At my wits end.. hybrid battery drain

[Borister]

Hi, I have a Hybrid Alphard conversion 2007, and I’m at my wits end. If I don’t drive it every single day the battery is flat and I have to jump start it. My local garage are out of ideas and I don’t live in a town so it’s going to be a real pain to find a Toyota dealer that may help. The 12v battery was replaced last year due to a ‘bad cell’ - I had to call out the RAC at the time., and the battery health of the new one has been checked several times. This fault was happening before I got the new battery last summer.

There are no autoelectricians locally who can help.

Im out of ideas. Any suggestions or advice?

[Sunny]

It appears to be a hybrid conversion trait....rather like Fords having a puddles in front passenger footwell!....

I have this problem and now carry a Noco boost GB70. And if it doesn't start you just clip it on and start your engine. Sorted and no stress!

[Borister]

Hi Sunny, would a Noco boost GB70 be something an incompetent woman on her own could fit/use? Asking for a friend….. I was very excited when I learnt how to jump start my hybrid with a regular old car with a black and red battery connection..

[Montecrist0]

Hi, fit a battery isolator switch, you have to reset windows after switching off and on but better than none starting.

Don’t forget to switch off when leaving your vehicle, good anti-theft device too.

[Rojie]

You should be able to use a Noco, and there are other brands, without mishap.

 

Just ENSURE the terminals are connected correctly, and the Noco remains fully charged at all times.

 

Isolator switches are quite cheap, although you will probably need a garage to fit it for you.

 

However, isolator switches do not resolve the issue causing the battery drain, but do provide a work around.

 

I do not have a hybrid, but believe they do not have alternators; so that is not the problem.

[PaulE]

I have the same issue and I think most hybrid owners have this even with modern ones. It is possibly a parasitic drain which would be difficult to find on the Alphard Hybrids as the internal fuse boxes are almost impossible to access but also 12v batteries go bad very quickly if not charged regularly and hybrids only have a low output alternator so needs a long drive to charge up, I think they are more for "topping up" than fully charging. I have found it worth taking the battery off and giving it a full charge regularly- but see below.

 

However I have found recently a possible work around.

 

I have a Noco Genius 5 battery charger and I had to regularly take the battery off and charge it fully (I have a spare to swop). I found on a Youtube someone fixing a (semi) permanent Noco charger connection with eyes rather than crocodile clips to the battery post bolts. This then connects to the Noco charger and allows on board charging without removing the battery. I have tried this yesterday and worked fine. I intend to use this regularly to top up on days when not using the van. I do have the van off the road on my drive and run a long power cable through a gap in the driver window allowing the charger to be in side. I can then lock the van and give it a boost for up to an hour or as required. I then remove the charger leaving the cable connected and the end hides under the carpet. If you don't already have a Noco Genius charger they do the Genius 2D (the "D" is important)  which is designed to be permanently connected and is very small so can be hidden. I will leave Amazon links below.

 

I have taken professional advice on whether this is safe to do and the answer came back is that charging with the battery connected to the vehicle should not be any different to charging with the alternator and less potentially damaging than using a booster pack ( I do use a Noco booster and keep one in the van- very good product) and the Noco chargers are well made and have protection circuits (honest- I am not sponsored ). I will try and put photos on at some point in the future.

 

Hope this helps.

 

There are 2x alternative to the lead - one with M10 eyelets and one with M6- I used the M10 and these are a bit large but work, I had to cut a small slot in the red plastic cover to accommodate the positive eyelet.

 

NOCO GC002 X-Connect M6 Eyelet Terminal Accessory for Genius Smart Battery Chargers : Amazon.co.uk: Automotive

NOCO GC008 X-Connect M10 XL Eyelet Terminal Accessory Genius Smart Battery Chargers : Amazon.co.uk: Electronics & Photo

NOCO GENIUS2DUK, 2-Amp Direct-Mount Onboard Charger, 12V Battery Charger, Battery Maintainer, And Battery Desulfator With Temperature Compensation : Amazon.co.uk: Automotive

[Borister]

Thanks Paul - that’s very comprehensive. I’ll take a look at the links. 

[Borister]

Hi Paul, maybe a dumb question, but here goes…. My 12v battery only has a red connection (positive). When jumping starting from a regular car I earth the black connector (negative) on the bonnet somewhere like the RAC man showed me, so how would the Noco Genius 2D work when the black eyelet is expecting to hook onto a negative connection?

[PaulE]

The connection I made is directly to the 12v battery inside the vehicle located between the front seats and accessed from the middle row seats and the eyelets are connected to the battery posts bolts. I think you are talking about the jump start connection under the bonnet (the red connector under the fuse cover) with crocodile clips to this post and the black crocodile clip to a chassis ground (I use a grounded nut to the left of the red positive connector). I have read on previous posts that some members use these connectors to charge the 12v battery but it does mean having the bonnet up which is no problem if the van is garaged or you stay with it but could be an issue if raining. Not sure if this could be dangerous with possible petrol vapours under the bonnet, perhaps other members may comment. I will try and post a photo to explain. Cheers

 

[Jeza]

When you say you have anAlphard conversion, is that a camper? If so do you have a leisure battery with split charge relay? Is the 12v auxiliary battery still in the centre console or moved somewhere else, just making sure you are looking at the correct battery. 

[Borister]

Ah didn’t realise that it’s only the jump start connection under the bonnet. Yes the battery itself is under the drivers seat and quite fiddly to access. It’s a campervan conversion.

[Jeza]

That's the same configuration as mine with the aux battery under the drivers seat and leisure one in the console. There is a slight drain on the aux battery due to immobiliser, alarm, radio, various ecu's bit should not drain the battery in a few days. Try disconnecting the leisure battery to check the split charge relay is working correctly and not allowing the leisure side to take power from the aux battery. My aux battery is only a 45Ah AGM as it is squeezed under the seat.