I have an Autotrail 630S on a 2001 Fiat Ducato 2.8JTD

The battery charging light is staying on. I have had the alternator tested and it has been verified as working. The alternator was removed and bench tested. It was replaced and all connections cleaned. The charging light is still on.

I suspect an earth problem, or a blown fuse. I am going to try and check both today.

My intention is to earth the engine block to the body using a standard jump lead.

Any advice and suggestions would be appreciated.

Thanks

Chay

Have you checked the voltage across the starter battery with engine stopped and running?
Get a digital voltmeter and you should have about 14volts (DC) between the +ve and -ve terminals of the battery if the alternator is charging when the engines is turning over at about 1500rpm. With the engine off, and after 5 minutes rest, the voltage across the battery should be in the region of 12.8 to 13.00 volts.
If you establish that the alternator is charging ok (you haven't said if the starter battery was going 'flat') then the problem lies in the charge lamp circuit which monitors the alternator differential output.
Poor earths cause all sorts of problems and well worthwhile taking the earth leads/straps off between the instrument binnacle etc and giving the connections a good clean. If you get the Fiat Elearn manual then you can see where the earth leads go and point you in the right direction before you start.
Good luck!

Thanks for the advice Toyogran.

The battery does appear to have gone flat.

The garage checked the voltage as you described. The alternator was not charging the battery, but the alternator had been checked on the bench as was OK.

I've removed the battery for charging, I've cleaned all the connections, checked the fuses and relays.
I suspected an earthing problem.

Again any further advice would be appreicated

Thanks

Chay

Check that you have battery voltage (when you have recharged it) on the D+ terminal on the alternator when the ignition key is on. You need a good voltage on this to 'excite' the alternator into charging when you initially start the engine. The charge light on the dash is supposed to indicate that there is voltage on D+ before you start. If there is no voltage (or insufficient) at D+ then the alternator will not charge.
Incidentally, the D+ terminal is used extensively on motorhomes for activating split charging for leisure batteries, fridges, retracting the access step etc. How did the problem originally manifest itself? Was it anything to do with a leisure battery circuit problem?
You are better off running a test wire from D+ (and the other connections if you want to establish that it is actually charging on the vehicle) on the alternator rather than trying to hold test leads on the terminals with engine running to keep the optimum number of fingers!
Inadequate, high resistance earths cause over 90% of all charging and electrical problems on older vehicles and are the first port of call in diagnostics. The only way to make sure they are working properly is to dismantle the connections, clean and reassemble. When you get them off check the actual leads for breaks, corrosion and high resistance with your digital meter.
Happy Easter!

There is an intermittent problem with the leisure battery electrics. Sometime
s when the lights or the water pump is switched on the voltage will flicker and or drop out completely.

On one occasion the power flickered and dropped, then it rose and I heard a click at the point it rose, the sound of a relay I suspect. My understanding was that the accomodation and the vehicle electrics were isolated from each other when the vehicle was not running.

The mechanic rigged up a test lead, I assume from the D+, to the vehicle battery positive, when tested that showed a charging voltage at the battery.

I have started work on the earh connections, but I'm not sure where they all are

Thanks

Chay

See if you can get hold of a wiring diagram from Autotrail which may throw some light on the connection between the leisure battery and the split charge circuit.
Try isolating completely the supply TO the leisure battery (it will be a hefty wire with an inline fuse somewhere).
See if that allows the alternator to charge the vehicle battery by checking the voltage across the terminals when the engine's running. If it does your problem is in the habitation electrics circuit.
Getting the Elearn manual will enable you to locate the earth leads and save lots of time guessing where they go. Do a search on this forum for help with downloading and burning a cd with the manual on it. I think it's the Elearn 244 one you need if yours is a JTD.
Good luck.

That's the battery checked now and it's OK

Now for some fault finding.

Problem appears to be solved.


As well as the vehicle battery charging problem, I also had a problem with the accommodation electrics. On checking the leisure battery I found the clamps were severely corroded. I replaced the clamps and cleaned up the battery posts.


I then noticed that the number plate lights were is a poor state. I removed them, cleaned them up, replaced the spade connectors and the bulbs.


Accommodation electrics problem appeared to be solved. Probably, hopefully, the battery terminals.


I then charged up the vehicle battery and got it tested, it was OK.


I installed the vehicle battery in the vehicle. There was an earth wire that had to be connected to the battery securing bolt. When connecting this I heard one of the two relays click. I tried again and heard a relay click. On checking it was on of the two relays, fridge and general power, that control the power to the accommodation. Again I cleaned everything and reconnected the earth. The relay activated again.


I started the vehicle and success and no charging light. YAHOO


One question springs to mind though:


1) Should a relay be active when the vehicle ignition is off?

Spoke too soon LOL

Anyway came home tonight checked the van again. Charger light coming on faintly. I identified the fridge relay and the split charge relay. I removed the fridge relay and checked that the fridge was not working. Still had the charging light glowing faintly.

Removed the split charge relay and the charging light went out. replaced it with a new relay and charging light glowed brightly. Tried the old relay and charging light returned to a faint glow. New relay tried again and the charging light glowed brightly. remove the relay and no charging light. I've found the source of the problem, but I'm not sure what is causing it.

Any help would be appreciatted.

Hi,
Can't think what the problem might be but can give a couple of pointers.

You mentioned in a previous post that one of your relays appears to be constantly live. The wiring diagram supplied by Autotrail for my van (2006 Cheyenne 696 on a 2.8JTD so the likelihood is that the wiring is similar) indicates that the solenoids in both split charge and fridge relays are energised by a feed from the alternator field circuit (D+?) As this is only live when ignition is switched on it appears that the whichever relay is constantly live is faulty or the wiring has developed a fault.

As you have now replaced the relay this would suggest the wiring is at fault. If you didn't get a wiring diagram with the van and wanted to have a look at mine I would be happy to scan it for you.

I think I have fixed the charging light problem, it appears to have been a wire which was earthed, or rather not earthed, to the battery tray. Think I’ve fixed it.

Now let’s see if I can get this right LOL

The split charge relay is a type B (see my diagram). The fridge relay was replaced recently and it is a type A. I’m not wondering if the repairer has replaced it with the wrong type. That would explain the permanently on status that I described in an earlier post. That would go some way to explaining the drain on the battery. I think both relays should be type B. I will obtain a type B relay and try it.

Again any advice appreciated.


I have attached diagrams of types A & B relays

I can confirm that the two relays on my van are of identical type.

The wiring diagram doesn't give terminal numbers so can't say whether they are your type 'A' or 'B' but the operating solenoid in the relay is connected between terminals 86 & 85 and when energised closes the contacts to link terminals 87 & 30.

HTH.

Hi,

I'm pretty sure they are both type B. The repairer replaced one of them with t a type A with is conntinually closed, this may have be the source of power drain from the vehicle battery. I have ordered two replacements. I suspect this is, at least partially, to blame for the charging light being illuminated. When I remove both relays the charging light goes off. Just wondering if there is something coming the wrong way, in relation to the leisure battery and habitation pwoer.

If you put relay A into connectors as per B then likely assuming 85 is earthed the relay will energise.....however is this supposed to happen (fridge / lights etc)
as it is a motorhome.

Can you follow the relay wiring (just pin 87) to see where it goes or if aftermarket fusebox the builders normally leave a diagram/guide sticker.

Type A does energise. I noticed that when connecting the vehicle battery, that's what alerted me to the potential problem. I assume that the relay should only energise when the vehicle ignition is on, otherwise the battery would be drained, which appears to be what is ahppening. I have removed the type A relay until I can get replacements

Thanks

Chay

I have purchased two type B relays which are only energised when the engine is running.

With the split charge and fridge relays removed the charging light is not illuminated.

Install either or both relays and the charging light comes on.

I note a considerable voltage drop across the live terminals of an empty relay holder when one relay is in place.

My next step is to purchase and replace the relay holders and the connection pins.

Any further suggestions are appreciatted

Thanks