T6.1 disable smart alternator?

[rileyrussell.89]

Has anyone successfully disabled the smart alternator to allow a simple battery isolator to charge a second battery?

 

[Loz]

The 6.1 california has a menu option to select max charge that does this. Presumably if you have the factory second battery you might also have this option.

 

[Pete C]

Has anyone successfully disabled the smart alternator to allow a simple battery isolator to charge a second battery?

It‘s been discussed a few times, but no-one has done it to my knowledge. Some folks have said “try this, it works on some other random make/model”, but you run the risk of damaging the charging circuits, or triggering faults.

The bottom line is that a decent DC-DC charger will always do a better job than a simple switch, and it’s only a few hundred £\$ which is nothing compared to what these vans cost.

Pete

 

[Dellmassive]

Why would you want to do that?.... as above just swap the Relay for a Dc-dc charger..... job done.

FYI- if you remove the LIN Bus data conection from the battery NEG post the ECM will loose battery data and use substitute values. This will effectively disable the energy management system. (Will raise alternator output to raise system voltage) This is untested on the T6.1 and not advised anyway.

 

[rileyrussell.89]

Why would you want to do that?.... as above just swap the Relay for a Dc-dc charger..... job done.

FYI- if you remove the LIN Bus data conection from the battery NEG post the ECM will loose battery data and use substitute values. This will effectively disable the energy management system. (Will raise alternator output to raise system voltage) This is untested on the T6.1 and not advised anyway.

From the huge amount of research I’ve done and my experience with my current T5.1s 2nd battery hooked up via an isolator, I believe the dcdc charger doesn’t charge sufficiently if only doing short (20 min) trips once a day.

 

[The Bear78]

Good evening.
If you modify the charging system to enable second battery charging all the time how will the main battery charge be affected during short journeys? Just a thought.

 

[Loz]

Good evening.
If you modify the charging system to enable second battery charging all the time how will the main battery charge be affected during short journeys? Just a thought.

its not affected

 

[rileyrussell.89]

I’ll use my new van as a test dummie and disconnect the negative sensor on batt, if it doesn’t throw codes straight away one would think it’s ok.

 

[Loz]

I’ll use my new van as a test dummie and disconnect the negative sensor on batt, if it doesn’t throw codes straight away one would think it’s ok.

See if you have the proper 6.1 option to max charge first.

 

[rileyrussell.89]

See if you have the proper 6.1 option to max charge first.

How would one do that?