Generator / alternator failure error

sbmcd

sbmcd

Top Poster
VIP Member
Messages
1,312
Location
Edinburgh
Vehicle
T6.1 Ocean 150
Hi,

My Nov 24 California Ocean 150 has come up with a generator error, it's booked in for a warranty repair but anyone else had this.

See attached Carista screenshots

Screenshot_20250505-143626.png

Screenshot_20250505-143715.png
 
Any symptoms?
Fortunately happened on the very last part of a Journey home from Wales, dash warning came up with red battery display and a warning to stop, I could watch the battery voltage dropping as we continued the last part of the journey, it got us home on the remaining power.

I did try to clear the fault but it returned immediately.

Van was running fine but battery was not charging.
 
Looks like it may need a new alternator. Sometimes the diodes just fail.
 
I have not checked anything under the bonnet.
Can be checked from the Drivers side (U.K.) wheel arch , rotate the road wheels left to give a better view / access , you should be able to see the Serpentine belt and tensioner.
 
Thanks but I'm a bit broken at the moment, classic bike racing at Anglesey ended with quite a bad crash and I'm not very mobile.

No weight bearing on one leg for 6 weeks.

I'll leave it to VW on Tuesday.
 
Van in at VW today, on a collect and return, they have ordered a new alternator which will be delivered and fitted on Thursday, they did not go into any detail on what exactly went wrong with it.
 
It's now aug 26 we are in Europe and the same thing has happened again, red battery warning. I've taken the van to two VW dealerships but problem not resolved.
Currently stuck in Trier in a campsite where we were taken by the recovery vehicle.

It's looking like 9 Sept before they can fix it.

PXL_20260821_174236101.jpg

PXL_20260821_183615826.jpg

Screenshot_20260822-080427.png
 
It's now aug 26 we are in Europe and the same thing has happened again, red battery warning. I've taken the van to two VW dealerships but problem not resolved.
Currently stuck in Trier in a campsite where we were taken by the recovery vehicle.

It's looking like 9 Sept before they can fix it.

View attachment 151098

View attachment 151099

View attachment 151100
So battery has gone flat, not just warning. Ie power failure. I assume the recovery agent checked belt etc? No other symptoms?

If the battery has gone flat then

1. Alternator again
2. Positive Wiring issue between alternator and main battery fuse box or aux wire to alternator. If the LIN bus wire fails then whilst it puts on warning light I would expect a default target charge voltage not power off.
3. Earth issue, but given alternator earths through engine, an engine Earth issue would normally show up with other issues.

If you feel so inclined, I would definitely have a look at the wiring, alternator end and the battery fuse box, I would give the cable a wiggle and see if it moves, also any sign of heat or arcing that might indicate a a loose terminal. The nuts on these things can be crossed threaded, so tight but not clamped.

Repeated alt failure could point to other stuff and perhaps load dumps but I would check the basics first.
 
Van had 11.7 v when we had to stop, used my battery jump pack to get the van into our camping place. Van had also drained the leisure batteries to try and maintain a voltage.
Now on hook up leisure batteries now changed and engine battery back to 13 V.

Van drivable but only for short journeys. As there is now charge getting from the alternator.
 
So battery has gone flat, not just warning. Ie power failure. I assume the recovery agent checked belt etc? No other symptoms?

If the battery has gone flat then

1. Alternator again
2. Positive Wiring issue between alternator and main battery fuse box or aux wire to alternator. If the LIN bus wire fails then whilst it puts on warning light I would expect a default target charge voltage not power off.
3. Earth issue, but given alternator earths through engine, an engine Earth issue would normally show up with other issues.

If you feel so inclined, I would definitely have a look at the wiring, alternator end and the battery fuse box, I would give the cable a wiggle and see if it moves, also any sign of heat or arcing that might indicate a a loose terminal. The nuts on these things can be crossed threaded, so tight but not clamped.

Repeated alt failure could point to other stuff and perhaps load dumps but I would check the basics first.
Thanks that's very useful.
 
I did fit a solar panel to the van this year but it does not change the engine battery, only the leisure batteries.
Don't think that's related.
 
Thanks that's very useful.
The other thing could be a secondary immobiliser that has been added into the ignition circuits, if it is badly wired or has a internal issue then it might be switching on and off ignition feed that creates load dumps but it is not obvious as the issue is restricted to a few circuits that have been cut into.
 
The other thing could be a secondary immobiliser that has been added into the ignition circuits, if it is badly wired or has a internal issue then it might be switching on and off ignition feed that creates load dumps but it is not obvious as the issue is restricted to a few circuits that have been cut into.
No secondary imobiliser.

The recovery company checked all the main connections including the battery ones on top of the battery.

The only common factor each time it has failed is I've had either a trailer, or bike rack plugged in to the factory fitted two bar. I use the van a lot with the bike rack in particular for long journeys and that's never been an issue. It does not start charging when the tow bar is unplugged.

First time was with my trailer, second time with my bike rack
 
I have a volt meter with me and can see the battery is not being charged.
 
Had a nosey at the alternator from above, don't know what this does but there is evidence of oil mist around it and it's directly above the alternator.

PXL_20260823_081001230.jpg
 
No secondary imobiliser.

The recovery company checked all the main connections including the battery ones on top of the battery.

The only common factor each time it has failed is I've had either a trailer, or bike rack plugged in to the factory fitted two bar. I use the van a lot with the bike rack in particular for long journeys and that's never been an issue. It does not start charging when the tow bar is unplugged.

First time was with my trailer, second time with my bike rack
Did they check under here ?

The only linkage to trailer towing is some companies change the target voltage if a trailer is connected due to the way the voltage switches work in caravans, also other companies also disable stop-start.

1787477749818.png
 
Did they check under here ?

The only linkage to trailer towing is some companies change the target voltage if a trailer is connected due to the way the voltage switches work in caravans, also other companies also disable stop-start.

View attachment 151143
I know the Cali senses if a trailer or something is plugged in. Don't know how or if this affects target voltage.
 
Did they check under here ?

The only linkage to trailer towing is some companies change the target voltage if a trailer is connected due to the way the voltage switches work in caravans, also other companies also disable stop-start.

View attachment 151143
The recovery technician noticed the oil mist, advised that may be possible issue.
 
I know the Cali senses if a trailer or something is plugged in. Don't know how or if this affects target voltage.
My experience on other cars is that Smart Charging stops and you get a steady state ~14v.
 
The recovery technician noticed the oil mist, advised that may be possible issue.
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.
 
Did they check under here ?

The only linkage to trailer towing is some companies change the target voltage if a trailer is connected due to the way the voltage switches work in caravans, also other companies also disable stop-start.

View attachment 151143
Yes they checked all the connections in there.
 
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 ?
 
Back
Top