Fiat Smart Alternator problems

Are you sure? Its many years since I studied it, but I was taught that even multigrades get thicker when cold. They just don't get as thick as single grades do.
So at a certain cold temperature the 75/90 would be as thick as a 75w would be at that temperature
And at a certain hot temperature the 75/90 would be as thick as a 90w would be at that temperature
But it would still be thicker when cold
It may apear to be thicker but all on utube to see what happens, low number will flow in cold weather and first starts in the morning where 90% of wear happens to engines, a 10/40 semi is a good all rounder, but do use what the makers say for out climate.
OIl flow -20c
oil minus 20.png
 
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Sorry I should have said - my secondary batteries are not leisure batteries - just 4 of these 019 https://www.tayna.co.uk/car-batteries/varta/h3/
The yellow light comes with info on the display panel saying start/stop inoperative - which potentially affects the emissions, so I guess thats an MOT fail
My understanding is the computer has to work out whether the battery is sufficiently charged for start stop operation, and the extra batteries have made it unable to calculate whats gone in and out through the O/E current sensor on the main battery.
Fair point that the extra load may shortern the life of the alternator. Which is presumably why Fiat say don't have a seondary battery bigger than 20ah. Which I think is absurd for a vehicle they market as suitable for motorhomes and just an attempt to evade responsibility.
But maybe shorterning the life of the alternator is the price I have to pay because I can't manage with 20ah.
I understand that the B2B charger would charge the secondary batteries more fully (if it will work with 400ah) but with plenty of spare capacity I don't need to charge them fully everytime.
NOT keeping LA batteries fully charged will shorten their life span dramatically, don't do it! You'd have arguably have been better fitting fewer batteries and having them sitting at a higher charge level.
If you're going to leave batteries standing in an under charged state for any length of time then you need Lead carbon which are OK to be left sitting down to about 50% discharge.
With well over £400 spent on LA batteries I think you should get a B2B fitted ASAP personally.
 
NOT keeping LA batteries fully charged will shorten their life span dramatically, don't do it! You'd have arguably have been better fitting fewer batteries and having them sitting at a higher charge level.
If you're going to leave batteries standing in an under charged state for any length of time then you need Lead carbon which are OK to be left sitting down to about 50% discharge.
With well over £400 spent on LA batteries I think you should get a B2B fitted ASAP personally.
Hi
I replied earlier but my posts are held 'awaiting moderator approval', presumably because I am a new member?
so by the time my posts are published the conversation has moved on, and my comment missed.

What prompted me to join and post was the question of how to test the alternator didn't seem to have been answered. So I just wanted to say you can do it by creating the conditions where its being charged by regenerative braking - when I do that the voltage goes up to somehing approaching 15 volts (unless all batteries are fully charged) - proving the alternator is OK. I hope that answers the OP's question.

Yes, the batteries are not usually fully charged, they are connected in parallel with the main battery so they only get fully charged when decelerating in gear (slowing down or going downhill) with regenerative braking. But, like the main battery, they don't go flat - if they did the main battery would be flat too (since they connect in parallel) and the engine wouldn't start. But there has always been plenty of power to start the engine.
I'm not sure of the exact percentages, but its something like 80% charged when the engine is running, with regenerative braking providing the top up as and when it is working. I have a voltmeter connected to the secondary batteries, and the main batteries, so I can keep an eye on both. With 400ah of secondary battery capacity I don't need them fully charged every time I stop.

I can see this wouldnt do for a professional installation, because you need something you can fit and forget. If you did it like that the customer would bring it back saying the start stop was not working (which I don't need anyway). Although I don't know whether fitting a B2B charger would solve that problem.

Could I spend £600 on a B2B charger and still have the start stop inoperative (engine management) warnng light coming on?

Other than that it seems to be more environmentally friendly than a B2B charger set up. The B2B charger wouldn't make use of regenerative braking.

The B2B charger would also consume so much extra power it needs a fan to cool it down - Increasing the work of the alternator and possibly shortening its life?
 
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I have a voltmeter connected to the secondary batteries, and the main batteries, so I can keep an eye on both.
The Voltage is not the most important bit, you need to know how many Amps are going into and out of the batteries. At 15V and an unrestricted connection to your 400Ah battery you might be demanding too much of your alternator, hence Fiat’s 20% limit which you are greatly exceeding. At the lower voltage there is probably no Amps going in, they may even be flowing out.
The B2B charger would also consume so much extra power it needs a fan to cool it down - Increasing the work of the alternator and possibly shortening its life?
There are B2B chargers available with 92-98% efficiency. Yes a little bit of power will be lost to heat when using one but nothing significant. One of the principle purposes of a B2B is to protect the alternator, which is especially important with smart alternators. You current arrangement poses a far greater risk to life of your alternator, a properly sized B2B would protect it from working outside it’s limits.
 
You probably have a ‘smart ‘ alternator and it will charge or not charge with an alarming inconsistency. It all depends on the voltages and whether you are running down and braking as they slow the engine like a brake absorbing a good deal of power.
 
Hi
I replied earlier but my posts are held 'awaiting moderator approval', presumably because I am a new member?
so by the time my posts are published the conversation has moved on, and my comment missed.

What prompted me to join and post was the question of how to test the alternator didn't seem to have been answered. So I just wanted to say you can do it by creating the conditions where its being charged by regenerative braking - when I do that the voltage goes up to somehing approaching 15 volts (unless all batteries are fully charged) - proving the alternator is OK. I hope that answers the OP's question.

Yes, the batteries are not usually fully charged, they are connected in parallel with the main battery so they only get fully charged when decelerating in gear (slowing down or going downhill) with regenerative braking. But, like the main battery, they don't go flat - if they did the main battery would be flat too (since they connect in parallel) and the engine wouldn't start. But there has always been plenty of power to start the engine.
I'm not sure of the exact percentages, but its something like 80% charged when the engine is running, with regenerative braking providing the top up as and when it is working. I have a voltmeter connected to the secondary batteries, and the main batteries, so I can keep an eye on both. With 400ah of secondary battery capacity I don't need them fully charged every time I stop.

I can see this wouldnt do for a professional installation, because you need something you can fit and forget. If you did it like that the customer would bring it back saying the start stop was not working (which I don't need anyway). Although I don't know whether fitting a B2B charger would solve that problem.

Could I spend £600 on a B2B charger and still have the start stop inoperative (engine management) warnng light coming on?

Other than that it seems to be more environmentally friendly than a B2B charger set up. The B2B charger wouldn't make use of regenerative braking.

The B2B charger would also consume so much extra power it needs a fan to cool it down - Increasing the work of the alternator and possibly shortening its life?
I don't know what kind of cable lengths and gauge of cable you've used from the alternator to those 4 batteries but even with very heavy cable you cant realistically expect your alternator to "Fully charge" those 4 batteries just by going down a few hills now again and doing a bit of coasting
Ideally you don't want LA batteries sitting undercharged by ANY amount, not even 20%, they'll suphate very quickly and their capacity drops off , What I think you're saying is you think your batteries are being held at around 80% charge maximum (to enable power to go somewhere during regenerative breaking) but remeber if you've used some of their power for camping it'll take time for them to recharge back up to even the 80% charge level so the batteries will spend some time at an even lower charge level, maybe overnight, maybe several days, it depends on how much power you use and how much driving you do afterward and also if you use a mains charger (religiously) when you're parked up at home.
Ultimately you need to get the batteries COMPLETELY charged after use and that's going to take energy from either petrol or mains, if you don't then they'll soon fail so factor in the cost (both environmental and financial) of those short lived batteries into your equations maybe?
I personally use a Renogy B2B and that delivers it's stated current, I've measured Victron B2Bs and again they meet specs as you'd expect from Victron.
I'd expect the fitting of the B2B would prevent to stop start from working but only because the current being drawn by the B2B meant the engine needed to be running in order to replenish the starter battery, so basically everything would be working properly so to speak.
 
.........
The yellow light comes with info on the display panel saying start/stop inoperative - which potentially affects the emissions, so I guess thats an MOT fail
......
I am pretty sure that the MOT tester must turn on the ignition, and all the lights must come on. Then they must go out within 5 seconds, if they don't it's a fail.
The days of removing an oil pressure warning bulb are gone.
It seems that any light or warning message will be an MOT fail. I fitted all new brakes, including calipers to my car and took it for an MOT. The dashboard had an intermittent message saying 'Anti Skid service required'. I asked the MOT place if that would fail, he looked at all the possibilities on the computer and said no, provided it passes the rolling road brake tests. I drove it for an hour before the test with no message, but of course in the actual test the message came up. With all new brakes the rolling road test was fine but a different tester at the same place failed the car because it had a safety warning. He said although the brakes are fine, whether the safety warning is a faulty warning or an actual fault it fails. I stamped my foot and said what I want then is a car with no safety features and went and bought a 40 year old car with no electronics except a starter motor, lights and wipers. And ignition as it's petrol.

. . . . . . . . . Then I went and bought a one year old motorhome, :eek: which incidentally being French, has a BtoB charger built in.
 
If you are using Sterling Power B -B chargers you may need to reset it and an ignition connection is also recommended. If you give them a call they are usually very good at helping with issues.
 
Anyone had problems with smart alternator as fitted on recent (3 year old) Euro 6 motorhomes. My engine battery charge voltage fluctuates randomly between 12.4 and 14.2V, it has always seemed somewhat erratic but now much more so? It wouldn’t start for 10 minutes or so after a break this morning, even though when it did it was immediate with no sign of weakness from the battery in cranking.

Presently at a garage in Ayr where AA took me. They’ve measured voltage at the alternator terminals and their readings agree with mine, but they are somewhat flummoxed. Despite the low readings it usually rises back to 12.6V after a rest.

I can’t get a Fiat place to even look at it for over a week and we are due on the ferry to Ireland on Wednesday. Reluctant to just order a new alternator owing to high cost, and uncertainty that the problem may actually lie with other elements of the smart alternator control electrics. Looking online there seem to have been lots of problems with these, but no clear answers.

Just wondered if others on the forum had had the issue.
If you are using Sterling Power B -B chargers you may need to reset it and an ignition connection is also recommended. If you give them a call they are usually very good at helping with issues.
 
If you are using Sterling Power B -B chargers you may need to reset it and an ignition connection is also recommended. If you give them a call they are usually very good at helping with issues.
Voltage sensing is indeed a lost cause with smart alternators. I prefer D+ activation to ignition activation, ignition activation turns the B2B on before the engine is running putting a heavy load on the engine battery just when it needs power to start the engine. D+ only turns the B2B on when the engine is running.
 
I have to confess much of this is beyond my Ken. But after behaving itself for the last few months the gremlins are back. Once or twice part way through, or after a journey, after stopping the engine will not restart, usually for 10-15 minutes, after which it returns to normal. This usually (always?) happens the morning after the engine battery has been fully charged on EHU ( not often).

It happened again today. Only this time, in Italy, it wouldn’t start at all after 15 min, or after an hour. Called Nationwide (AA), breakdown man will come tomorrow 9am. (Sunday today).

Sods Law has it that it started again mysteriously after a hopeful attempt three hours later.

On stopping, voltage on control panel is low…12.3-12.4v but usually rapidly recovers to 12.7v after 10 min. According to the Phantom App however it can be as low as 11.9 V. Same today, but still wouldn’t start. Just a couple of clicks, one from the vicinity of the starter, one from near the fuse and relays box. Only 3 hrs later did Phantom app record 12.4V.

Haven’t had a chance to confirm voltages at battery with multimeter, but usually it agrees with the control panel with the app always under-reading by 2-3V.

Now it’s starting ok again I wonder if I’ll be wasting my money on a garage tomorrow as already two others have failed to find any answer. Will a full (expensive) diagnostic check find anything I wonder? There’s been no relevant warning lights or messages.

Some incompatibility of smart alternator with charging electrics perhaps?

I wonder if the low voltage reported by the Phantom app may suggest some circuit problem leading to mischief by the immobiliser.

Any thoughts welcome! Anyone had similar issue?
 
I have to confess much of this is beyond my Ken. But after behaving itself for the last few months the gremlins are back. Once or twice part way through, or after a journey, after stopping the engine will not restart, usually for 10-15 minutes, after which it returns to normal. This usually (always?) happens the morning after the engine battery has been fully charged on EHU ( not often).

It happened again today. Only this time, in Italy, it wouldn’t start at all after 15 min, or after an hour. Called Nationwide (AA), breakdown man will come tomorrow 9am. (Sunday today).

Sods Law has it that it started again mysteriously after a hopeful attempt three hours later.

On stopping, voltage on control panel is low…12.3-12.4v but usually rapidly recovers to 12.7v after 10 min. According to the Phantom App however it can be as low as 11.9 V. Same today, but still wouldn’t start. Just a couple of clicks, one from the vicinity of the starter, one from near the fuse and relays box. Only 3 hrs later did Phantom app record 12.4V.

Haven’t had a chance to confirm voltages at battery with multimeter, but usually it agrees with the control panel with the app always under-reading by 2-3V.

Now it’s starting ok again I wonder if I’ll be wasting my money on a garage tomorrow as already two others have failed to find any answer. Will a full (expensive) diagnostic check find anything I wonder? There’s been no relevant warning lights or messages.

Some incompatibility of smart alternator with charging electrics perhaps?

I wonder if the low voltage reported by the Phantom app may suggest some circuit problem leading to mischief by the immobiliser.

Any thoughts welcome! Anyone had similar issue?
I should note whilst refusing to start the brake pedal will not depress. (2019-2020 140 auto Fiat A Class model)
 
I don't know what kind of cable lengths and gauge of cable you've used from the alternator to those 4 batteries but even with very heavy cable you cant realistically expect your alternator to "Fully charge" those 4 batteries just by going down a few hills now again and doing a bit of coasting
Ideally you don't want LA batteries sitting undercharged by ANY amount, not even 20%, they'll suphate very quickly and their capacity drops off , What I think you're saying is you think your batteries are being held at around 80% charge maximum (to enable power to go somewhere during regenerative breaking) but remeber if you've used some of their power for camping it'll take time for them to recharge back up to even the 80% charge level so the batteries will spend some time at an even lower charge level, maybe overnight, maybe several days, it depends on how much power you use and how much driving you do afterward and also if you use a mains charger (religiously) when you're parked up at home.
Ultimately you need to get the batteries COMPLETELY charged after use and that's going to take energy from either petrol or mains, if you don't then they'll soon fail so factor in the cost (both environmental and financial) of those short lived batteries into your equations maybe?
I personally use a Renogy B2B and that delivers it's stated current, I've measured Victron B2Bs and again they meet specs as you'd expect from Victron.
I'd expect the fitting of the B2B would prevent to stop start from working but only because the current being drawn by the B2B meant the engine needed to be running in order to replenish the starter battery, so basically everything would be working properly so to speak.
Can I also emphasise that a conventional lead-acid battery at 80% full charge is at 60% useable charge.
 
I have to confess much of this is beyond my Ken. But after behaving itself for the last few months the gremlins are back. Once or twice part way through, or after a journey, after stopping the engine will not restart, usually for 10-15 minutes, after which it returns to normal. This usually (always?) happens the morning after the engine battery has been fully charged on EHU ( not often).

It happened again today. Only this time, in Italy, it wouldn’t start at all after 15 min, or after an hour. Called Nationwide (AA), breakdown man will come tomorrow 9am. (Sunday today).

Sods Law has it that it started again mysteriously after a hopeful attempt three hours later.

On stopping, voltage on control panel is low…12.3-12.4v but usually rapidly recovers to 12.7v after 10 min. According to the Phantom App however it can be as low as 11.9 V. Same today, but still wouldn’t start. Just a couple of clicks, one from the vicinity of the starter, one from near the fuse and relays box. Only 3 hrs later did Phantom app record 12.4V.

Haven’t had a chance to confirm voltages at battery with multimeter, but usually it agrees with the control panel with the app always under-reading by 2-3V.

Now it’s starting ok again I wonder if I’ll be wasting my money on a garage tomorrow as already two others have failed to find any answer. Will a full (expensive) diagnostic check find anything I wonder? There’s been no relevant warning lights or messages.

Some incompatibility of smart alternator with charging electrics perhaps?

I wonder if the low voltage reported by the Phantom app may suggest some circuit problem leading to mischief by the immobiliser.

Any thoughts welcome! Anyone had similar issue?
this sort of problem can be difficult to diagnose so the more you can do yourself the better.
So I’d look to isolate the habitation electrics from the vehicle electrics by removing relevant fuses. During this test your LB will not be charged during driving and the vehicle battery (SB) will not be charged from EHU or solar.
You need to identify and remove fuse(s) located near the SB that go off to habitation electrics/LB. Also remove fuses from EHU feed to SB and solar if you have it and it has an output to the SB.
Live with this for a bit and see if the problem persists. If it does you can comfortably say the problem is not conversion related but a Fiat problem.

Also check with your supplier if there is an aftermarket immobiliser fitted which may have gone rogue.

Certainly the advice above about B2B charger is a must with a Euro 6 engine because of the smart alternator. I know from my own experience it isn’t always easy to determine what the campervan/MH manufacturer has built in - my first step was to ask the factory and supplier and I eventually got the (disappointing) truth.
 
For now it seems a remote reset of the immobiliser by Phantom (aka Moving Intelligence) has resolved the problem. But no explanation of the low voltages on stopping…other than the shenanigans of the smart alternator, or why the alarm systems reading of the voltage is so much lower than the control panel’s.
 
For now it seems a remote reset of the immobiliser by Phantom (aka Moving Intelligence) has resolved the problem. But no explanation of the low voltages on stopping…other than the shenanigans of the smart alternator, or why the alarm systems reading of the voltage is so much lower than the control panel’s.
The low voltage would be explained by the working of a split charge relay (if you do not have an B2B) alongside a smart alternator. The split charge relay joins the leisure battery to the engine battery when the engine is running. The smart alternator system keeps the engine battery at a low voltage so that there is room in it to recover energy when the you are slowing down or braking. However because you have joined the two batteries together the system sees them as one and reduces the voltage level of both. A B2B would solve this problem, the motorhome should have been fitted with one from new but some manufacturers seem to have been slow to understand what is needed.
 
The low voltage would be explained by the working of a split charge relay (if you do not have an B2B) alongside a smart alternator. The split charge relay joins the leisure battery to the engine battery when the engine is running. The smart alternator system keeps the engine battery at a low voltage so that there is room in it to recover energy when the you are slowing down or braking. However because you have joined the two batteries together the system sees them as one and reduces the voltage level of both. A B2B would solve this problem, the motorhome should have been fitted with one from new but some manufacturers seem to have been slow to understand what is needed.
Yes but. The leisure battery charge is fine. Only the engine battery shows low level eg. 12.3v after stopping but rising to 12.6-12.7 within 10-15 minutes
 
Yes but. The leisure battery charge is fine. Only the engine battery shows low level eg. 12.3v after stopping but rising to 12.6-12.7 within 10-15 minutes
Oops. Thought it was your leisure battery, I had forgotten your earlier posts. The 12.3V is consistent with a smart alternator, that is the sort of voltage it would be aiming for. The rising voltage suggests the battery is getting charged from another source. Once the alternator and ECU have shut down there is nothing to stop the engine battery reaching a higher voltage if something else is feeding it.
 
Oops. Thought it was your leisure battery, I had forgotten your earlier posts. The 12.3V is consistent with a smart alternator, that is the sort of voltage it would be aiming for. The rising voltage suggests the battery is getting charged from another source. Once the alternator and ECU have shut down there is nothing to stop the engine battery reaching a higher voltage if something else is feeding it.
Could this be due to the Recovery Effect if there is a load on the battery which ends when the engine is switched off? (Sorry if this is a numty question).
 
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