Empty Engine Battery T5 and intelligent relay

[Hans6049]

I know that this topic has been discussed many times, but I have no clarity yet. The issue: I'm the happy owner of a VW Cali t5 (early version 2007). When camping we keep the leisure batteries powered up by hook up. However, the engine battery is separated and flattens within 2-3 days (because of radio, lights, sliding door etc.), which is very annoying if you want to move on. To solve this I sometimes use an additional Ctek charger for charging the engine battery when on hook-up.
Question: would it be possible to charge the engine battery via hook up by changing the relay under the driver seat with a Victron Energy Cyrix intelligent relay?
Looking forward to your input!

 

[andyinluton]

Could you not use a simple 12v lighter socket to lighter socket charger, one end powered by leisure battery & the other connected to engine battery.

 

[yossarian]

Could you not use a simple 12v lighter socket to lighter socket charger, one end powered by leisure battery & the other connected to engine battery.

Add about 1 Ohm resistor (5W or so) and no fear of excessive currents. Example

Batteries should be same chemistry and type. Ideally same brand and age.

 

[WelshGas]

I know that this topic has been discussed many times, but I have no clarity yet. The issue: I'm the happy owner of a VW Cali t5 (early version 2007). When camping we keep the leisure batteries powered up by hook up. However, the engine battery is separated and flattens within 2-3 days (because of radio, lights, sliding door etc.), which is very annoying if you want to move on. To solve this I sometimes use an additional Ctek charger for charging the engine battery when on hook-up.
Question: would it be possible to charge the engine battery via hook up by changing the relay under the driver seat with a Victron Energy Cyrix intelligent relay?
Looking forward to your input!

Yes, but that relay only works one-way, so would have to be removed or bypassed in some way to enable charging from the alternator when driving.

 

[WelshGas]

I know that this topic has been discussed many times, but I have no clarity yet. The issue: I'm the happy owner of a VW Cali t5 (early version 2007). When camping we keep the leisure batteries powered up by hook up. However, the engine battery is separated and flattens within 2-3 days (because of radio, lights, sliding door etc.), which is very annoying if you want to move on. To solve this I sometimes use an additional Ctek charger for charging the engine battery when on hook-up.
Question: would it be possible to charge the engine battery via hook up by changing the relay under the driver seat with a Victron Energy Cyrix intelligent relay?
Looking forward to your input!

Post 15 onwards.

Battery maintenance during the lock down

Hi all, looking for some advice on maintaining engine starter batteries for our Beach and also other car. I was thinking given the lock down I should get a battery trickle charger. Is it ok to use one of the cigar lighter adapters to charge the starter battery for the van and also my golf...

vwcaliforniaclub.com

 

[Hans6049]

Thanks for the replies. This brings me to another question: In what way has VW changed the technical design so that next versions of T5/T6 on hook up charge both leisure and engine battery?

 

[WelshGas]

Thanks for the replies. This brings me to another question: In what way has VW changed the technical design so that next versions of T5/T6 on hook up charge both leisure and engine battery?

No idea I'm afraid. On the T5.1 according to VW its not supposed to, but I, and others have proved the engine battery does get charged when the Leisure Batteries are fully charged by checking voltages on Mains hookup.

 

[splitmike]

Would it not be as easy to wire the stereo with a live from the leisure battery under the seat? this will help to stop the drain.
I personally take a Bluetooth speaker for use when camping that way it can be taken out into the awning too.