landroversforever Posted July 12, 2011 Share Posted July 12, 2011 Firstly apologies for the layout... I'm just going to 'splurge' before I go to bed, and also sorry if I've missed anything crucial. My electrical System Twin batteries Red top running the starter motor (roughly 12v without engine running) Numax running everything but the starter. X Charge Problems left a work site in oxford, put lights on as its getting dim. noticed speedo not working noticed rev counter not working sidelights working headlights not working, nor main beam rev counter works when all lights off as does speedo speedo works (moves) when only the sidelights are on no hazards no visible indicators from in the cab (very dim on warning panel) while driving, tried main beam (not working), then try my ARB compressor, the truck slowly dies but engine still moving (I think the stop solenoid was devoid of power) truck started again as it was effectively bumped. Interestingly, the trailer light warning thingy watsit seems to work better during all this. My brief findings lights and everything seem to function OK when engine is off very low voltage on the Numax (roughly 9.5-10v), but the Optima is ok. All fuses intact Truck wont start unless jumping from its self. Thoughts - could be any combination...or something else... Alternator isn't charging properly Battery isn't holding charge (numax was new a couple of months ago) Wiring fault? (Earth?) X Charge isnt working? (I'm sure Si said it has an X Charge, but I cant remember ) Quote Link to comment Share on other sites More sharing options...
UdderlyOffroad Posted July 13, 2011 Share Posted July 13, 2011 Alternator isn't charging properly Wiring fault? (Earth?) Those are the first two to check. Are you getting 14.4v or so with t'engine running at both battery terminals (with split charge engaged?). Whilst you've got the seatbox lid up, take the opportunity to clean the earths too... Red top running the starter motor (roughly 12v without engine running) Numax running everything but the starter. Whem you say everything, do you literally mean all the other vehicle circuits (headlamps, indicators etc) or just auxiliary functions (worklights, fridge etc) on a separate fusebox? If the former, how have you managed this? My (limited) electrical trainings tells me that you would need a seperate, dedicated negative (not the chassis) for at least one of the battery systems to prevent problems with the batteries trying to 'balance' each other, which could be the problem here, if the charging system is fine. I.e. do you have a dedicated negative cable from the starter motor to the Red top? Disclaimer: I am by no means a sparkie, and very much an armchair split-charge general (in that mine hasn't moved out of bag-of-fag-packet-sketch stage yet). Quote Link to comment Share on other sites More sharing options...
landroversforever Posted July 13, 2011 Author Share Posted July 13, 2011 Firstly my electrical knowlege is also very limited! I cant remember, but I dont think I checked the charging voltage of the batteries. Everything but the starter is on the Numax. Both of the negative terminals are linked, surely they would need the positive's linked to try and balance each other? I'm not sure off the top of my head if the starter has a dedicated earth? The split charge was set up by the P.O, not sure for how long ago but it has always worked fine for me. I replaced a yellow top, but that was in the starter battery postion. Talking to some people at work, they think the symptoms point to a failed split charge relay. Therefore the battery not being charged. My thoughts are that something has failed as this just happened, its not been slowly getting worse. Anyone know how to check if the X charge relay has failed? Quote Link to comment Share on other sites More sharing options...
CwazyWabbit Posted July 13, 2011 Share Posted July 13, 2011 (edited) The X charge relay should switch when the alternator warning light goes off, fitting instructions are here http://www.x-eng.co.uk/Instructions/X-Charge.pdf and show how it's wired up. If you diconnect the high current connections of the relay and connect a continuity tester accross them you should see no continuity, start the engine and when the light goes out there should be continuity, anything else would indicate a 'problem'. Don't forget to insulate the high current wires when they are disconnected! HTH Edited because I can't spell Edited July 13, 2011 by CwazyWabbit Quote Link to comment Share on other sites More sharing options...
UdderlyOffroad Posted July 13, 2011 Share Posted July 13, 2011 I cant remember, but I dont think I checked the charging voltage of the batteries. Anyone know how to check if the X charge relay has failed? Just that; Check that you've got 14.4v at the terminals on both the red top and the Numax with the engine running. That way you know your split charge is working and that the alternator is charging as it should. To double check, Crazywabbit’s test will confirm all is healthy with the X-charge unit itself. Quote Link to comment Share on other sites More sharing options...
CwazyWabbit Posted July 13, 2011 Share Posted July 13, 2011 I just re-read your original post and ... ... [*]Red top running the starter motor (roughly 12v without engine running) [*]Numax running everything but the starter. [*]while driving, tried main beam (not working), then try my ARB compressor, the truck slowly dies but engine still moving (I think the stop solenoid was devoid of power) truck started again as it was effectively bumped. [*]lights and everything seem to function OK when engine is off [*]very low voltage on the Numax (roughly 9.5-10v), but the Optima is ok. [*]Truck wont start unless jumping from its self. Are you certain it's the Numax that is low voltage and runs everything but the starter? If the main battery (the optima) was low that would explain why you need to jump the batteries to start and why everything else works better when the engine isn't running as the relay will not be connecting the batteries and causing the voltage to be dragged down. Quote Link to comment Share on other sites More sharing options...
landroversforever Posted July 13, 2011 Author Share Posted July 13, 2011 Yeah. The when I had battery trouble before I traced it back to from the starter to the red top. without the engine running, the red top shows a much better voltage than the numax. Also, the numax's indicator isnt green anymore (implying it needs a charge). I will check the voltages with the engine running when I get home. Quote Link to comment Share on other sites More sharing options...
CwazyWabbit Posted July 13, 2011 Share Posted July 13, 2011 Yeah. The when I had battery trouble before I traced it back to from the starter to the red top. without the engine running, the red top shows a much better voltage than the numax. Also, the numax's indicator isnt green anymore (implying it needs a charge). I will check the voltages with the engine running when I get home. Just dawned on me, the power for the starter solenoid (not the actual starter) could be coming from the flat battery hence why you have to jump it. That would then explain the symptoms for starting as the low voltage wouldn't be enough to switch the solenoid. A faulty relay could explain the uncharged Numax but I'm still at a loss to explain why other things work better with the engine off. Quote Link to comment Share on other sites More sharing options...
ARMYBOB Posted July 13, 2011 Share Posted July 13, 2011 to check your relay you dont need to disconnect anything, using a multi meter set to volts, black wire to a good earth, check both sides of the relay(the heavy duty connectors) it should read the same both sides if the relay is working ie the contacts are closed, if you dont get this and the relay has not engaged it may be at fault but you need to check the supply to the relay on the small terminals, you should have battery/alternator voltage on one of the terminals the relay is bascially a remote switch, 12v switches it on which allows the heavy duty contacts to close. i dont get why you have just the starter on one battery and everything else on the other? or am i being nieve on dual battery set ups, i thought the idea was to run a main battery as normal, ie for the car and functions, then run your second for the auxilliary functions, compressors, fridges, work lights, winches etc that way you dont drain your main vehicle battery when using all your extras and should your main battery run flat for some reason, you can jump start yourself from the second battery. reading yoiur symptoms it does seem the numax isnt charging, when self jumping do all the missing functions work ie lights, speedo etc, remeber self jumping works both ways and your red top is probably boosting the numax, i would have a look at how you have everything wired up seems your red top is wasted on just starting to me i have a wee bit experience with electrics/electronics, actually im an electronics technician and have been fixing tanks for 14 years, electgrics is my bread and butter. not boasting just background info Quote Link to comment Share on other sites More sharing options...
landroversforever Posted July 13, 2011 Author Share Posted July 13, 2011 More things to try when I get home . Thank you everyone so far! The battery layout is as the P.O. had it. I could be wrong, but I think it was so the starter wouldn't be without power. Also it may have been something to do with having a winch. In all honesty, I have no idea... Yes, everything seems to work correctly when self jumping. Not tried the actual speedo reading though as to self jump I need the door open . I think the truck is throwing a paddy as it isn't being taken to billing this year!! Quote Link to comment Share on other sites More sharing options...
Guest Posted July 13, 2011 Share Posted July 13, 2011 Ross, I would say you have one of Three problems: 1, Your alternator is not charging 1a duff alternator 1b bad earth or cable 2, Your battery is duff and not holding charge 3, Your split charge is broken From what you have posted I think I can figure out your electrical system and correct me if I am wrong but: Your alternator and starter motor cables are connected to the first battery, normaly all of the other main circuits will also be connected to this battery although indicate otherwise you then have a x-charge (or split charger) which charges the your second battery, normally this will power the aux circuits and the winch etc but you seem to think that this supplies the vehicles fuse box and all associated circuits are connected to this second battery. Although difficult to say without seeing it I would say it sounds like the first battery is not charging/duff and that as you are not using the aux equipment winch etc the second battery has enough charge to jump the first and that it is set up as a normal system not as you suggest. So now to go through the fault finding: 1 Alternator you should be getting about 14v on the big cable going to the battery once the engine is running if you don't have this then you need to start fault finding the alternator circuit. 2 If you are getting around 14v but when you switch the engine off the voltage drops to 12v or lower the battery could be duff, easiest way to check this is to stick it on a charger overnight and check the voltage before and after you get to work. 3 The reason you have a split charge rather than just wiring the two batteries together is to prevent the total discharge of your starter battery when winching or if you left the lights on/fridge drained the battery etc. Most split charges work via a voltage sensitive relay relying on the primary battery to reach a 'charged voltage' around 14.3v they will then turn on charging the second battery as the primary battery will then be full!! If the first battery is not reaching this voltage duff/not charging then the split charge will not active anyway and the two batteries will not charge, the other advantage with a real split charge system is that they also normally have diodes to prevent the second battery trying to equalise with the first thus the batteries don't 'eat each other' as are isolated when not charging. I doubt that the split charger will be at fault however the easiest way to test this would be to put a jump lead between the positives once you have charged them/whilst charging them make sure they don't touch the body etc but then you can test the voltage at the end of a run again to see if the second battery is now getting a charge however as above if the primary battery is not receiving a charge in the first place the second battery is not meant to charge. Jason. If you want to talk through it give me a call. Quote Link to comment Share on other sites More sharing options...
landroversforever Posted July 13, 2011 Author Share Posted July 13, 2011 Thank you for the natter Jason . Bear in mind with the Numax, it has been on charge over night. Red top - Engine running = 14.6v Numax - Engine running = 12.86v Red top - Engine off = 12.87v Numax - engine off = 12.95v Voltage on the Red top jumps right up as soon as the engine is started, no response straight away on the numax. Left for 30mins with the engine running, it still didn't start charging. Numax: Engine off = 12.83v Engine running with batteries jumped = 14.09v (Max 14.10v) Engine running for 15-20mins still jumped, then turned off = 13.20v I think this points to the X charge relay being duff? Quote Link to comment Share on other sites More sharing options...
ARMYBOB Posted July 13, 2011 Share Posted July 13, 2011 looks like your relay aint working to me, by jumping with the cable you removed the relay did you check the relay as i suggested? reckon your alt is fine, but your numax is not being charged, your jump experiment proved this earths are always possible duff battery, a maybe after you charged it overnight didit start fine? and did all the functions work? not trying to step on jasons toes here he seems to know split charging systems well Quote Link to comment Share on other sites More sharing options...
landroversforever Posted July 13, 2011 Author Share Posted July 13, 2011 Sorry Armybob, I havent tried that, I tried the easy method as the being the electrical dummy here I thought it best . Plus, the relay is buried and inaccessible without taking the batteries out. With the charged battery everything worked great. All lights and no dimming of gauges with the lights on etc. . I will get a new relay at the show on friday Quote Link to comment Share on other sites More sharing options...
Guest Posted July 13, 2011 Share Posted July 13, 2011 (edited) looks like your relay aint working to me, by jumping with the cable you removed the relay did you check the relay as i suggested? reckon your alt is fine, but your numax is not being charged, your jump experiment proved this earths are always possible duff battery, a maybe after you charged it overnight didit start fine? and did all the functions work? not trying to step on jasons toes here he seems to know split charging systems well No offence taken Bob, that's one of the great things about this forum everyone can chuck in their without to much fear of being ridiculed (not saying that if your statement is just daft and you are know people won't take the mickey!! would say it was the split charge system however as Bob say's Ross it may not be the actually system but something as simple as a bad earth to the relay that is causing the issue, you need to start buzzing out the circuits with your original description of the way the circuits are connected the battery voltage sounds about right so I would park the duff battery (for now) you should try the jump lead thing next and see how that goes. Edited July 13, 2011 by western edited to one type of font & size, so it's easier to read. Quote Link to comment Share on other sites More sharing options...
landroversforever Posted July 13, 2011 Author Share Posted July 13, 2011 OK, I will unbolt the relay from in the battery box and see if I can get it a bit more accessible. Did you mean 'park'? Jump lead thing... was that disconnecting the relay, measure the voltage on the battery and then do the same after a drive? (sorry if I've forgotten...I fell asleep in front of top gear Quote Link to comment Share on other sites More sharing options...
Guest Posted July 13, 2011 Share Posted July 13, 2011 OK, I will unbolt the relay from in the battery box and see if I can get it a bit more accessible. Did you mean 'park'? Jump lead thing... was that disconnecting the relay, measure the voltage on the battery and then do the same after a drive? (sorry if I've forgotten...I fell asleep in front of top gear You are going to have to disconnect the x-charge system to check it first before you get a new one otherwise you may just be replacing something that is not faulty if for example the negative has become disconnected then the relay won't work anyway. Sorry by 'park' I meant discount it for now but as you have not tested it don't discount it from the fault resolution but park that avenue of enquiry for now. The jump lead thing is as above remove the split charge system put a jump lead between the batteries and check the voltage after a run if it is taking holding a charge you know things are good, you will also need to run the truck with it until you either fix/replace the x-charge. Jason. Quote Link to comment Share on other sites More sharing options...
landroversforever Posted July 13, 2011 Author Share Posted July 13, 2011 I assume it does need to be a run and not just sat with the engine running? I will look a bit more closely at the relay tomorrow . Quote Link to comment Share on other sites More sharing options...
CwazyWabbit Posted July 13, 2011 Share Posted July 13, 2011 Out of curiosity what is the advantage of having just the starter on one battery? It doesn't allow the vehicle to start when the 'aux' battery is flat, which I thought was one of the main points of having twin batteries. Quote Link to comment Share on other sites More sharing options...
landroversforever Posted July 13, 2011 Author Share Posted July 13, 2011 After this episode... I'm not sure what the advantage of this set-up is. If It was me adding a second battery I wouldn't do it this way Quote Link to comment Share on other sites More sharing options...
western Posted July 13, 2011 Share Posted July 13, 2011 Out of curiosity what is the advantage of having just the starter on one battery? It doesn't allow the vehicle to start when the 'aux' battery is flat, which I thought was one of the main points of having twin batteries. if a winch is fitted & used by having a seperate start battery the engine can still be started even if the winch/2nd battery is flat, on my 110 my winch has it's own battery fed via a LR split charge relay system. vehicle/start battery runs everything else & I've fitted a isolator switch as a internal jump start Quote Link to comment Share on other sites More sharing options...
CwazyWabbit Posted July 13, 2011 Share Posted July 13, 2011 if a winch is fitted & used by having a seperate start battery the engine can still be started even if the winch/2nd battery is flat, on my 110 my winch has it's own battery fed via a LR split charge relay system. vehicle/start battery runs everything else & I've fitted a isolator switch as a internal jump start That's the way I thought they were supposed to work but the original owner of Ross's Landy has only the starter wired to the main battery and everything else to the 2nd battery which in my mind seems to defeat the point somewhat as it won't start when the second battery is flat, I was just wondering if there was any reason for this other than a mistake. Quote Link to comment Share on other sites More sharing options...
Guest Posted July 13, 2011 Share Posted July 13, 2011 That's the way I thought they were supposed to work but the original owner of Ross's Landy has only the starter wired to the main battery and everything else to the 2nd battery which in my mind seems to defeat the point somewhat as it won't start when the second battery is flat, I was just wondering if there was any reason for this other than a mistake. I am sure that Simon had a reason behind it!! Ross have you checked with Si as to how he wired it? Jason. Quote Link to comment Share on other sites More sharing options...
CwazyWabbit Posted July 14, 2011 Share Posted July 14, 2011 I didn't know it was Simon, in which case there is bound to be some cunning logic as to the wiring design Quote Link to comment Share on other sites More sharing options...
UdderlyOffroad Posted July 14, 2011 Share Posted July 14, 2011 That's the way I thought they were supposed to work but the original owner of Ross's Landy has only the starter wired to the main battery and everything else to the 2nd battery which in my mind seems to defeat the point somewhat as it won't start when the second battery is flat, I was just wondering if there was any reason for this other than a mistake. The only thing I can think is that it prevents you from being unable to start the truck should you accidentally leave the headlights on or the door open. (Not withstanding the headlamp kill relay recently discussed in this forum). To my mind, this could still cause funny effects, however, as you need a healthy (but admittedly not much current) 12v from the other battery to drive the coil (or fuel stop solenoid in a diesel). The good thing is though, that if Ross doesn't like the setup, it being a Landie he can change it back to a more 'normal' split charge arrangement (1st battery to run the vehicle, 2nd battery for additional functions and/or winch) with relative ease! Quote Link to comment Share on other sites More sharing options...
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