[CotoR1TDude]

I'm posting a new query on the R1T's 12v system, as the previous one was old and it was recommended to start new.

There is a lot of interest in 2-way radios and accessories in the various posting. I want to install a 2-way radio, a radio that is normally connected to a conventional vehicle's 12 volt battery system, and operate at 13.8 volt and require 12A continuous (A vehicle battery system is considered 12V nominal when the vehicle is off and 13.8V nominal when the vehicle is running). I plan on mounting the radio below the vents below the dash... right next to a 12v outlet. Does anyone have any insight into Rivian's 12 volt system. Will we have the same capability that conventional vehicles provide when connecting to the 12 volt systems to get 13.8 volts?

I've seen posts about people wanting to use the 12 volt system with a winch, and reference to the 12 volt systems supporting trailer with 40 AMP. I just want to start with a GMRS radio for my overlanding. Again, any insights would be greatly appreciated.

 

[O. horridus]

I measured the voltage on my R1T's 12V frunk outlet and it's 14.33V for me right now. Lead-acid batteries are charged with a voltage higher than the nominal 12.6V of the 6 lead-acid cells used by a car battery (2.1V per cell), so I suspect my vehicle is charging the batteries right now. I'll measure again later.

EDIT: I just realized this higher voltage might be a sign that Rivian is using AGM batteries.

Automobile electronics that run off of "12V" are designed to accept a voltage higher than 12V, and they are built really robustly so that over-voltages don't damage them. 12V on an ICE vehicle is very noisy - it's not a clean and even 12V, it spikes really high due to the all the transients running through the system. I expect the 12V on the Rivian to be a lot cleaner.

The limitation of the 12V system on the Rivian is going to be the two small batteries - you can't draw as much current from them as you can from one of those big ICE batteries. In general you don't need to either - no starter motor, etc. that needs a high current. Running a winch off those two small batteries is probably not going to work, but a radio should be no problem at all.

 

[CotoR1TDude]

Thanks. Can you measure the 12v inside the cab too? I don't know if it's a safe assumption they will be the same. I'm assuming the R1T has the ability to control the 12 V outlets on/off behavior in the different modes - vehicle on/off/accessory mode - If you have knowledge on this let me know.

I'm going to use the 12 volt outlet in the front cab and mount the radio in front of it. I'll use an adapter like this https://www.amazon.com/Apoi-Cigaret...dp/B08B5Y9H6G/ref=psdc_15729631_t3_B071P3RX8G to plug/play. This way I can use the radio on my eBike

 

[O. horridus]

I measured again. The frunk, under front dash, and gear tunnel outlets are all at 13.58V right now.

I believe the 12V is always on. The only control from the screen is to turn on/off the 120V outlets.

 

[Frisbee]

FYI. The 12v outlet under the dash in the cab times out after about 10 minutes of the vehicle’s non use. So far Rivian has not disclosed any information about the vehicle’s fuse boxes one of which is located under the dash on the passenger side. There is supposed to be a second one under the dash on the driver’s side but I have not confirmed that.

 

[CotoR1TDude]

I measured again. The frunk, under front dash, and gear tunnel outlets are all at 13.58V right now.

I believe the 12V is always on. The only control from the screen is to turn on/off the 120V outlets.

Thanks. Hopefully, that will be the ticket. Is it possible given the nature of the cigarette plug it loses some voltage?

 

[CotoR1TDude]

FYI. The 12v outlet under the dash in the cab times out after about 10 minutes of the vehicle’s non use. So far Rivian has not disclosed any information about the vehicle’s fuse boxes one of which is located under the dash on the passenger side. There is supposed to be a second one under the dash on the driver’s side but I have not confirmed that.

This is very interesting and significant. I’ll discuss with the guide.

 

[azzurro]

This is very interesting and significant. I’ll discuss with the guide.

Thanks. Hopefully, that will be the ticket. Is it possible given the nature of the cigarette plug it loses some voltage?

FYI. The 12v outlet under the dash in the cab times out after about 10 minutes of the vehicle’s non use. So far Rivian has not disclosed any information about the vehicle’s fuse boxes one of which is located under the dash on the passenger side. There is supposed to be a second one under the dash on the driver’s side but I have not confirmed that.

Other than the cigarrete lighter outlet under the center of the dash there is no other 12V power source inside the vehicle. you could use one of this depending on your amp draw....

Universal OBD2 Diagnostic Tool Car Cigarette Lighter 16 Pin Socket Power Adapter | eBay

 

[farmedb]

Other than the cigarrete lighter outlet under the center of the dash there is no other 12V power source inside the vehicle. you could use one of this depending on your amp draw....

Universal OBD2 Diagnostic Tool Car Cigarette Lighter 16 Pin Socket Power Adapter | eBay

I don't know about the rivian, but the prius has a 7.5a fuse on the ODB2 circuit. That is about 90 watts. I would be afraid of blowing the fuse.

 

[azzurro]

I don't know about the rivian, but the prius has a 7.5a fuse on the ODB2 circuit. That is about 90 watts. I would be afraid of blowing the fuse.

 

[CotoR1TDude]

Other than the cigarrete lighter outlet under the center of the dash there is no other 12V power source inside the vehicle. you could use one of this depending on your amp draw....

Universal OBD2 Diagnostic Tool Car Cigarette Lighter 16 Pin Socket Power Adapter | eBay

Sorry, I don't understand how to apply this. Can you elaborate? Does this plug into the fuse panel in some way? Is this some inside baseball Rivian employee dropping an Easter egg Sorry, I'm lazy and people have to spell it out to me.... while I focus on my job that allowed me to drop $80K on vehicle. (Humor goes here).

Thanks!

 

[azzurro]

Lol. Not an Easter egg. Look under the dash Driver's side to the left of the brake pedal
You will find the OBD connector

https://findandfundmycar.com/articl...The OBD port is a,of on-board computer system.

that's where you plug this adapter to get 12V

 

[CotoR1TDude]

Thanks! I've seen at least one video where the phone carger comes from the left (Rivian utube channel guy). this makes sense. Thanks for the great tip!!!