Low voltage while charging

abc123 · Jun 7, 2022

Hi,

I have a ocean 4motion 199 bhp 2019, and having problem with start battery and engine starts. Somehow my start battery is getting discharged.

Seeing strange things on the control panel. When I took the attached photo, before engine start, the leisure batteries was almost full, 12.7V. After engine start, and while driving, the panel stated that batteries was charging, but the voltage dropped to 12.4V? Have seen voltage as low as 12.1V while charging as well.

If i turn the lights on, it will start to charge at voltage above 13V.

While engine is on, and when its charging, shouldn't voltage always be 13V?

Is this some kind of leakage from start battery to leisure batteries?

yossarian · Jun 7, 2022

Leisure Battery Drain While Driving

I noticed while driving the other day that my console was saying a drain of between -5A and -8A for my leisure battery while I was driving, instead of positive amps from charging, as I would expect. I had nothing at all plugged into any of the sockets in the van (apart from my phone on the dash...

vwcaliforniaclub.com

abc123 · Jun 7, 2022

yossarian said:
Leisure Battery Drain While Driving

I noticed while driving the other day that my console was saying a drain of between -5A and -8A for my leisure battery while I was driving, instead of positive amps from charging, as I would expect. I had nothing at all plugged into any of the sockets in the van (apart from my phone on the dash...

vwcaliforniaclub.com

Hi, not the same thing. When the leisure battery back flow to the starter battery you get a negative readout on the display.

For me, there is a positive readout, boost charging but with low voltage.

flying banana · Jun 7, 2022

I've been wild camping 6 nights without running engine or hook up battery dropped to 10%. Driving has put it up to 80 % but the voltage is still low. Its normal. I will need a hook up Connect to sort mine out overnight. I have booked hook up for Friday. I will have been 10 days off grid and everything's run fine. I'm impressed

abc123 · Jun 8, 2022

flying banana said:
I've been wild camping 6 nights without running engine or hook up battery dropped to 10%. Driving has put it up to 80 % but the voltage is still low. Its normal. I will need a hook up Connect to sort mine out overnight. I have booked hook up for Friday. I will have been 10 days off grid and everything's run fine. I'm impressed

But the question is, what is your voltage during actual charging? When you see a positive amp readout on the panel, in my case boost charging, 20 amps with two arrows, combined with low voltage, 12.4V (attached picture in first post). I have not seen that before, and think something must be wrong?

yossarian · Jun 8, 2022

You have 4 voltage sources which are intermittently connected in parallel, one of which drops off line intermittently.

Battery range voltage accompanied by a positive charge suggests that:

Alternator is off line
Split charge relay is closed
Starter battery has a higher voltage than leisure batteries.

All the above are to be expected from time to time with the system as described.

flying banana · Jun 8, 2022

I

abc123 said:
But the question is, what is your voltage during actual charging? When you see a positive amp readout on the panel, in my case boost charging, 20 amps with two arrows, combined with low voltage, 12.4V (attached picture in first post). I have not seen that before, and think something must be wrong?

See that too. Its normal. Sometimes the leisure batteries drain into the start battery giving a negative amps when driving as the blue motion alternator goes offline. Its all normal I am now parked again. 3 days in and 11.6v but 70%. My voltage is getting low again