Leisure battery probs/ fridge

Post by **kiwirob** » 07 Aug 2006, 21:50

Hi All
While checking fridge (only ice box working properly...turned upside down overnight as suggested on this forum...now working properly on 240v)... found that no voltage at 12volt fridge switch.
I found that 2 sets of wires coming from leisure battery...1 set to a relay with vehicle battery...showing voltage... other set disappearing forward...to dash(?£$*!) Having probs with pcb...need new one. Both sets earthed together...therefore earth ok?(if 1 is ok then both ok?)
Fuses at leisure batt ok. Don't know how to check for whether relay works although leisure batt not being charged by alternator...no change in voltage at leisure battery when engine running...13.8 at vehicle batt.
Stuck!
Would like to get fridge running on 12v.
Cheers
KR

Post by **Ivor Brownun** » 07 Aug 2006, 22:49

I've read on here that they only run off 12 volts with the engine running, this is because they draw too much current and the leisure battery would soon goes flat. If stuff is pre-chilled and you put a couple of those ice packs or litre bottles of frozen water in, it is suprising how long stuff will stay cool (4-6 hours) Then you can use gas or 240 volts. Most of these fridges work best on gas.

Post by **Mocki** » 08 Aug 2006, 06:58

take a look at the WiKi , the fridge shouldnt run off the leisure battery in any case, it should run direct from main battery via a switching relay that
ensures it only has power when the engine is running......

Website · Post by **dbroada** » 08 Aug 2006, 08:29

you can check if the relay is working by checking the voltages. Although there is a conventional way to wire them they do usually work "the other way round" so you may have to check a couple of time.

Coil wiring.
Pins 85 & 86. One of these should go to chassis, the other should be the trigger wire. The trigger wire should come from the alternator. With the engine switched off there should be no voltage on either of these pins. With the engine running there should be 12v+ on one, 0v on the other. If you have 12v on one pin then the relay is being activated, not that we have yet determined if it switches.

Switch wiring
pins 30 & 87. One goes to the main battery +ve, the other to the leisure battery +ve. Both of these should be fused at the battery end. Therefore you should see the LB voltage on one pin and the MB voltage on the other. If either shows 0v you have a blown fuse on that lead. Now start the engine and BOTH pins will show the alternator voltage. If only one side shows the alternator voltage then your relay isn't switching. It is more usual for a relay to fail closed so you are more likely to see (nearly) the voltage on the switch at all times. In both cases replace the relay.

Post by **kiwirob** » 08 Aug 2006, 14:19

Dave
I have done as you suggested.
1) Switching results:pos 30..main batt = main batt volt
87...leisure batt = leis batt volt
Both giving 13.3 or thereabouts..not exactly the same..from alt.
2) Coil results : pos 85 chassis = 0 volt
86 seems to bypass relay heading towards front of van comes back different colour (having trouble with instrument cluster and pcb anyway...needs replacing)
=0 volts engine off
= 13,63 v with engine on (Highest voltage measured.)
Would appreciate any thoughts...from anyone else as well.
Still no result from inboard flouro lights run on LB.
KR

Website · Post by **dbroada** » 08 Aug 2006, 15:39

if I understand your readings it certainly sounds like it is wired correctly. The slight difference between MB & LB when running can be due to internal resistance of the relay. I can see why you see LB voltage on relay at rest but not why you see alternator voltage at relay but not at battery when running. Unless somebody has fitted a diode (incorrectly) at some time.

What voltage are you getting on the leisure battery at the moment?

Post by **kiwirob** » 09 Aug 2006, 09:29

Dave
Thanks for all your help so far. Tha LB voltage is not good...8.5 -9.5...it seemed to charge a little with all the tinkering yesterday and so I put it on the charger last night...Charger says not fully charged yet...had this problem before...2 yrs old but only paid £20 at a stall at Newbury.
Rob

Website · Post by **dbroada** » 09 Aug 2006, 12:20

ah, could well be dead then. Lead acids don't like being left discharged for too long. A true deep cycle reacts more favorably to repeated discharge than a starter battery but neither really enjoy the experience.

Before putting the LB back in try to get its charge above 12v. Any less and you stand a good chance of blowing the fuses. When you have a charge imbalance between batteries the stronger battery will try to charge the weaker one resulting in a large current flow - far in excess of the alternator output - when the relay closes.

I would make sure the relay is switching as it should and be prepared to replace the battery. 12v is considered flat, and a full one is above 13v.

Post by **kiwirob** » 09 Aug 2006, 21:18

Any suggestions about where to buy a new LB? Halfords have 60amh for £50 and 75amh for £60?
KR

Website · Post by **dbroada** » 10 Aug 2006, 12:27

I'm in the fortunate position of not having had to replace my leisure battery yet. Fortunate as it is tiny, both electrically (about 20 AHr) and physically which means that it will fit under the passenger seat. And here is the problem. If your battery is under the seat the available space will limit the battery you can use. Measure it first AND DONT FORGET CLEARANCE ON THE POSITIVE TERMINAL. (That's why I removed the swivel from my seat). Heve a look in the wiki for the battery information.

Towsure had some cheap batteries (not sure if price reflects quality) but if you're not near one then Halfords may be a better bet. Not sure on Halfords pricing though.

Post by **kiwirob** » 10 Aug 2006, 13:52

Cheers for all that.
Rob