Model Y tow bar electrics not working

[GeorgeSymonds]

I’ve an early MY in the UK with Ryzen/Li Ion low volt battery.

It really doesn’t help I’m afraid but ‘Tesla working on…’ is a common feature of the brand

 

[MrBadger]

I’ve an early MY in the UK with Ryzen/Li Ion low volt battery.

Tesla Remote Techician mentioned that it would work with an old Lead acid battery. Can anyone confirm that? Reading the ener thread it seems that also has issues!

So sounds like the Lead Acid battery advice was not a thing in UK as even early Model Y’s were Li.

But earlier post that I missed when answering showed it to be much more of a lottery.

Hopefully an older module could be retro fitted? That will more likely get a positive response than waiting on Tesla to implement something in software, or not, as it sounds like it’s missing the appropriate hardware.

Might be worth checking epc.tesla.com for versions of the module.

The M3 has never had anything above pin 8 wired up, so it only runs the essentials and no auxiliaries. The MY has wavered between offering the higher pins and not. At one point the modules they were providing did offer auxiliary switched and live, however the latest modules don’t seem to offer this. The manual even states it may or may not work.

Model Y Owner's Manual | Tesla

Learn how to safely use your vehicle to carry accessories and tow a trailer.

www.tesla.com

View attachment 966442

 

[qwickshot]

Hello All,

just picked up my MY RWD with Towbar factory fitted, and the electrics don’t work. Tested the connection and it doesn't have a Live feed or a switched live for charging the caraavan fridge etc.

Raised a service request and they very quickly came back with " pins 9-13 aren’t enabled in the new Li-Ion aux battery versions. Tesla are working on a fix but don’t know if it will be HW or SW!"

The reason the pins arent currently enabled is cause they don’t know how the Li-ion battery will react with caravan/trailer electrics and vice versa!

So it seems like an unknown wait period! Considering the reason we leased the car was to two our caravan in the 1st place!

The Lease company is now involved!

Tesla Remote Techician mentioned that it would work with an old Lead acid battery. Can anyone confirm that? Reading the ener thread it seems that also has issues!

Plenty of us tow caravans with the Model Y and since the switch to using a 16V lithium low voltage battery, there has been no permanent 12V feed to the tow bar electrics.

The lights all work fine the only thing that doesn’t get powered is the fridge or any ATC type product if you have it installed.

Most owners just write off the fridge as the 12V feed doesn’t actually cool the fridge down if it’s not been pre-cooled off mains/gas. The 12V feed makes is just barely enough maintain temperature. An ICE pack generally does a better job.

ATC is slightly different, most owners get it re-wired to be powered off the onboard leisure battery via an on/off switch. Most caravans don’t even have it fitted (mine doesn’t) and not something I’d be particularly concerned about. An EV makes for a very stable towing platform due to the low centre of gravity. If you load the van correctly, it should never ever kick in.

The model Y makes a great towing platform and the lack of pertinent 12V feed from the car isn’t a deal breaker for me or even unique to Tesla.

 

[Paul Thomas]

Whether this is the same with Model Y I do not know. Were Model Y’s ever fitted with MCU2, ie 12v battery? I thought they all came with Ryzen and Li battery.

This is taken from the current manual and would appear to indiate that there are versions with the Lead Acid battery out there!


"Vehicles with a lead-acid low voltage battery have auxiliary power. Vehicles with low voltage lithium-ion batteries do not have auxiliary power at this time. You can determine which battery your vehicle is equipped with by touching Controls > Software > Additional Vehicle Information."

 

[GeorgeSymonds]

This is taken from the current manual and would appear to indiate that there are versions with the Lead Acid battery out there!


"Vehicles with a lead-acid low voltage battery have auxiliary power. Vehicles with low voltage lithium-ion batteries do not have auxiliary power at this time. You can determine which battery your vehicle is equipped with by touching Controls > Software > Additional Vehicle Information."

Manual covers Europe and it launched there about 6 months earlier than we got it before Ryzen and the Li Ion battery

 

[Paul Thomas]

ATC is slightly different, most owners get it re-wired to be powered off the onboard leisure battery via an on/off switch. The lights all work fine the only thing that doesn’t get powered is the fridge or any ATC type product if you have it installed.

Thanks Qwickshot, is that a simple thing to do? Who would?

The lights all work fine the only thing that doesn’t get powered is the fridge or any ATC type product if you have it installed.

Sadly, non of the lights work which makes it illiegal in the UK [ I think!] They are all LED.

If you have some suggestion of what can be done to fool the car I'm all ears!

Thanks in advance.

 

[qwickshot]

Thanks Qwickshot, is that a simple thing to do? Who would?

Caravan service technician can do it or DIY, probably the former.

Sadly, non of the lights work which makes it illiegal in the UK [ I think!] They are all LED.

If you have some suggestion of what can be done to fool the car I'm all ears!

Thanks in advance.

Have you got an older or newer caravan and has it been modified at all from it’s original specification?

My caravan is a 2023 and has all LED lights, I plugged in the 13 pin connector and the lights worked without issue.

Some caravans had to be modified when they switched to LED lights as cars that were not built around LEDs couldn’t detect the bulbs and had issues. The resolution was to install a module to fool the car that the lights were all there and working.

When a car gets plugged in that’s expecting LED lights, these modules then cause issues.

I don’t think many people tow on here so I’d suggest joining the ‘caravanning with electric vehicles’ group and ‘EV caravaners’ group on Facebook - lots of model Y owners in both those groups.

Tesla also have LED light boards in the service centre to test the tow hitch electrics - a service call may be the way forward if you can’t get the lights working.

 

[Cardo]

Thanks Qwickshot, is that a simple thing to do? Who would?



Sadly, non of the lights work which makes it illiegal in the UK [ I think!] They are all LED.

If you have some suggestion of what can be done to fool the car I'm all ears!

Thanks in advance.

Pins 1-8 are wired in, which control the lights. So they should be working with the Tesla towing electrics, no matter which revision you have. If your caravan lights aren’t working, you’ll want to make sure things are working on both the car and the caravan.