Generator / alternator failure error

Perfectos said:

1) Is the "coasting" function turned on ?

2) Can you turn it off ?

3) does it affect alternator behaviour?

From what you say above, with engine running no power getting to starter battery ?
What about the Leisure batteries whilst engine is running?

How many pins is the tow bar electric socket?
Are you using a converter plug to change from 7 / 13 etc. ?

What happens with the alternator when the bike rack is unplugged totally ?

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Coasting function is on, always is. Can't switch it off, only have basic Carista.

Leisure batteries depleate when the van is running, presume that's to try a maintain voltage for the engine.

When bike rack is unplugged it makes do difference at all.

Today I started the van courtesy of the engine battery being charged on hook up. Bike rack unplugged, put the blower on full with the AC, that should have initiated the alternator to charge, it didn't.

VW Trier fitted another new alternator to my van to remedy the charging issue, two alternators in a vehicle under two years old and 14K miles is not normal.
When I dropped the vehicle off I pointed out the oil mist around what I been advised I'd the HP diesel pump, they cleaned up this area and said they had tightened the compression fitting on the pipe.
I have no confidence they found the root cause of the failures.

To add to my disastrous trip so far the VW workshop damaged my beloved van, new passenger door and mirror to be fitted, paint damaged to front wing and surface marks on rear body panel they say will polish out, we will see.

So another week to add to the three I've already been waiting, I am fuming as you would expect.

I've involved VW customer care Europe and I'm seeking assurance that my OEM paint warranty remains unaffected.

vbk1975 said:

If it is getting into the alternator brushes / slip ring. Not sure what tools and access you have but maybe heavy dose of brake cleaner.

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Be careful if spraying brake cleaner into and around the alternator.

Many brake cleaners are highly flammable so if you do try it, give it plenty of time to fully evaporate before switching on the ignition and attempting to start the engine. Any internal sparking from the alternator brushes could end up causing a fire.

Don't ask me how I know!!!

EDIT :

Sorry, just read your later post.

That's shocking. I would be fuming mad as well. What on earth were they playing at?

Today I got my van back.

It's now charging with the new alternator but I still have an error message ODB 501200 which VW have not resolved.

I can clear it with my Carista but it just comes back.

I know it's charging as I can watch the battery voltage on live data with the Carista, it's 14.1 V when I've got the van on max charge.

I had 19 ecu errors when I ran a scan myself, all but the one above have cleared.

One horror error was an ad blue 650 miles engine no start warning, that fortunately seems to have cleared itself.

I have three weeks holiday left out of my original seven. Plan to head south to Austria tomorrow with my fingers crossed that the rest of the trip will be trouble free.

Vehicles are just too complicated for their own good these days.

And finally, the body work repair looks good, warranty issues still to be resolved. VW will likely do their usual so my expectations are not high.

sbmcd said:

Today I got my van back.

It's now charging with the new alternator but I still have an error message ODB 501200 which VW have not resolved.

I can clear it with my Carista but it just comes back.

I know it's charging as I can watch the battery voltage on live data with the Carista, it's 14.1 V when I've got the van on max charge.

I had 19 ecu errors when I ran a scan myself, all but the one above have cleared.

One horror error was an ad blue 650 miles engine no start warning, that fortunately seems to have cleared itself.

I have three weeks holiday left out of my original seven. Plan to head south to Austria tomorrow with my fingers crossed that the rest of the trip will be trouble free.

Vehicles are just too complicated for their own good these days.

And finally, the body work repair looks good, warranty issues still to be resolved. VW will likely do their usual so my expectations are not high.

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Does the voltage look like it is varying, ie does it look like it functioning correctly but just the comms message or does it appear to be locked onto one voltage set point?

The fault would suggest that the Gateway Module (BCM) can’t see the Alternator communicating and flags this error code. But if the alternator is varying the voltage as expected, esp if if changes with you selecting max on and off then the alternator is seeing the communications.

If the alternator appears to be varying the voltage and not just a set point then it is a weird fault, they might have fitted an older part or there is a strange configuration mismatch in the BCM.

vbk1975 said:

Does the voltage look like it is varying, ie does it look like it functioning correctly but just the comms message or does it appear to be locked onto one voltage set point?

The fault would suggest that the Gateway Module (BCM) can’t see the Alternator communicating and flags this error code. But if the alternator is varying the voltage as expected, esp if if changes with you selecting max on and off then the alternator is seeing the communications.

If the alternator appears to be varying the voltage and not just a set point then it is a weird fault, they might have fitted an older part or there is a strange configuration mismatch in the BCM.

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Thanks for those suggestions, I'll monitor it off and on max charge to see if the voltage varies during our journey tomorrow.

I appears as if it's not smart charging see pics from Carista, van ran for 5 1/2 hrs at 14.2 - 14.3 V.

The intermittent emissions error as returned. Possibly overvoltage on an emissions sensor?

sbmcd said:

I appears as if it's not smart charging see pics from Carista, van ran for 5 1/2 hrs at 14.2 - 14.3 V.

The intermittent emissions error as returned. Possibly overvoltage on an emissions sensor?

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From this it appears that the voltage is probably default charging set point, which would confirm that the there isn’t comms to alternator either way. It appears rhe BMS is working correctly as you have current and SOC. Do you have any form of 12v message or stop-start unavailable warning?

The only linkage I can think of with the Alternator and Ad-blu sensor is some form of local harness damage or water ingress that effects both. The sensors should happily cope with 9-16v operating ranges without error but you never know.

vbk1975 said:

From this it appears that the voltage is probably default charging set point, which would confirm that the there isn’t comms to alternator either way. It appears rhe BMS is working correctly as you have current and SOC. Do you have any form of 12v message or stop-start unavailable warning?

The only linkage I can think of with the Alternator and Ad-blu sensor is some form of local harness damage or water ingress that effects both. The sensors should happily cope with 9-16v operating ranges without error but you never know.

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The stop start has not been working but not sure it does if you have a trailer board plugged in. Certainly no stop / start warning on the display.

Thanks for the info on operating ranges, that's useful.

We will try another VW workshop in Austria today. We are now considering just coming back to the UK, this trip has been a bit of a nightmare and I don't want to be in a position where we have to fly home and get the van shipped back.

sbmcd said:

The stop start has not been working but not sure it does if you have a trailer board plugged in. Certainly no stop / start warning on the display.

Thanks for the info on operating ranges, that's useful.

We will try another VW workshop in Austria today. We are now considering just coming back to the UK, this trip has been a bit of a nightmare and I don't want to be in a position where we have to fly home and get the van shipped back.

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I believe Stop/Start is disabled if you have towbar electrics connected and the Smart Alternator defaults to Max Charge as well.
The Adblue message you have is not connected and coincidental I'm afraid.

WelshGas said:

I believe Stop/Start is disabled if you have towbar electrics connected and the Smart Alternator defaults to Max Charge as well.
The Adblue message you have is not connected and coincidental I'm afraid.

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Thanks

WelshGas said:

I believe Stop/Start is disabled if you have towbar electrics connected and the Smart Alternator defaults to Max Charge as well.
The Adblue message you have is not connected and coincidental I'm afraid.

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I'm at VW now they will run a diagnostic on the ad blue system.

Diagnostic on ad blue system showed there had been an intermittent fault, they could look at it for me but we would have to book into another hotel and leave the van with them.

We decided we'd had enough of VW workshops and hotels this trip so we stayed at the great lakeside campsite we found for a week then head home a week early.

The oil / fuel mist has returned around the pump so pretty sure the contamination from that is the root cause of the generator issue.

Some error codes have returned but the van is running ok, final journey to Amsterdam today, ferry tomorrow.

The Ad Blue no start in 650 miles message has not returned so far thankfully.

I'll book it in to VW when we get back.

sbmcd said:

Diagnostic on ad blue system showed there had been an intermittent fault, they could look at it for me but we would have to book into another hotel and leave the van with them.

We decided we'd had enough of VW workshops and hotels this trip so we stayed at the great lakeside campsite we found for a week then head home a week early.

The oil / fuel mist has returned around the pump so pretty sure the contamination from that is the root cause of the generator issue.

Some error codes have returned but the van is running ok, final journey to Amsterdam today, ferry tomorrow.

The Ad Blue no start in 650 miles message has not returned so far thankfully.

I'll book it in to VW when we get back.

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What a shocker of a trip, I truly feel for you.

Perfectos said:

What a shocker of a trip, I truly feel for you.

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Thanks, certainly one to forget.

Made it home today without further issues.

On my journey home today I recorded the following fault codes using my Carista ODB, thought those who have been following this may be interested. The Ad Blue and Generator Comms faults are clear to see:

Basic OBD2:
P2EAE (Pending) - Manufacturer-specific code
(tap to search)

P2EAF (Pending) - Manufacturer-specific code
(tap to search)

CAN network gateway:
U105200 - Generator: No communication
Freeze frame
Priority: 2
Malfunction frequency counter: 18
Unlearning counter: 237
Odometer reading: 15253.4 miles
Date: 28 Sept 2026 12:16:45 pm
Terminal 30 power supply: 12.4 V
Terminal 15: on

U140600 - Static current: too large
Freeze frame
Priority: 7
Malfunction frequency counter: 1
Unlearning counter: 21
Odometer reading: 15382 miles
Date: 29 Sept 2026 07:51:37 pm
Terminal 30 power supply: 12.6 V
Terminal 15: off

Engine:
U100800 - Data Bus on Board Diagnostic Interface: Check event memory
Freeze frame
Priority: 2
Malfunction frequency counter: 7
Unlearning counter: 40
Odometer reading: 15253.4 miles
Date: 28 Sept 2026 12:52:34 pm
Engine rpm: 1041 RPM
Normed load value: 10.6 %
Vehicle speed: 0 mph
Coolant temperature: 67 °C
Intake air temperature: 30 °C
Ambient air pressure: 14.65 PSI
Voltage terminal 30: 12.14 V

U100800 - Data Bus on Board Diagnostic Interface: Check event memory
Freeze frame
Priority: 2
Malfunction frequency counter: 11
Unlearning counter: 40
Odometer reading: 15253.4 miles
Date: 28 Sept 2026 12:51:39 pm
Engine rpm: 883.5 RPM
Normed load value: 18.4 %
Vehicle speed: 0 mph
Coolant temperature: 65 °C
Intake air temperature: 37 °C
Ambient air pressure: 14.65 PSI
Voltage terminal 30: 12.1 V

P2EAF00 - Reductant Injection Valve Stuck Closed Bank 1 Unit 2
Freeze frame
Priority: 2
Malfunction frequency counter: 1
Unlearning counter: 40
Odometer reading: 15384.5 miles
Engine rpm: 1642 RPM
Normed load value: 91.8 %
Vehicle speed: 37.9 mph
Coolant temperature: 87 °C
Intake air temperature: 20 °C
Ambient air pressure: 14.5 PSI
Voltage terminal 30: 14.12 V

P2EAE00 - Reductant Injection Valve Circuit Range/Performance Bank 1: Unit 2
Freeze frame
Priority: 2
Malfunction frequency counter: 1
Unlearning counter: 40
Odometer reading: 15333.6 miles
Date: 29 Sept 2026 10:53:17 am
Engine rpm: 906.5 RPM
Normed load value: 22.4 %
Vehicle speed: 0 mph
Coolant temperature: 18 °C
Intake air temperature: 19 °C
Ambient air pressure: 14.65 PSI
Voltage terminal 30: 12 V

Instrument cluster:
U111000 - Function restriction due to communication interruption
Freeze frame
Priority: 6
Malfunction frequency counter: 1
Unlearning counter: 19
Odometer reading: 15277.6 miles
Date: 28 Sept 2026 01:58:31 pm

U111000 - Function restriction due to communication interruption
Freeze frame
Priority: 6
Malfunction frequency counter: 1
Unlearning counter: 19
Odometer reading: 15277.6 miles
Date: 28 Sept 2026 01:58:31 pm

Telematics:
B1915F1 - Online services: Function temporarily restricted due to battery budget
Freeze frame
Priority: 6
Malfunction frequency counter: 1
Unlearning counter: 37
Odometer reading: 15333.6 miles
Date: 28 Sept 2026 04:40:19 pm

Obtained with Carista 10.0 for Android.
Download app: https://play.google.com/store/apps/details?id=com.prizmos.carista
Facebook: https://www.facebook.com/caristaapp

sbmcd said:

Made it home today without further issues.

On my journey home today I recorded the following fault codes using my Carista ODB, thought those who have been following this may be interested. The Ad Blue and Generator Comms faults are clear to see:

Basic OBD2:
P2EAE (Pending) - Manufacturer-specific code
(tap to search)

P2EAF (Pending) - Manufacturer-specific code
(tap to search)

CAN network gateway:
U105200 - Generator: No communication
Freeze frame
Priority: 2
Malfunction frequency counter: 18
Unlearning counter: 237
Odometer reading: 15253.4 miles
Date: 28 Sept 2026 12:16:45 pm
Terminal 30 power supply: 12.4 V
Terminal 15: on

U140600 - Static current: too large
Freeze frame
Priority: 7
Malfunction frequency counter: 1
Unlearning counter: 21
Odometer reading: 15382 miles
Date: 29 Sept 2026 07:51:37 pm
Terminal 30 power supply: 12.6 V
Terminal 15: off

Engine:
U100800 - Data Bus on Board Diagnostic Interface: Check event memory
Freeze frame
Priority: 2
Malfunction frequency counter: 7
Unlearning counter: 40
Odometer reading: 15253.4 miles
Date: 28 Sept 2026 12:52:34 pm
Engine rpm: 1041 RPM
Normed load value: 10.6 %
Vehicle speed: 0 mph
Coolant temperature: 67 °C
Intake air temperature: 30 °C
Ambient air pressure: 14.65 PSI
Voltage terminal 30: 12.14 V

U100800 - Data Bus on Board Diagnostic Interface: Check event memory
Freeze frame
Priority: 2
Malfunction frequency counter: 11
Unlearning counter: 40
Odometer reading: 15253.4 miles
Date: 28 Sept 2026 12:51:39 pm
Engine rpm: 883.5 RPM
Normed load value: 18.4 %
Vehicle speed: 0 mph
Coolant temperature: 65 °C
Intake air temperature: 37 °C
Ambient air pressure: 14.65 PSI
Voltage terminal 30: 12.1 V

P2EAF00 - Reductant Injection Valve Stuck Closed Bank 1 Unit 2
Freeze frame
Priority: 2
Malfunction frequency counter: 1
Unlearning counter: 40
Odometer reading: 15384.5 miles
Engine rpm: 1642 RPM
Normed load value: 91.8 %
Vehicle speed: 37.9 mph
Coolant temperature: 87 °C
Intake air temperature: 20 °C
Ambient air pressure: 14.5 PSI
Voltage terminal 30: 14.12 V

P2EAE00 - Reductant Injection Valve Circuit Range/Performance Bank 1: Unit 2
Freeze frame
Priority: 2
Malfunction frequency counter: 1
Unlearning counter: 40
Odometer reading: 15333.6 miles
Date: 29 Sept 2026 10:53:17 am
Engine rpm: 906.5 RPM
Normed load value: 22.4 %
Vehicle speed: 0 mph
Coolant temperature: 18 °C
Intake air temperature: 19 °C
Ambient air pressure: 14.65 PSI
Voltage terminal 30: 12 V

Instrument cluster:
U111000 - Function restriction due to communication interruption
Freeze frame
Priority: 6
Malfunction frequency counter: 1
Unlearning counter: 19
Odometer reading: 15277.6 miles
Date: 28 Sept 2026 01:58:31 pm

U111000 - Function restriction due to communication interruption
Freeze frame
Priority: 6
Malfunction frequency counter: 1
Unlearning counter: 19
Odometer reading: 15277.6 miles
Date: 28 Sept 2026 01:58:31 pm

Telematics:
B1915F1 - Online services: Function temporarily restricted due to battery budget
Freeze frame
Priority: 6
Malfunction frequency counter: 1
Unlearning counter: 37
Odometer reading: 15333.6 miles
Date: 28 Sept 2026 04:40:19 pm

Obtained with Carista 10.0 for Android.
Download app: https://play.google.com/store/apps/details?id=com.prizmos.carista
Facebook: https://www.facebook.com/caristaapp

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Welcome back - let us know what the prognosis is

Perfectos said:

Welcome back - let us know what the prognosis is

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I will.