B2B Charger and Fiat - 'Check Glow Plugs' when starting

[rwg]

This is an interesting one...

First trip away in our (2021) Fiat PVC since fitting a B2B charger, and the van gives a 'Check Glow Plugs' warning when starting it if I have allowed the lithium battery to charge. The warning flashes for a few seconds, then the glow plug light flashes for about 30 seconds, then it clears.

If I block charging on the lithium battery via the App then it starts without giving the warning. This pattern seems to be 100% reliable so far.

The B2B is a Votronic 12-12-30, and is using the D+ line to control charging.

I am suspecting that the large initial current draw of the B2B charger is somehow messing with the way that the van monitors the glow plugs when starting.

Anyone else seen anything like this? I am tempted to try to put together a circuit that delays the D+ signal to the B2B by say 30 seconds.

thoughts?

cheers,

Robin

 

[rwg]

Well, I'm hoping that this little gadget will cure the problem

£5.69 off of Amazon (Amazon product ASIN B07SR4BX95).

It has various modes, one of which is to switch the relay on after a delay after power is applied. This should allow the B2B to come on 30 seconds or so after starting the engine rather than immediately.

They delay is configurable from <1s to 120s.

It should require 3 wires - D+ in, D+ out (delayed) and GND. It seems to draw about 5mA when connected and about 37mA when the relay turns on, so should be OK without additional power.

I will put it in a little box and try it out.

cheers,

Robin/

 

[rwg]

Well, I installed the circuit in the van today (made a little custom 3D printed box for it to go into - https://github.com/mrWheel/YAPP_Box - if anyone is into 3D printing).

The normal D+ (orange) and a ground connection come in at the bottom, powering the circuit and feeding the common connection of the relay. When the engine starts, the normal D+ goes to 12V and the circuit turns on. About 30s later the relay activates, sending 12V to the orange wire going out of the top, which goes to the B2B charger. I tested and watched it work - the lights on the B2B didn't come on until about 30s after starting the engine.

Hopefully will not see any more 'check glow plugs' messages and can consider the problem solved.

cheers,

Robin

 

[Googlebot]

Very useful info.

 

[Bobbydaisy]

Interesting, got a 2021 Ducato also same symptoms but no B2B fitted , starts ok etc but only began on our trip in November last and has been occurring ever since , going to book it in to dealership to investigate under warranty.

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[Lenny HB]

Interesting, got a 2021 Ducato also same symptoms but no B2B fitted , starts ok etc but only began on our trip in November last and has been occurring ever since , going to book it in to dealership to investigate under warranty.

Maybe the same problem is caused by the split charge relay, in very basic functional terms a B2B" is similar to a split charge relay, it puts a load on the alternator/starter battery to charge the leisure battery.
So it looks like it is not a Fiat fault so you may get charged by Fiat and have to reclaim it from Elddis.
I would pull the split charge relay fuse and see if the problem disappears, if it does it's an Elddis problem.

 

[arthur49]

Well, I installed the circuit in the van today (made a little custom 3D printed box for it to go into - https://github.com/mrWheel/YAPP_Box - if anyone is into 3D printing).

View attachment 714636
The normal D+ (orange) and a ground connection come in at the bottom, powering the circuit and feeding the common connection of the relay. When the engine starts, the normal D+ goes to 12V and the circuit turns on. About 30s later the relay activates, sending 12V to the orange wire going out of the top, which goes to the B2B charger. I tested and watched it work - the lights on the B2B didn't come on until about 30s after starting the engine.

Hopefully will not see any more 'check glow plugs' messages and can consider the problem solved.

cheers,

Robin

Thank you for this. My B2B is driven by an ignition signal, not D+, and I'd like to add delay before B2B fires up. This looks like an easy way ....

 

[Reallyretired]

I notice the relay contacts are only rated at 10A. Is it a 30A B2B?

 

[Lenny HB]

I notice the relay contacts are only rated at 10A. Is it a 30A B2B?

It is only switching the D+ which is only a few milliamps.

 

[rwg]

It is only switching the D+ which is only a few milliamps.

Yes, that's right - no real load there as it is just the control signal. Actually the worst thing about the little delay board is the green screw terminals which don't open very far at all. Not sure I would want to trust them at 10 amps... I struggled to get the orange wire in properly and it is only 1mm2 - certainly no chance to get two wires of that size into a single terminal, hence the need for the Wago connector as a junction block.

cheers,

Robin

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[Lenny HB]

Not sure I would want to trust them at 10 amps... I struggled to get the orange wire in properly and it is only 1mm2 - certainly no chance to get two wires of that size into a single terminal, hence the need for the Wago connector as a junction block.

After loosening the screw you have to flip the tab inside the terminal up with a small screwdriver it's surprising what you can get in those terminals.

 

[Reallyretired]

It is only switching the D+ which is only a few milliamps.

Silly me. Should read things proper.

 

[rwg]

I did try that - perhaps not applying enough force to properly move it (not sure where the breaking point would be). Will push harder next time.

cheers,

Robin

 

[Bobbydaisy]

Maybe the same problem is caused by the split charge relay, in very basic functional terms a B2B" is similar to a split charge relay, it puts a load on the alternator/starter battery to charge the leisure battery.
So it looks like it is not a Fiat fault so you may get charged by Fiat and have to reclaim it from Elddis.
I would pull the split charge relay fuse and see if the problem disappears, if it does it's an Elddis problem.

It’s a Smart Alternator fitted , does that make any difference ? Will try pulling the fuse in any case , thanks for the info , much appreciated.So it won’t be anything wrong with the glow plugs.

 

[rwg]

It’s a Smart Alternator fitted , does that make any difference ? Will try pulling the fuse in any case , thanks for the info , much appreciated.

Ours is smart alternator, which is why I installed the B2B. A split charge relay doesn't work properly with a smart alternator as when the alternator output drops you will end up with the leisure battery backfeeding the vehicle systems through the split charge relay Unfortunately van manufacturers mostly dont seem to care and keep on fitting the same kit they have for years.

For a smart alternator vehicle you really need a B2B, or perhaps some sort of diode pack to prevent the backfeed.

I looked at an interesting thing called an 'ideal diode' circuit which might do the trick - basically an electronic switch that you put in the cable between the two batteries and it will only switch on when the situation is right for the current to flow from the vehicle to the leisure battery.


cheers,

Robin

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[Lenny HB]

It’s a Smart Alternator fitted , does that make any difference ? Will try pulling the fuse in any case , thanks for the info , much appreciated.So it won’t be anything wrong with the glow plugs.

The problem appears to be with the smart alternators fitted.
With a smart alternator without a B2B the leisure battery will never charge very well, most converters fit a B2B with a smart alternator. If you definitely haven't got a B2B you need to fit one.

 

[Lenny HB]

Ours is smart alternator, which is why I installed the B2B. A split charge relay doesn't work properly with a smart alternator as when the alternator output drops you will end up with the leisure battery backfeeding the vehicle systems through the split charge relay Unfortunately van manufacturers mostly dont seem to care and keep on fitting the same kit they have for years.

For a smart alternator vehicle you really need a B2B, or perhaps some sort of diode pack to prevent the backfeed.

I looked at an interesting thing called an 'ideal diode' circuit which might do the trick - basically an electronic switch that you put in the cable between the two batteries and it will only switch on when the situation is right for the current to flow from the vehicle to the leisure battery.


cheers,

Robin

The problem with diodes is the volt drop across the diode will reduce the charge rate a bit of a waste of time.

 

[Insider]

I was of the understanding that any big name B2B would have it's own time delay on it so there is no charging done until 1 to 3 mins after start up. I have a Sterling and reasonably sure that is the case.

 

[rwg]

Hi,
the Votronic unit I have does have a delay when in 'voltage detection' mode (where it switches on based on the detected alternator voltage), but not in D+ mode. It would be better with one built in, but that's life... I chose it based on it's fairly compact size to fit into a small(ish) space.

cheers,

Robin

PS. Lenny HB - check out ideal diode circuits - they use high power mosfets to switch the flow on/off rather than a real diode, so the voltage drop is very low. This one reckons 40mV at 28A (Amazon product ASIN B07R6Q6LNF)

 

[headlight]

The manual for my recently fitted Sterling B2B states "may take up to 60 seconds to start charging"
In reality mine seems to start charging as soon as the engine is started.

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[Bobbydaisy]

The problem appears to be with the smart alternators fitted.
With a smart alternator without a B2B the leisure battery will never charge very well, most converters fit a B2B with a smart alternator. If you definitely haven't got a B2B you need to fit one.

Thanks will look into that ,Votronic and Sterling seem to be the ones to go for? Any diagrams to show how/where to fit it? there must be a load of vans out there with same issue but first I ve heard of any thread about it on this forum , you can’t miss the glow plug warning very easily

 

[activecampers]

This is an interesting one...

First trip away in our (2021) Fiat PVC since fitting a B2B charger, and the van gives a 'Check Glow Plugs' warning when starting it if I have allowed the lithium battery to charge. The warning flashes for a few seconds, then the glow plug light flashes for about 30 seconds, then it clears.

If I block charging on the lithium battery via the App then it starts without giving the warning. This pattern seems to be 100% reliable so far.

The B2B is a Votronic 12-12-30, and is using the D+ line to control charging.

I am suspecting that the large initial current draw of the B2B charger is somehow messing with the way that the van monitors the glow plugs when starting.

Anyone else seen anything like this? I am tempted to try to put together a circuit that delays the D+ signal to the B2B by say 30 seconds.

thoughts?

cheers,

Robin

I use a 12-12-30, set to "lithium", and using D+ to control charging on a 2020 160 ducato.

The D+ signal does not activate until engine is running and happy, so well after the glowpin startup sequence, and then (if needed) get +30A taken as expected.

Are you sure you are using a correct D+ signal and not IGN+ or KEY+ instead?

Where is your d+ signal taken from, and where is your +12v?

(The official D+ is not +12 as you'd expect, its 0v on running (grounded by ECU internals) and you have to reverse it with a relay (using D+ to earth a +12v input, usually key+ or ign+) to get +12v D+ signal for the B2B.)

 

[activecampers]

Thank you for this. My B2B is driven by an ignition signal, not D+, and I'd like to add delay before B2B fires up. This looks like an easy way ....

Why - that is not ideal at all - connecting +12v's together before engine is running has many unknowns especially for fussy electronics. But also, if your VB is almost flat, putting the key in and activating ignition could connect both the batteries together (well, it would with a basic relay, but could also with a B2B that is doing magic with the voltage, who knows) - but then starting the engine and pulling +100A from the VB would also suck the load from the LBs (again, depends on how B2B works) with undesired consequences.

(My first pro van was wired this way, and, well, after many years of no issues I hit such scenario and there was lots of smoke and melted plastic! Lets just say I rewired it with a bit more thought..... Pros eh?)

 

[rwg]

I use a 12-12-30, set to "lithium", and using D+ to control charging on a 2020 160 ducato.

The D+ signal does not activate until engine is running and happy, so well after the glowpin startup sequence, and then (if needed) get +30A taken as expected.

Are you sure you are using a correct D+ signal and not IGN+ or KEY+ instead?

Where is your d+ signal taken from, and where is your +12v?

(The official D+ is not +12 as you'd expect, its 0v on running (grounded by ECU internals) and you have to reverse it with a relay (using D+ to earth a +12v input, usually key+ or ign+) to get +12v D+ signal for the B2B.)

I'm using the D+ signal that comes from the Sargent interface box that is in the floor behind the driver's seat and connects to the van electrics there. It also does things like switch off the van electrics when you start the engine, retract the step and switch on the 12V to the fridge. Quite what the Sargent box does to generate it, I can't say... The step certainly comes straight in when you start the engine, so there is no delay.

I did test it when I was planning the B2B install, and I am 99% sure I checked it was 0V with the ignition key turned one click and only went to 12V when the engine was running. I will check again in the morning.

cheers,

Robin

 

[activecampers]

I'm using the D+ signal that comes from the Sargent interface box that is in the floor behind the driver's seat and connects to the van electrics there. It also does things like switch off the van electrics when you start the engine, retract the step and switch on the 12V to the fridge. Quite what the Sargent box does to generate it, I can't say... The step certainly comes straight in when you start the engine, so there is no delay.

I did test it when I was planning the B2B install, and I am 99% sure I checked it was 0V with the ignition key turned one click and only went to 12V when the engine was running. I will check again in the morning.

cheers,

Robin

Ah, yeah can't comment if it connects from the Sargent - sorry. But can say my voltronic 121230 is wired to the (correct) D+ signal and I've not seen the issue.
So yeah, be good to know if its key+ or ign+ that they use just for other people searching the thread. Your timer is a good plan B.

FYI the ECU D+ signal isn't just engine running, but also "engine should be running" - so is active (0v) when engine starts, but also remains active if the engine stops during automatic stop-start - but does drop out if stalled. It becomes active only when engine is running (a second or two) - not during engine cranking.

Look forward to your answer

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[arthur49]

Why - that is not ideal at all - connecting +12v's together before engine is running has many unknowns especially for fussy electronics. But also, if your VB is almost flat, putting the key in and activating ignition could connect both the batteries together (well, it would with a basic relay, but could also with a B2B that is doing magic with the voltage, who knows) - but then starting the engine and pulling +100A from the VB would also suck the load from the LBs (again, depends on how B2B works) with undesired consequences.

(My first pro van was wired this way, and, well, after many years of no issues I hit such scenario and there was lots of smoke and melted plastic! Lets just say I rewired it with a bit more thought..... Pros eh?)

Which is exactly why I want to have a 30 sec delay!
D+ has failed for unknown reason at present.
Work around is ignition on signal easily picked up, used to drive a small NO relay (with diode) to replace D+ supply B2B.
Votronic 50A B2B and currently using Mode 4 which, from Votronic manual:
"4. Activation of the Charging Converter by Control Signal "D+" or ignition "Kl.15". This operating mode is particularly provided for EURO standard 6, 6+ vehicles with intelligent generators, energy management, start/stop automatics, strongly varying voltage of generator/starter battery during energy recovery etc. Generally recommended for operation with electroblock EBL, EVS. The start sensor cables "Vs- and Vs+" are not required, if the values in the tables 1 for "Cable Length "+ START" are only used to approx. 3/4. If the cables are long (losses), these cables are, however, advantageous for full charging capacity. Control the control input "D+" either with KL.15 (ignition ON) or more safely connect it to D+ of the vehicle (generator "active"), since in case of a continuous signal (ignition ON) without running engine the starter battery can be strongly discharged!"

 

[Bobbydaisy]

Jeez this has got very technical very quick , haven’t a scooby what you are going on about but my glow plug light still comes on ….. near the start of the thread

 

[activecampers]

Jeez this has got very technical very quick , haven’t a scooby what you are going on about but my glow plug light still comes on ….. near the start of the thread

lol.
With smart alternator, you would be better off with B2B as the voltage given out by a smart alternator is too high (at times) to charge LB's safely - and could fry/damage batteries unless other systems are in place.

But, if you have simple split charge relay and thats the question asked, is that voltage sensitive or just turned on by "ignition" or "key". If simple and turned on via ignition or key, then you (probably) have the same issues as the OP, and the same solution mentioned (timer delay) would help you out.

That said, the timer delay is a good plan B - but isn't the gold standard, which is to use the correct D+ signal, but if you don't have a converters socket its hard to find/use


Caveat: The devil is in the detail!!!! If you dont know exactly the setup you have, its hard for anyone to give you an exact answer. Lots of options, lots of variables, and lots of terms/words used rightly and wrongly - so if you don't know, best to get someone who does to check. Also, has rwg confirmed his timer has fixed his issue?

 

[rwg]

Ah, yeah can't comment if it connects from the Sargent - sorry. But can say my voltronic 121230 is wired to the (correct) D+ signal and I've not seen the issue.
So yeah, be good to know if its key+ or ign+ that they use just for other people searching the thread. Your timer is a good plan B.

FYI the ECU D+ signal isn't just engine running, but also "engine should be running" - so is active (0v) when engine starts, but also remains active if the engine stops during automatic stop-start - but does drop out if stalled. It becomes active only when engine is running (a second or two) - not during engine cranking.

Look forward to your answer

Ok, so I checked this morning and the things that happen off of the Sargent D+ (step being brought in, van 12V power being switched off and now the B2B) do not happen when you just turn the key one turn to put the ignition on, only when the engine starts running.

Also, if you turn the fridge to 12V then it beeps frantically when you stop the engine, but not when stop/start stops the engine, so the D+ behaves as it should - staying on during stop/start engine stops.

For reference, I found this circuit diagram, which I think is someone's work at decoding the circuit of the Sargent van interface board : https://autotrailusers.nz/ForumFiles/1012/Sargents EM40 interface circui Revised.pdf - it looks like the combination of IGN high and DNeg low triggers relay 2, which then puts the output D+ to 12V

We are off on a trip this weekend, so I will see if we get any check glow plug messages now the delay is wired in. It could all have been coincidence with it starting the first trip after installing the B2B and seeming not to happen when the battery was not allowed to charge.

I have however been wondering about how the 'check glow plug' warning would be implemented... Vehicle manufacturers love putting one part to multiple uses (like tire pressure monitoring using the ABS rotation sensors). If you wanted to add a glow plug diagnostic without any extra parts, maybe you use the current measurement that you already have at the battery -ve terminal in a stop/start system, and warn if the current change is outside some accepted range when the glow plugs go on/off? Pure speculation on my part - it would be interesting to know how it really works...

cheers,

Robin

 

[arthur49]

Well, I installed the circuit in the van today (made a little custom 3D printed box for it to go into - https://github.com/mrWheel/YAPP_Box - if anyone is into 3D printing).

View attachment 714636
The normal D+ (orange) and a ground connection come in at the bottom, powering the circuit and feeding the common connection of the relay. When the engine starts, the normal D+ goes to 12V and the circuit turns on. About 30s later the relay activates, sending 12V to the orange wire going out of the top, which goes to the B2B charger. I tested and watched it work - the lights on the B2B didn't come on until about 30s after starting the engine.

Hopefully will not see any more 'check glow plugs' messages and can consider the problem solved.

cheers,

Robin

Well thank you again. I ordered yesterday, arrived this morning, wired in (but not fully installed) and its working a treat!
Pity there's no instructions ...

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