Phantom / Vampire Drain Solution Works! Using 12v Battery Tender

[chops]

latest 2024.10 has increased my drain to 1%/day again, even with a 5A tender. what the hell is going on rivian!!

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[mudito]

latest 2024.10 has increased my drain to 1%/day again, even with a 5A tender. what the hell is going on rivian!!

I would try a full reset. 1% with a 5A tender is a lot.

 

[sacramentoelectric]

Thanks to everyone who’s contributed to cracking the vampire-drain problem – I finally seem to have solved it (at least on my end). Below is my setup and the results of an eight-day test. I added links to all the items in my setup.

Result: 1 % total vampire drain on the high-voltage pack over eight full days parked while I was out of the country. 6 kWh consumed from my external LiPo battery system that lives in the bed that powers the 12v OBD charger. 2023 R1T Version 2025.10.01. Parked outside in moderate weather.

I know it’s pretty convoluted (and absurd that we have to go to these lengths!), but if you’re heading off-grid for a while, this works really well.

My chain of components:
OBD battery-tender connector
→ 12ft SAE extension cable
→ wire routed along the floor then behind the back seat through the tonneau-cover cavity (I don't have a powered tonneau.) It exits in the bed. (if you have the powered cover, route around the felt in the gear tunnel)
→ 3Amp Battery-Tender charger
→ small 12v DC→110v AC converter (the smallest you can find.) I had an old one lying around so no link for this. You could plug the battery tender into the ac ports on your power station but they will consume more power than using a small external converter via the dc jack. You only need around 35watts of 110v power to power the obd tender.
→ EcoFlow Delta 2 Pro power bank (2kw)
→ EcoFlow alternator charger
→ two 150 Ah, 12 V LiPo batteries in series

When I charge my Rivian, I turn on the outlets. That charges my Ecoflow in the bed which charges my external LiPo batteries using the Alternator charger. When it's done charging, I switch the alternator charger to pull power from the external batteries to charge the Ecoflow. That gives me about eight days of power for the OBD battery tender.

Instead of losing around 20kw of power from the high voltage pack to vampire drain over eight days, I lose 6kw from my LiPo external system. Of the course of a year, that's about 640kWh in savings. What an embarrassingly stupid waste. The side benefit of this system is that it also gives me a much more efficient power supply when I'm out camping. Keeping the Rivian's 110v outlets on wastes a huge amount of power at idle.

 

[DayTripping]

Great outcome but a creative yet convoluted solution. Sad you had to go to such lenghts. At the same time, it is absolutely ridiculous that we have to do this to minimize vampire drain. I had no idea how bad it really was until I owned my truck.

The 2 worst surprises of my ownership experience have been the damn wind noise at higher speeds and the vampire drain. Ok, maybe add a 3rd terrible thing; Driver+. Maybe they should rename it to Driver- (Driver Minus).

 

[sacramentoelectric]

Great outcome but a creative yet convoluted solution. Sad you had to go to such lenghts. At the same time, it is absolutely ridiculous that we have to do this to minimize vampire drain. I had no idea how bad it really was until I owned my truck.

The 2 worst surprises of my ownership experience have been the damn wind noise at higher speeds and the vampire drain. Ok, maybe add a 3rd terrible thing; Driver+. Maybe they should rename it to Driver- (Driver Minus).

I know. It's nuts. The vampire drain has infuriated me from day 1. The amount of waste is scandalous, especially from a brand that likes to tout its environmental responsibility. There are so many awesome things about the truck, I just can't believe they screwed this up so badly.

I had the Ecoflow anyway and got a crazy deal on the lipo batteries to the overall cost wasn't that high. It's nice having the extra capacity for camping but the truck is a giant battery anyway so none of this should really be necessary.

My wind noise was really awful until the replaced the seals on my driver door. I had to ask twice but the little corner window isn't bad anymore. Driver+ is an embarrassment and was my least favorite thing about my Rivian but Openpilot has me falling in love with it all over again. Once the PlayEV adapter ships next month, I'll be able to fix my last real gripe (no carplay.)

 

[DayTripping]

Comma.Ai is probably the most likely reason I will keep my truck at this point. I have made progress on the wind noise, and it is going back in to reset the appliqué in front of the pano roof. Hopefully that will take care of it.

I agree with the inexcusable part for the drain given how they position themselves in the market. Collectively we are wasting millions of dollars annually on electricity!!!!!! WTH?

I am also waiting on EVPlay as well. My topper is going on tomorrow, with any luck I'll pretty much call it a day with truck mods, at least when I set up my AirCruiser RTT at some point.

There have been a few weeks dealing with the wind noise, the vampire drain and the Driver- that I was just ready to sell the truck and seriously consider a CT again or even Silverado.

Then I got my Comma.Ai installed, I made some progress on the wind noise. Set up a battery tender through the OBD or my solar cell through the OBD port, my topper showed up, and next thing you know I am so deep in the damn ecosystem it becomes more expensive to unwind my position every week. At least now with the add-ons and fixes, I have mitigated some of the issues but it has been very frustrating what I've had to do.

If I went to the extent you did, that probably would have pushed me over the edge. For me the truck is about 85-90% great, but that other 10% is almost intolerable.

 

[DayTripping]

I had a chance to test out the battery tender solution on my R1T. I was gone for 8 days. I left a 3 amp battery tender plugged in via OBD port. I just locked my truck and did nothing else but I do have proximity unlocking turned off at home. When I left I was at 49.70% according to Electrafi. When I returned and checked again, I was at 49.2%.

My truck pretty much slept the entire time except for about 1 min a day I lost .4% when I was trying to adjust the charging window for when I came home. So for a Gen 1 truck, that works out to about .05% per day loss but most of that was due to the truck being on. According to Electrafi, there was no vampire drain during the period I was gone. I'd call that a major success.

 

[hammick]

https://www.rivianforums.com/forum/threads/trick-for-maintaining-health-of-the-12v-battery.37720/

That's my "trick" that I do every now and then. I don't do OBD, I have a direct wire setup (explained in the post) and my R1T sleeps peacefully for 14-16 hours every day without waking up. I need to stress that a good battery tender does more than just charge but also reconditions the battery. That's KEY to me

Yep. Lot's of people think desulphation or recondition mode is snake oil but 12 years out of the battery in our John Deere tractor using a Battery Minder .75a with the automatic desulphation says otherwise. If it wasn't mowing it was on the tender. The newer model is 1.5a and has temp compensation.

I have a handful of friends that I've recommend buy this $50 tender for their lightly used motorcycles, tractors, cars, etc. Most of them ignore the advice and pay a couple hundred buck a year to replace the batteries in their lightly used stuff The one's with lots of toys probably spend over a grand on batteries every few years. They also believe you can just let a vehicle idle for a half hour to recharge the battery. Not good for the engine and the battery probably doesn't recover the AH it took to start it.

 

[SSteveEV]

I had a chance to test out the battery tender solution on my R1T. I was gone for 8 days. I left a 3 amp battery tender plugged in via OBD port. I just locked my truck and did nothing else but I do have proximity unlocking turned off at home. When I left I was at 49.70% according to Electrafi. When I returned and checked again, I was at 49.2%.

My truck pretty much slept the entire time except for about 1 min a day I lost .4% when I was trying to adjust the charging window for when I came home. So for a Gen 1 truck, that works out to about .05% per day loss but most of that was due to the truck being on. According to Electrafi, there was no vampire drain during the period I was gone. I'd call that a major success.

Just to clarify, do you mean the OBDII Battery Tender adapter, or do you have a battery tender hooked up directly to one or both of the batteries?
Thanks, that's a great result!

 

[DayTripping]

Just to clarify, do you mean the OBDII Battery Tender adapter, or do you have a battery tender hooked up directly to one or both of the batteries?
Thanks, that's a great result!

I should have been more clear. I just ran a 3 amp battery tender through the OBD port. I was totally shocked. Ad another day to my post. The battery level hadn't budged since yesterday when I checked and finally had to charge and drive the truck.

 

[SSteveEV]

I should have been more clear. I just ran a 3 amp battery tender through the OBD port. I was totally shocked. Ad another day to my post. The battery level hadn't budged since yesterday when I checked and finally had to charge and drive the truck.

Awesome, now we just need to figure out which 12v system (if any) is the main vampire, and unplug that so we don't need battery tenders constantly.

I'd happily install a physical switch for my 4G connection somehow if that is the main culprit for when I travel or park long term. But alas I assume that'll be too upsetting to my truck with all it's data needs.

 

[MacO512]

Awesome, now we just need to figure out which 12v system (if any) is the main vampire, and unplug that so we don't need battery tenders constantly.

I'd happily install a physical switch for my 4G connection somehow if that is the main culprit for when I travel or park long term. But alas I assume that'll be too upsetting to my truck with all it's data needs.

That would be great if there's were some simple accessories that could be turned off.

My suspicion is it's the whole system and not just some individual component. Also disconnecting power to some modules might throw error codes.

If vampire drain could be fixed in software I think Rivian would've done it. IMO it's their over engineered hardware, along with the tiny 12v. It's a fantastic vehicle but I think this is just a downside of a new startup making a high quality - but very complex first vehicle.

I'm all for someone else being the guinny pig experimenting with turning off certain ECUs to try and locate the VD culprit. Please let us all know if you do!

 

[Aardvark]

I had a chance to test out the battery tender solution on my R1T. I was gone for 8 days. I left a 3 amp battery tender plugged in via OBD port. I just locked my truck and did nothing else but I do have proximity unlocking turned off at home. When I left I was at 49.70% according to Electrafi. When I returned and checked again, I was at 49.2%.

My truck pretty much slept the entire time except for about 1 min a day I lost .4% when I was trying to adjust the charging window for when I came home. So for a Gen 1 truck, that works out to about .05% per day loss but most of that was due to the truck being on. According to Electrafi, there was no vampire drain during the period I was gone. I'd call that a major success.

Excellent result...thank you for the update. I am getting very good results with my 2 amp Noco Genius 2, but haven't had a chance to test it over a long, multi-day period. I'm happy with my short term results so far.

By the way, thank you for spelling out "vampire drain." When I see folks complaining about their "VD" problem, I keep thinking they should be on WebMD.com, not the Rivian forum.

 

[SSteveEV]

My suspicion is it's the whole system and not just some individual component. Also disconnecting power to some modules might throw error codes.

If vampire drain could be fixed in software I think Rivian would've done it. IMO it's their over engineered hardware, along with the tiny 12v.

Agreed on the codes unfortunately.

Also half agree on the software, they have acknowledged they messed up Gen1 by having to wake all modules at once. I think they could do better but are still trying to attack it from the jack of all trades master of none compromise.
What I'd love to see is a "energy sipper mode" where it minimizes drain depending on what you select from a list of items that cause drain. This would be a detrimental user experience but would allow us to pick how much (if at all) we want to suffer for the savings.
Ie, not everyone cares about drain and wants HVAC to stay enabled constantly. I turn HVAC off, radio off etc when parking for a long time. If I had the option to turn off wifi forever I would. As mentioned, turning off 4G would be an option sometimes.
There is an easy 20+ items that could be hot linked to one press on the main screen next to the lock button. Call it "super lock" or "ElectroPark" and bury it deep deep in the settings so only the Battery Tender crowd bothers to enabled it

 

[MacO512]

Agreed on the codes unfortunately.

Also half agree on the software, they have acknowledged they messed up Gen1 by having to wake all modules at once. I think they could do better but are still trying to attack it from the jack of all trades master of none compromise.
What I'd love to see is a "energy sipper mode" where it minimizes drain depending on what you select from a list of items that cause drain. This would be a detrimental user experience but would allow us to pick how much (if at all) we want to suffer for the savings.
Ie, not everyone cares about drain and wants HVAC to stay enabled constantly. I turn HVAC off, radio off etc when parking for a long time. If I had the option to turn off wifi forever I would. As mentioned, turning off 4G would be an option sometimes.
There is an easy 20+ items that could be hot linked to one press on the main screen next to the lock button. Call it "super lock" or "ElectroPark" and bury it deep deep in the settings so only the Battery Tender crowd bothers to enabled it

Yeah I just don't know it's possible for a mode that disables some items, I suspect the computer needs to be on or off and that causes the drain. To turn it off I believe they already have shipping mode. If anything they should just improve that mode so it uses as few watts as possible and advanced users could just use that.

Possibly a part of the issue is there is no physical key. So they can't ever shut off the sensors for locking or it somewhat "bricks" the vehicle. Maybe they don't have any low powered computer to run those sensors.

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