Try checking the van battery without any load, having first put it on charge overnight, then leave the battery for 4 hours before checking the voltage, the battery should read over 12.60v for the next week, if it drops below 12.50v during this time, then I would say the battery is not holding it’s charge.
Also if the battery drops to below 12.20v during the above test, I would consider it to be at end of service.
Best to use a multimeter for the testing, even the cheap ones are quite accurate these days.
If the battery is over 5 years, then it is probably due for a change in any case.
Thank you, we have 2 leisure batteries on board,one was already in the van when we brought it and one new one we brought, also have a 100w solar panel,
It could just be a poor connection, however and more than likely its just not getting the power.
Have you tried to connect the tv to the battery (via fuse) the 12v sockets in caravans and campers often only have tiny wires and wont take the load a tv needs.
Check how thick the tv led is against the campers wires to the socket.
Ive a lead made up so my TV goes to the solar controller LVD. good sized wiring rather than the caravans pin thick wires
You need to take the right steps in the right order first before making up any leads up to run the TV on 12 volt power from the battery. It's a waste of time making alternative connections if the battery is knackered or needs recharging. Solar panels only work effectively in bright daylight hours so on dull days you can expect less charge and the fact that TV's consume a lot of power, if the battery is only partly charged then that part of the problem. First thing to do is to buy a voltmeter and do some testing, first at the battery and then it's a case of process of elimination. If you don't do that then it's just a complete guessing game what the problem is. Remember that any connections need to be fused otherwise you could end up needing a new telly as well as a battery.
No reason why you can't use your TV on 12 volt power, you just need a voltmeter to test the battery before hand to see if there is enough voltage to run it for several hours that's all. You can buy a voltmeter for under a tenner and if you are not sure how to use one just go on to YouTube for help.
If you have 2 leisure batteries you should always buy them as a pair, the problem could be with your older battery being faulty & dragging your new one down.
Quote: Originally posted by mark52 on 28/8/2020
If you have 2 leisure batteries you should always buy them as a pair, the problem could be with your older battery being faulty & dragging your new one down.
A very good point actually and never thought of that before but I suppose it's no different to a TV remote control handset where you replace all the batteries with new ones. If you put a new battery in with a part used one you are not going to receive 100% full power and prematurely reduce the life of the new one which is based on the same principal of the OP's query.
Current drawn by tv may be upto 3 to 6 amps especially with old CRT displays. This maybe enough to cause symptoms described. Another point is that the main wiring maybe undersized between the batteries and control unit exacerbating the symptoms. Since most on board charging systems give a continuous charge they do tend to be set on the low side. Should be at least 6mm squared cross section preferably 10mm squared (Electrical/battery installation ring terminals required due to size). A directly connected voltmeter via a line fuse and switch will give a monitoring function. A vehicle instrument voltmeter does have a fair consumption of 20 to 50mA so could show symptoms developing. Also the use of older technology such as incandescent spotlamps to give a monitoring load.