Latest Caravans and Euro 6 Car Engines

kingfisher999
kingfisher999 Forum Participant Posts: 4
edited May 2021 in Caravan & Motorhome Chat #1

I recently stumbled across a post (dated 2017) that described problems caravaners were encountering following the introduction of the (then) newly introduced Euro 6 engines. Because of the regeneration system of the engines (to improve fuel efficiency), the car battery is kept partially discharged so the battery can take extra charge during breaking. This results in the battery voltage being "low" during cruising and therefore discharging the caravan battery to the same state as the car battery. I understand this has resulted in drivers arriving at their destination (particularly after long motorway runs) with a "flat" caravan battery that will not drive the motor mover and a defrosted fridge (which doesn't like whats going on). Additionally, there have been reports the ATC does not like this situation either and shows error codes.

 

Can anyone shed any light on this? Have the manufacturers of more recent caravans introduced design changes to their electrics to over come these problems (particularly Buccaneer)?

 

Comments

  • JVB66
    JVB66 Forum Participant Posts: 22,892
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    edited May 2021 #2

    Do not know about battery discharging ,but there was/is a problem with smart alternators fitted to some cars, that would "shut down" when vehicle battery was charged, so not supplying power to c/van fridge ,this is normally rectified ,with some sort of Gizmo that up to speed tow bar fitters install to "fool? the alternator into giving power

  • SeasideBill
    SeasideBill Forum Participant Posts: 2,112
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    edited May 2021 #3

    You’re correct, regenerative braking is only effective if the starter battery has some spare storage capacity to absorb the charge created by the alternator during deceleration.  The issue, and solution to charging auxiliary batteries is well explained HERE

  • kingfisher999
    kingfisher999 Forum Participant Posts: 4
    edited May 2021 #4

     I have read the article and it ties in with what I have read before (hence the post). My concern is - if there is an "incompatibility" between the car and the caravan which has been introduced by all car manufactures to comply with regulations, then I would have thought it would have been incumbent on caravan manufacturers to introduce a solution (eg battery to battery charger) or other solution to this problem so caravaners don't have to go and knife and fork a fix with variable success when they know what is needed.

  • KeefySher
    KeefySher Forum Participant Posts: 1,128
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    edited May 2021 #5

    Been towing caravan with Euro 6 engined cars since 2015 without issue.

    The first Euro 6 was a 2012 model year car.

     

    There are car manufacturers and tow bar fitters that don't fit the requisite wiring to power the caravan fridge, unless you specify it, even factory built,  BMW in particular.

  • SeasideBill
    SeasideBill Forum Participant Posts: 2,112
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    edited May 2021 #6

    Euro 6 is a bit of a red herring. The question is whether the vehicle is fitted with a smart alternator. In the case of vehicles fitted with start/stop systems, then almost certainly yes, otherwise you’ll need to check, particularly for earlier models.

  • EmilysDad
    EmilysDad Forum Participant Posts: 8,973
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    edited May 2021 #7

    never been a problem with my Euro 6, stop/start Merc with factory towbar 

  • Unknown
    Unknown Forum Participant
    edited May 2021 #8
    The user and all related content has been Deleted User
  • SeasideBill
    SeasideBill Forum Participant Posts: 2,112
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    edited May 2021 #9

    From what I remember of discussions at the time, it was more of a theoretical problem than something real. I’m sure the technology has moved on since then anyway.

  • Snowy1
    Snowy1 Forum Participant Posts: 263
    edited July 24 #10

    Added to this there appears to be no mention of the sudden boost in supply voltage to the caravans’ fridge & battery during the towcars regenerative braking charging cycle? There is a unit made by Sterling that deals with both issues, hence under charging as stated in the above post and overcharging due to voltages in well in excessive of the average 14 volt supply to the auxiliaries. This unit is the Stirling BBC1225 or BBC1240 for higher outputs, it keeps the supply voltage to both fridge & caravan battery to a constant 14.2 volts no matter what the varying input voltage is from the towcar.

  • flatcoat
    flatcoat Forum Participant Posts: 1,571
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    edited July 24 #11

    I tow with a PHEV that in sport setting has considerable regen braking. Never had a problem and have towed a few thousand miles. 

  • richardandros
    richardandros Club Member Posts: 2,680 ✭✭✭
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    edited July 24 #12

    I've been towing with a VW Touareg Euro 6 stop/start engine since 2015 and also never had any problems.  I always disable the stop/start when towing anyway.

  • Snowy1
    Snowy1 Forum Participant Posts: 263
    edited July 24 #13

    I believe those that say they haven’t had any problems as there are so many who say they haven’t, it’s just the laws of physics that applies to these Euro 6 systems and the way they work just doesn’t add up? Interesting subject to say the least. These systems are so complex in the way they work that even the outside air temperature sensor is programmed into the system, the reason being that in sub zero temperatures, the system will not allow the towcars battery to discharge down to the 80% minimum level, reason being the vehicle failing to start in the cold the following morning. In other words, the colder the climate the less the car’s battery is allowed to discharge leaving room for a regenerative charge, in continuous sub zero the regenerative may even be totally disabled?