Yes I have experienced this as well.
I believe you are correct- the message basically is saying that the car automatically takes the Emergency Parking Brake off when you shift out of park as per your settings.
My guess (and it is just a guess) is that it is just a reminder and as such, as you call it, "a harmless nuisance". I could be wrong though, and if you find out otherwise I would really appreciate it if you would share with the rest of us here so that appropriate remedial steps could be taken.

 

It is strange how it happens only when the car is cold. If I start the car a few hours after the car was parked and turned off, I will not see the message. I do not remember seeing this message last winter, but I was not looking for it.

One person on the internet, not here, said it was due to the car's battery being almost depleted. The reason he thought that is only because he replaced the battery and has never saw the message again. But by replacing the battery, he reset everything in the car. I don't buy that because I have no problem starting it and my battery tester shows the correct voltage for both the battery and alternator. Above all, the car was in for service in October, and one of the things they check is the battery, which was good.

Another person thinks it is just a glitch in the car's computer. That sounds like a more plausible explanation.

I thought maybe, it is just the EPB system booting up after say a night of cold. I did do an experiment, usually I wait until the dasboard display is done doing its graphics and shows the 0MPH before I put it in gear. In my test, I did not wait and put the car in gear a split second after I started the car. I got the EPB message for longer with beeping. The same beeping you would get if you activated or deactivated the feature.

 

I thought maybe, it is just the EPB system booting up after say a night of cold. I did do an experiment, usually I wait until the dasboard display is done doing its graphics and shows the 0MPH before I put it in gear. In my test, I did not wait and put the car in gear a split second after I started the car. I got the EPB message for longer with beeping. The same beeping you would get if you activated or deactivated the feature.

That's the only scenario I got the message during- hurrying up to shift a split moment after starting. Bad habit to start with without any funky messages. Once I noticed the pattern I told myself I should wait a few seconds each time I get going, but once in a while I find myself just shifting and that EBP message usually pops up.

 

Same here! there was someone else that had the same issue and I believe the fix was a new battery. Which makes sense, I know ive ran my battery down a few times and have had to jump it

 

Yeah. I just don't want to immediately think it's the battery since it has never given me trouble. A good way to see how depleted your battery may be, is to start the car at night. Since I leave the headlights in "Auto", the car is turning over with the lights on. My headlight do dim a little, and I mean a little. If they dim a lot, then yeah, your battery needs attention.

What I am going to do is email the mechanic. He probably has seen this and heard about this many times as he is the dealership mechanic, not an independent person.

 

an easy way to test i guess is hooking up a maintainer to it when its cold, and starting it up to see if the same notification comes up.

 

I believe EPB represents Electronic/Electric Parking Brake.
Not Emergency Parking Brake.

I have never seen (I mean paid attention) to any alert informing me the brake is disengaged.
I am trying to figure out how the parking brake/interlock is tied to a battery level. Sure, if the battery is too low to disengage there could be a warning if the brake isn't going to BE applied. Is the shift interlock tied to the parking brake circuit though, traditionally shift interlock is related to the foot pedal position.
I know, I know... Toyota does everything differently and what I know about other cars don't always apply to Toyota.

 

I believe EPB represents Electronic/Electric Parking Brake.
Not Emergency Parking Brake.

I have never seen (I mean paid attention) to any alert informing me the brake is disengaged.
I am trying to figure out how the parking brake/interlock is tied to a battery level. Sure, if the battery is too low to disengage there could be a warning if the brake isn't going to BE applied. Is the shift interlock tied to the parking brake circuit though, traditionally shift interlock is related to the foot pedal position.
I know, I know... Toyota does everything differently and what I know about other cars don't always apply to Toyota.

Newer vehicles are sensitive to voltage. long story short, lots of sensors that are expecting x amount of voltage. When car batteries start going out, certain parts of the vehicle aren't getting the normal amount of power which means sensors aren't getting x voltage anymore and start freaking out.

 

It would be interesting that the 12V battery is the issue on an actuator that can be driven in and out with a simple 9V transistor radio battery .... whoops, my age is showing

 

Simplified example. Sensor gets 12v in. Sensor is connected to the actuator you speak of. Purpose of this sensor is to relay the position of the actuator to the module in charge of collecting that data and doing function X, Y, Z etc with it. So sensor is like cool, for Position A i will send a 3.5v signal to the Module, for Position B I will send 6.5v. Well as your battery goes out/electical wear and tear that sensor gets less than the expected voltage and ta da, produces a voltage signal that is not 3.5 or 6.5 and the module is just like "bro i don't know what you are saying" and thats where the random codes and messages happen. Sorry if i misspelled something, typing on the fly.

 

I would suspect that the actuator is a stepper motor. In service mode, the stepper motor is retracted and also sets up the zero point for the actuator. Then once out of service mode, the stepper motor stepped out enough steps in order to determine where the pads are then stops due to the increase in current to the stepper motor. The computer then steps the motor out a predetermined number if steps so it doesn't drag the brake pads. Each time the brakes are applied, the stepper motor learns how many steps it took to get to the pads. This is how the it "learns" where the pads are due to wearing of the pads.

We use stepper motors in a similar way on the kidney dialysis machines that I am a technical writer for and this method of their use is tried and true and very reliable. Now, does Toyota actually do what I described, I don't know, but it make sense in my mind.

 

Thats cool!! So its looking for values within an assigned range. So it'd be like the values it was receiving didn't make sense. This is what happens when the batteries start going out. I know some vehicles now require you to go in with a scan tool and tell the car there is a new battery in it. If you dont, the car will overcharge it like crazy during deceleration and kill the new battery. Its funny bc with new cars its sometimes easier for us to train a computer person to be a mechanic than it is to take a seasoned mechanic and teach them computer skills

 

FK Heath beat me to it.

I agree with your comments and yes, I was a user of the manual brake, mostly the hand brake with a front wheel drive because it made it a fun drive.

In that case, it was not an emergency brake though, I wasn't using it in an emergency. More like a "fun handle"


I like the flashback, good stuff. Regardless, when discussing a modern Toyota RAV4, EPB is literally Electric Parking Brake. If the system was not in fact electric, I couldn't care less if anybody called it an Emergency or Parking brake, both could be considered accurate.
A person can feel like the name should remain unchanged from the 70's and call it Emergency. It would be similar to a person referring to their truck as a car. It simple is not an Emergency brake and a truck is simply not a car.

 

Hello all

I hope everyone had a great holiday.

I started noticing that when I start my 2019 Rav4 XLE when the car is cold, that I will get the "EPB Shift Interlock Activated" message flash for a split second on the dashboard display. This is the same message I get if I activate/deactivate the automatic parking brake. I always do have it activated though. I tried to research this online, but found a lot of answers that I don't think are correct.

Has anyone else been experiencing this and do you think it is a problem or just a harmless nuisance? If it is a nuisance, it doesn't really bother me, I am just looking for what it is.

Thanks

I've created a thread in the past that details this message: [UPDATE: Root Cause Identified] "EPB Shift...

Basically it is harmless and seems to increase in frequency as your 12v battery under the hood begins to perform poorly keeping a steady voltage at ignition.

Had my local battery shop confirm this by hooking it up to their diagnostic system. Alternator was putting out solid numbers but the factory battery was never getting topped off even on longer trips. For 10 bucks they put in a loaner battery and kept my factory battery for 48 hours in their shop restoring the battery on their bench. While using their loaner battery and also once I got mine swapped back I no longer got this EPB message at ignition.

Mine has now returned again with the cold temps and I am on the lookout for a good deal on an AGM battery to replace the crappy Toyota factory battery.

The shop said this usually happens to car batteries when something in the car is vampiring current while the vehicle is off. It is most likely caused by the well known DCM issues in the 2020+ Rav4. I had the TSB done on mine long ago after getting stranded with a dead battery, but feel like it damaged my battery somehow.

I often hookup Techstream to download the latest DCM Firmware and currently have the latest version. Even with the latest firmware and no remote services active on mine I still get an occasional weaker turn over. Usually after not driving for a few days.

Again, the message seems harmless and can be ignored. The Electronic Parking Break system just seems sensitive to voltages. It's just a message that confirms the EPB shifter linked function is enabled.