This article was supposed to go online months ago, but somehow I didn’t find the time.
We first became aware of this issue through the use of our auxiliary heating in the cab. The starter battery in the GC discharges extremely quickly, especially when using a parking heater. It happened to us that after 1 hour of heating the cab, the starter battery only had 60 percent of its charge left.
Vehicles that are parked for long periods of time and are not connected to the shore power also come into this problem zone. We have had countless messages by email or in the WhatsApp community. People have reported that they left their Cali parked outside the door over the winter, switched off the main battery switch in the rear and yet the car simply wouldn’t start in the spring.
The reason for this includes these great online services that are available in your Cali. For example, when you check the Volkswagen app, the vehicle first makes a call to VW’s own server. But that’s not all, all the control units in the vehicle go into standby mode when the vehicle is stationary for a longer period of time, but anyone who has been paying attention knows that standby also consumes electricity, and so it can happen that the starter battery is simply completely empty at some point, without you having moved your Cali a single meter.
Or you have a facelift with the new cockpit. I experienced it myself today: the vehicle is just parked on the side of the road, the control units are not shut down correctly, and after just one night of standing, the battery is only 30 percent full.
Have you installed solar in your Cali?
Does your Grand California have a solar panel? Then our Battery Maintainer is just the right gadget for you! It can be plugged into the fuse box of your Grand California in just two minutes. From then on, your starter battery is automatically charged via the solar panel on the roof – a function that is not available ex works!
As soon as the body battery reaches a state of charge of 80 %, the excess energy is used to constantly charge the starter battery. The maximum charging current is 3 A.
The Battery Maintainer can remain permanently in the vehicle – even during use or when the Grand California is connected to shore power. A single installation is all it takes!
We introduced this little gadget via our WhatsApp community and were completely surprised by the positive feedback and huge demand. We made 100 of them and what can we say, they were sold out within 2 weeks!
What you need to know
As mentioned above, our Battery Maintainer monitors the voltage of the body battery. If you have a lithium battery installed in your Cali, you can also use the Maintainer (we do this ourselves too), but the starter battery will then always be fully charged, regardless of whether the solar system is generating electricity or not. This is due to the higher voltage of the lithium battery. The Battery Maintainer therefore “thinks” that the body battery has more than 80 percent and charges the starter battery directly. This is not a problem, but it can lead to current being drawn from your lithium battery even though it is not yet full.
The Battery Maintainer theoretically also works with the facelift model, but unfortunately this still does not currently have a solar option. However, if you use a mobile solar panel or want the vehicle to charge the starter battery correctly even with shore power, the Maintainer could be your solution.
Fancy it?
We are currently producing new maintainers, again 100 pieces. You can pre-order these via our store. Please note, however, that delivery will take until the beginning of August 2025.
You can find the exact delivery time here:
One final word
A very personal final word is important to me. When we added the Maintainer to our store, we didn’t even advertise it and some people showered us with resentment and hatred.
Nobody has to buy anything from us, read this blog or like us.
Criticism was voiced:
“You could simply connect a cable from the solar regulator to the starter battery and you would have the same function.”
Of course you can do that! Can everyone do it? Does everyone want to? We didn’t want that and decided to go our own way. We don’t want to reinvent anything, but rather make “complex” issues accessible and, above all, solvable for everyone. The Maintainer is supplied ready to install and can be fitted by 99 percent of Cali drivers without any problems.
Or:
“The cut-off relay pulls itself in when solar charging, you don’t need the crap.”
This is technically correct, but the power of the solar panels is not sufficient to use the external charging function. If that were the case, nobody would have an empty starter battery despite the solar panels on the roof.
We have been sharing our experiences and gadgets with you since 2022. If you like it, you can buy it, if you don’t, don’t buy it. If you like our blog, you can read it, if you don’t, you don’t.
All our contributions are based on our experience and the things we like at the time of publication.
This might also interest you
Gadget Day – Battery Guard
Meet the Battery Guard – a handy Bluetooth module from Intact to monitor the charge level of your vehicle battery and take action in time!
Available at Jeff’s department store.
