it?

The way the service guy was talking the charger didn't sound like a mounted thing just something to attach but they were determined it would be something they would supply rather than fund one I might obtain.

Lambert wrote:

What is wrong with wanting my car to be right? Why should I have to have my vehicle devalued, because I can't currently sell it in good faith knowing it has a fault?

Next question. If the battery is rated as 75Ah and I placed a draw on it of 1 amp it will maintain that for 75 hours?

In theory yes, but in practice no.  As the battery discharges the voltage drops and the load which took 1A now takes slightly less. Plus as a battery looses charge the internal resistance increases, this does a number of things:

it reduces the peak current, hence difficulty in starting; and
the terminal voltage drops further under load than the no load voltage, thereby reducing the current flow even more.

Then don’t forget that a battery is less able to give up its charge (or charge up) when it is cold.  Terminal voltage drops and internal resistance increases with cold temperatures to both limit the amount of power you can get out of your battery.

Robin

 

OK thanks, I have been trying to work this out mathematically and in order to support the alleged maximum tolerance load that Toyota claims of 0.03A the 75Ah battery should be lasting over a hundred days if just left alone or conversely if their other assertion that the car should be able to stand for between 2 and 4 weeks so let's say 3 weeks is correct then the battery could be seeing a draw of 0.14A as after 3 weeks if I leave it that long it's touch and go if it will start. In other words by their own reasoning something is wrong as it should last longer than it does if the drain is within tolerance even making allowance for it not following best case mathematical calculations?

 About 18 years ago I had a similar problem with battery drain due to not using the car for long periods but in my case the battery was flat within a couple of weeks.  Under warranty the dealer replaced the battery a couple of times and did  electrical drain tests etc but never found the cause.  They eventually told me the car was designed to be used not sit in a garage. I gave up trying to sort the problem and kept the battery on charge while it was not in use for the 10 years I had the car.  Because my Defender has little use I use a Ctek charger which I like others would recommend in your situation. As someone has already mentioned Ctek  make a plug which goes into the towbar socket providing it is of the correct type or you could use the cigar lighter if you have one.
​​​​​​One thing the dealer didn't do was change the alternator because the output was within tolerance.  I have since learnt that alternators have a diode which if faulty will cause battery drain even when the vehicle is turned off and the alternator is not operating. 


 

Interesting. I have to trust that both the dealer and the independent auto electrician will have thought of testing the alternator and it's associated control units but I will ask the question directly