Gen 1 Vampire Drain (Possibly) Solved (or Hacked)

[Yossarian]

Glad I found this message and confirming this may be true. Vampire drain was never an issue for me - maybe 1% every 2 to 3 days - until my vacation last week where the car sat at home for 6 days, unplugged at 72% SOC. From the app I could see it was losing 1% a day, which I thought was strange. Came back from vacation (65% SOC) and charged it with no issue. Drove it for a day, then it sat for two days at around 70% SOC and seemed fine...until today when I went to unlock it and the Service 12V Battery notification popped up on the app; the car was completely dead. Jump started it through the trailer hitch which got the doors to unlock and screens to come on, but charge port door and frunk would not open via the external buttons or through the app (greyed out). Towed to the SC and I'll see what they say tomorrow.

A few things of note:

- When I plugged it in after coming back from vacation, the car started charging immediately despite it having a schedule set for later that evening. The vehicle had never charged outside of its schedule before. It did stop after like a minute then proceeded to charge normally later that night during the schedule.

-When I got back from vacation the vehicle was down to its bump stops in the front, but fine in the back.

-When I jump started the car only the driver side windows would go down.

Is the change in parasitic drain that you note after installing the the 2024.27.01 update?

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[PBRAZ]

Is the change in parasitic drain that you note after installing the the 2024.27.01 update?

If that's the latest one with Apple Music, etc, then no, I haven't installed that update yet.

 

[Yossarian]

I think the formal statement is 2% per 24 hours, that is huge IMHO. This was confirmed by Wassym Bensaid on his last call. Anything above 2% - you can open a ticket and challenge Rivian support. But as far as I see - most of GEN1 cars are averaging between 1% and 1.8% per 24 hours.

For a long time, we suspected that charging a 12V battery is what caused this drain. I think this thread is confirming that.

Do you have a link to the call or the call transcript of Wassym referencing the 2%/24 hr parasitic drain parameter? I can't seem to find anything online and would like to have something in my back pocket to counter "up to 12% daily is within normal limits" line that Rivian service has referenced when I put a service ticket in for the 4%/24 hrs that I'm seeing.

Apologies to the OP for this diversion.

 

[shap]

Do you have a link to the call or the call transcript of Wassym referencing the 2%/24 hr parasitic drain parameter? I can't seem to find anything online and would like to have something in my back pocket to counter "up to 12% daily is within normal limits" line that Rivian service has referenced when I put a service ticket in for the 4%/24 hrs that I'm seeing.

Apologies to the OP for this diversion.

In a video https://x.com/klwtts/status/1781714340686795192 in April, Wassym Bensaid mentioned that the expected idle drain for the car should be an average of 1 mile per day [12:59].

He later mentioned that he was talking about % and not miles, but still, 1% max per 24 hours.

 

[shap]

BTW, what I see is something else that started to happen with the update (not the very last one that I still waiting for) :

While SoC is going down sharply, Capacity is going up sharply. They changed something in how BMS is managing the battery and we see all these anomalies.

I added a new sensor to Home Assistant - Capacity / SoC - to see if this proportion changes as well. I think it is a better indicator of phantom drain for now.

 

[Yossarian]

Thanks @shap . Hope you figure out what's going on with your vehicle.

Until the update, I had been seeing a 1% to 2% loss over 24 hours. After the update, I'm now seeing at least double that. When I added the parasitic drain to the work order for my December service appointment, Rivian told me that though they'll take a look, up to 12% is considered acceptable. While that's obviously nonsense, having something official from Rivian that helps refute that should help.

 

[HyperionMark]

Anyone try charging through 7 pin or other 12v "cigarette lighter"?

 

[NY_Rob]

Data point:

I haven't touched/entered/communicated via the phone app with my R1T since Sun afternoon. It was indicating 146 mi range on Sunday, I've had my trickle charger running since then. It's now been 5 full days since then, just went out to check... 144 mi range indicated.

Lost just 2 mi range over 5 full days with the NOCO trickle charger running

 

[josh0]

The 2024.31 update does seem to have improved things. It took about 30 hours for my SoC to drop by 1% simply parked on the street with gear guard on and connected to WiFi.

 

[NY_Rob]

^ that's good to hear, I'm still on the previous update, you know the one that doubled VD for lots of Gen 1 owners

If the trickle charger, which I previously tracked and calculated costs under $2/month to run, can keep VD to 2mi loss/week I'd be a happy camper.

 

[Yossarian]

It's only been a day since I downloaded the update, but my parasitic drain over a full 24 hours was only 2%. While that's still too high for my liking, and is double the 1% that Wassym references as Rivian's goal, it is quite an improvement over what I was seeing previously.

On a related note, I wonder if there is any way to make Rivian aware of this thread in general, and specifically of the results of the experiments that folks like @NY_Rob ran. It seems pretty clear that keeping the 12v storage battery topped up has quite a positive impact om parasitic drain. Surely the Rivian teams can figure out a way to have the traction battery do a better job keeping the 12v system charged. Perhaps Rivian already knows that however, and it's just too hard to make that kind of change?

 

[NY_Rob]

It seems pretty clear that keeping the 12v storage battery topped up has quite a positive impact om parasitic drain. Surely the Rivian teams can figure out a way to have the traction battery do a better job keeping the 12v system charged. Perhaps Rivian already knows that however, and it's just too hard to make that kind of change?

To be frank, I don't think they are actively trying to get VD down to almost zero. Like any big/complex project, you solved 99 out of 100 issues, and you have to launch with that otherwise you will never get to market. I think they're resigned to the fact that Gen 1 vehicles have parasitic drain period. As long as they keep it down under 2% owners won't revolt and life goes on.

If they could line that big, beautiful roof with flexible solar sheeting (Fisker Ocean One), it might be enough to keep a sufficiently sized 12V battery charged so that the vehicle wouldn't need to use/drain the 400V battery to recharge the 12V battery.

 

[Tim-in-CA]

To be frank, I don't think they are actively trying to get VD down to almost zero. Like any big/complex project, you solved 99 out of 100 issues, and you have to launch with that otherwise you will never get to market. I think they're resigned to the fact that Gen 1 vehicles have parasitic drain period. As long as they keep it down under 2% owners won't revolt and life goes on.

If they could line that big, beautiful roof with flexible solar sheeting (Fisker Ocean One), it might be enough to keep a sufficiently sized 12V battery charged so that the vehicle wouldn't need to use/drain the 400V battery to recharge the 12V battery.

Yes, I've resigned myself that VD will probably never be much better than ~1% on Gen 1. Would be good if Rivian published an official method to keep 12V topped up as that appears to be the root cause of the VD for G1. Like you (and myself), I‘m sure that there are others that keep their Rivian garaged for a period of time without driving. If I had a super cheap electrical rate or lots of extra solar capacity, I wouldn't complain. But as it is, VD consumes approx 50% of my excess production (currently ~100% with the current bug) and rates in So Cal (SCE) are pretty high and only going UP!!!

 

[mkhuffman]

Yes, I've resigned myself that VD will probably never be much better than ~1% on Gen 1. Would be good if Rivian published an official method to keep 12V topped up as that appears to be the root cause of the VD for G1. Like you (and myself), I sure that there an others that keep their Rivian garaged for a period of time without driving. If I had a super cheap electrical rate or lots of extra solar capacity, I wouldn't complain. But as it is, VD consumes approx 50% of my excess production (currently ~100% with the current bug) and rates in So Cal (SCE) are pretty high and only going UP!!!

I wonder if replacing the 12V battery with one that has higher capacity would help? It seems to me the root cause is all the system activity that is draining the 12V battery, which requires the HVB to keep it from dying. A battery that has a slower drop in SoC might make a measurable difference in VD.

Just a thought.

 

[Tim-in-CA]

I wonder if replacing the 12V battery with one that has higher capacity would help? It seems to me the root cause is all the system activity that is draining the 12V battery, which requires the HVB to keep it from dying. A battery that has a slower drop in SoC might make a measurable difference in VD.

Just a thought.

Yes ... any official recommendations that Rivian could provide would be great. It is befuddling to me why many EV manufactures followed Tesla's "lead" by putting small 12V lead acid batteries in their vehicles (Tesla has subsequently changed to Lithium Ion I believe). 12V car batteries have been a known element for decades and cheapening out here (actually they seem to be even MORE expensive than traditional car batteries) was the wrong direction.

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