"All Wheel Drive Permanently Engaged" & "Motor Fault Detected"; Will not drive w/o reboots

[Brian-MS90D]

Picked up new R1S Dual Motor Max on Sunday. Left Monday for long road trip vacation. Absolutely love the vehicle. However, starting Monday I noticed a troubling issue. Whenever the car goes to sleep, upon re-entering and trying to drive it gives the following errors (in order):

It then will not shift into Drive or Reverse. Binnacle will not say "Ready." Additionally, the HVAC will not turn on (all other functions work such as lights, radio, frunk/truck, etc).

In order to clear it, I have to do two of the three "reboot" methods. The method that works the most reliably is:

1. "Sleep reboot" - Turn off proximity key, bluetooth, and WIFI. Lock the car and ensure nothing on the seats, no USB plugged in, and nothing connected to charge port. Wait ~ 15 minutes for the car to complete a sleep cycle.
2. "Hard reboot" - Left steering wheel button + hazard button reboot. During the reboot, many things click around the car and behind the dashboard.

After the hard reboot, the car works normally and I can shift into Drive.

Additionally, the car works normally as long as I do not let it sleep. For example, if charging (DC or AC) has not completed then the faults will not come up. I used this to my advantage last night overnight at hotel by lowering the amps and creating a very long charge time so that when I came back to the car in the morning it was still charging. Or, if I leave dog mode on while at a restaurant that will prevent the car from sleeping and avoid the faults.

I have also noticed that I cannot remotely control the climate from the Rivian phone app. Even when the car is functioning normally if it has not gone to sleep yet, it never "connects" to turn on/off or modify the climate settings. That being said, I can monitor the charge status remotely from the app.

If I only try to do a hard reboot (without the sleep reboot), during the reboot the car does not make the clicking noises around the car and behind the dashboard. The faults will remain. I can only clear the faults by doing the combination of the two reboots (and it appears in any order, although I have not fully proved this out yet).

Once operational, everything is normal. I've observed and confirmed that both motors are engaged at low speed. And, that only the front motor is engaged at highway speed. I've driven ~ 600 miles now over 2 days despite these faults that are generated when I allow the car to sleep.

Rivian phone support had no ideas. They scheduled me with a service appointment for Monday when I return home (assuming my reboot scheme works for the rest of the week). I haven't read anything like this in the forum or elsewhere online.

Has anyone seen this or have any ideas?

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[Joefly78]

I get the AWD error from time to time. I suspect it happens when I jump in the car and shift into gear too quickly. When I intentionally give it more time to boot up it has never happened. SC had no clue as to cause. Never got the second message you're seeing.

 

[240vPlug]

rear motor disengages itself above 20mph to get max efficiency. It would appear there is some issue with either the motor or the ancillary electronics that allow this feature to function.

 

[Zoidz]

These are both DM vehicles, right? Based on your descriptions, it would not surprise me at all if this is just a software bug specific to that architecture.

 

[Move]

My DM R1S is in service right now being diagnosed for this exact error. Waiting on field techs to determine what might be wrong.

 

[Brian-MS90D]

@240vPlug , I agree and have been watching this. At least according to the interface graphic, this is occurring correctly. Only front motor is driving above ~ 20mph. Both motors are driving below. And, if I stomp on the accelerator both motors will drive until that hard acceleration is over at which point only the front motor drives.

@Zoidz , yes, Dual Motor (non-performance for me). In my opinion it does seem to be a bug, but the counter argument to that is it doesn't appear to be prevalent (at least by my searching online). My amateur theory is something is not coming out of sleep mode properly.

@Move , I'm "glad" to see I'm not the only one! Did yours happen immediately within a day or so of delivery like mine? Or did it develop some time after? Please do let me know how they resolve it!

 

[pangpang77]

I got the motor fault error and had it in the shop. They replaced a motor drive sensor and haven’t had an issue since. Annoying and scary that it would stall at any point when I had the issue. Hard reboot would clear it as well until they replaced the sensor.

 

[240vPlug]

I got the motor fault error and had it in the shop. They replaced a motor drive sensor and haven’t had an issue since. Annoying and scary that it would stall at any point when I had the issue. Hard reboot would clear it as well until they replaced the sensor.

Makes sense...since the engagement/disengagement is based on speed, traction, and load.

 

[Move]

@240vPlug , I agree and have been watching this. At least according to the interface graphic, this is occurring correctly. Only front motor is driving above ~ 20mph. Both motors are driving below. And, if I stomp on the accelerator both motors will drive until that hard acceleration is over at which point only the front motor drives.

@Zoidz , yes, Dual Motor (non-performance for me). In my opinion it does seem to be a bug, but the counter argument to that is it doesn't appear to be prevalent (at least by my searching online). My amateur theory is something is not coming out of sleep mode properly.

@Move , I'm "glad" to see I'm not the only one! Did yours happen immediately within a day or so of delivery like mine? Or did it develop some time after? Please do let me know how they resolve it!

No, happened after 2 months of ownership and after I received the battery fault which appears to be the 12V system issue. They replaced the 12V and are now working on diagnosing the motor. Will update when I know more.

 

[defcon888]

I get the AWD error from time to time. I suspect it happens when I jump in the car and shift into gear too quickly. When I intentionally give it more time to boot up it has never happened. SC had no clue as to cause. Never got the second message you're seeing.

I agree. We had the 12v battery issue and the service person on the phone said that after I charge it and unplug and then get in the truck, wait a few seconds before you engage the drive or reverse.

I listened to him and charged to 90% and put the R1T to sleep and the next morning, the 12v battery issue was gone. I did have a ticket in to have it looked at. The mobile tech came out and replaced the battery even though the error went away. He said that it was only at 8v.

 

[Move]

Getting my R1S back today. Being told the 4x4 notification at the startup is going to be fixed on a future firmware update and that the vehicle is operating as it should other than the temporary notification.

 

[Brian-MS90D]

Getting my R1S back today. Being told the 4x4 notification at the startup is going to be fixed on a future firmware update and that the vehicle is operating as it should other than the temporary notification.

Interesting...
When you say you had the "exact same error," would it also prevent you from shifting into gear and driving (as it does for me)? Or, was it just a pesky alarm that persisted, but you were still able to drive?

If it's the exact same as what I'm experiencing, your outcome is very disheartening because at any give time it can take me ~ 15 minutes to get the vehicle operational (by the time I wait for a sleep cycle and then do a full reboot). Although, the counter argument would be that at least it's not a serious hardware issue and they won't be ripping the whole drive train apart for a repair.

 

[Move]

I'm getting the same error, but not preventing me from doing anything.

 

[Brian-MS90D]

UPDATE: Dropped R1S off to service center on 4/1. I was updated today that the front drive unit is being replaced. Expected to be ready for pick up on Wednesday (4/10). I was surprised with that because in my amateur experience I guesstimated this was going to be a sensor replacement or something (since reboots "solved" the problem).

The R1S has been in service more days than I've had it , but I'm not overly upset and know that this is often par for the course with niche, low annual production volume vehicles. I've had similar experiences with my previous Tesla Model S, Land Rover LR, and others. Hopefully when I pick it up everything will be working great and I can get back to enjoying this awesome vehicle.

And, hopefully if others encounter this exact symptom in the future this serves as useful information regarding how to temporarily clear the alarms.

 

[Brian-MS90D]

The R1S is back with me and working well so far (other than apparently well known steering wheel left of center, which I'm just going to live with for now). The repair report is actually fairly detailed.

Primary cause/failure was the FDU inverter. This required the replacement of the ENDURO front drive unit. According to the report this took 2 hours of labor.

They also successfully fixed my rattling dash speaker grill. The description was "removed the dash grill and added the missing noise isolation foam." I thought the inclusion of the word missing was interesting.

Anyways, this will be my last update.

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