The door seals are a great thought, Casper, thanks! The foam ones are similar material and adhesive to what I used in testing (Nissan foam wiring insulators), meant to reject water and weather.
With respect to those buttons, they're all pretty much the same thing from all OEM's. Ultrasonic transceivers, mostly in the 40KHz range. They send out an ultrasonic "ping", and the time from transmission to echo tells how far away the object is. If your neighbor's dog goes nuts every time you shift to "R" in your driveway, now you know why. The most modern ones also have "phased array" characteristics that let a processor decide the general direction of a returning echo, I suspect that sort is being used in Nissan's RAB corner sensors.
Rear Auto Brake and rear sonar with bike rack
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VStar650CL
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Re: Rear Auto Brake and rear sonar with bike rack
Anyone know if there was a final resolution to the issue?
I'm picking up a 2021 SL tomorrow and am hoping I don't have the same issue. Don't really want to be taping up the sensors...
I spoke with the dealer and he said I may have an issue with the lift gate sensor (foot wave) but that the sensor locations have been changed ~ maybe not under the center of the bumper.
Also, so far I can't find a trailer hitch for the 2021. Curt say they have it engineered (model number 13471) but it's not in production yet - available early next year. Supposedly none available from Nissan.
I'm picking up a 2021 SL tomorrow and am hoping I don't have the same issue. Don't really want to be taping up the sensors...
I spoke with the dealer and he said I may have an issue with the lift gate sensor (foot wave) but that the sensor locations have been changed ~ maybe not under the center of the bumper.
Also, so far I can't find a trailer hitch for the 2021. Curt say they have it engineered (model number 13471) but it's not in production yet - available early next year. Supposedly none available from Nissan.
Last edited by Rogue One on Tue Dec 15, 2020 5:34 pm, edited 1 time in total.
Reason: TYPO
Reason: TYPO
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VStar650CL
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Re: Rear Auto Brake and rear sonar with bike rack
The 2021 is a complete redesign and may not have the issue. I'd check the sensor locations, though. If your rack will be anyplace within about 60 degrees of angle from the centers of the sensors, the sensor will most likely "see" it and you'll probably end up foaming them. Please do let us know, I haven't seen a '21 with a rack yet in the dealership.
Re: Rear Auto Brake and rear sonar with bike rack
Thanks, Will do!
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VStar650CL
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Re: Rear Auto Brake and rear sonar with bike rack
Update: The '21's have sensors that are much higher on the bumper, with the outer ones used by RAB angled slightly outboard to avoid "looking directly" at a trailer or rack. It's a much better setup and we now have a trailering customer who says it works fine. It should also work fine with an empty bike rack, but possibly not a loaded one depending on the arrangement of the bikes.VStar650CL wrote: ↑Tue Dec 15, 2020 4:51 pmThe 2021 is a complete redesign and may not have the issue. I'd check the sensor locations, though. If your rack will be anyplace within about 60 degrees of angle from the centers of the sensors, the sensor will most likely "see" it and you'll probably end up foaming them. Please do let us know, I haven't seen a '21 with a rack yet in the dealership.
Re: Rear Auto Brake and rear sonar with bike rack
Sorry it took me forever to test this out but I put foam over all 4 sensors and it didn’t change anything. I was surprised. I used self adhesive 3/16” thick foam.VStar650CL wrote: ↑Tue Dec 01, 2020 10:06 amSoooo.... I'm waiting with bated breath, how did it work for you?
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VStar650CL
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Re: Rear Auto Brake and rear sonar with bike rack
It should only be the outboard ones that need it, the inboards aren't used by RAB. Maybe it's the type of foam you used? Or maybe the position and construction of the bike rack differs from what I tested against, I used a sheet metal panel held by hand and maybe that wasn't a fair approximation. The foam I used was closed cell. If that isn't it, I'd suggest trying some foam or cloth on the surfaces of the rack that are in the sensors' view to reduce the reflected signal. The test made clear that blinding the sensors will work, it's just a matter of finding the right materials and places in order to blind them.
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VStar650CL
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Re: Rear Auto Brake and rear sonar with bike rack
Now that I think about it, the surest option might be to remove the sensors and plug them back in behind the bumper with a very thick block of foam stuck in front. The sensors aren't difficult to take loose, they're only held in by pawls.
Re: Rear Auto Brake and rear sonar with bike rack
Wow, what the hell. I just bought a 2019 rogue with specific plans of putting a bike rack on it.
Posting to sub.
Posting to sub.
Re: Rear Auto Brake and rear sonar with bike rack
Did you ever try anything else to fix this issue?alefak wrote: ↑Sun Jan 24, 2021 1:21 pmSorry it took me forever to test this out but I put foam over all 4 sensors and it didn’t change anything. I was surprised. I used self adhesive 3/16” thick foam.VStar650CL wrote: ↑Tue Dec 01, 2020 10:06 am
Soooo.... I'm waiting with bated breath, how did it work for you?
I just bought a bike rack, and yea, pretty much the same issue. REB makes a god awful noise. I think it's actually possibly dangerous. For example, if I need to reverse a small amount like during a 3 point turn or something.
@vVStar650CL did the Nissan Engineers ever get back to you?
Re: Rear Auto Brake and rear sonar with bike rack
No. Resigned to turning the brake off in the dash settings each time.Bored2001 wrote: ↑Sat Apr 10, 2021 10:18 pmDid you ever try anything else to fix this issue?
I just bought a bike rack, and yea, pretty much the same issue. REB makes a god awful noise. I think it's actually possibly dangerous. For example, if I need to reverse a small amount like during a 3 point turn or something.
@vVStar650CL did the Nissan Engineers ever get back to you?
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VStar650CL
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Re: Rear Auto Brake and rear sonar with bike rack
No engineers but the DTS did, I just got distracted and forgot about posting it. Turns out the outboard sensors are more powerful on cars with RAB than without, so it takes a lot more foam to blind them. The car I initially tested on didn't have RAB, just normal rear sonar. However, there is a not-too-difficult way to blind the RAB sensors, which is to pop them loose and pull them inside the bumper, then point them at the body of the car buried in a foam block. By putting a hard target (the car body) an inch away, the reflection is too fast for the sensor's "detection envelope" and the sensor can't translate it. The outboard sensors aren't difficult to remove, the corners of the bumper cover are open-access and the sensors are held in by only two pawls on a mounting sleeve. The only tool required is a small hook to relieve the pawls.
Re: Rear Auto Brake and rear sonar with bike rack
If i'm reading this right, you just need to reflect the signal within 1 inch of the sensor to 'blind it'. You think a thin sheet of metal just placed over the sensors would work? Something applied with double sticky tape or something, so as to be relatively removable as I don't plan on running my bike rack 100% of the time.VStar650CL wrote: ↑Sun Apr 11, 2021 4:59 amNo engineers but the DTS did, I just got distracted and forgot about posting it. Turns out the outboard sensors are more powerful on cars with RAB than without, so it takes a lot more foam to blind them. The car I initially tested on didn't have RAB, just normal rear sonar. However, there is a not-too-difficult way to blind the RAB sensors, which is to pop them loose and pull them inside the bumper, then point them at the body of the car buried in a foam block. By putting a hard target (the car body) an inch away, the reflection is too fast for the sensor's "detection envelope" and the sensor can't translate it. The outboard sensors aren't difficult to remove, the corners of the bumper cover are open-access and the sensors are held in by only two pawls on a mounting sleeve. The only tool required is a small hook to relieve the pawls.
I notice that both me and OP have hitch mounted tray style racks. Think this'll be an issue with a hanging style hitch mounted rack?
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VStar650CL
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Re: Rear Auto Brake and rear sonar with bike rack
Might work as long as the foam is thick enough that it won't let the metal act as a tympanum and just transfer the sound energy. I'd say it's worth some experimentation.Bored2001 wrote: ↑Mon Apr 12, 2021 1:22 pmIf i'm reading this right, you just need to reflect the signal within 1 inch of the sensor to 'blind it'. You think a thin sheet of metal just placed over the sensors would work? Something applied with double sticky tape or something, so as to be relatively removable as I don't plan on running my bike rack 100% of the time.
Maybe not, depends if the bikes are still in view of the outboard sensors at an angle they can "see". If it's mounted high enough or tucked in very close to the tailgate, then the sensors may not detect it.
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travis2021
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Re: Rear Auto Brake and rear sonar with bike rack
I can confirm the same thing happens with my 2021 Leaf with a hitch rack. It screams bloody murder and slams on the brakes. I'm going to try and see if Leaf Spy can set auto brake to always be off, but I'm not holding my breath.
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VStar650CL
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Re: Rear Auto Brake and rear sonar with bike rack
The only thing I've found that works is to pop the outboard sensors out of the holes and bury them in thick foam behind the bumper cover. The RAB transmitters are simply too powerful for any sort of external covering to work, and none of the RAB systems seem to have an easy turn-off method or a way to change the default to "off". Sometimes these engineers only get an A+ for irritation, and this is definitely one of those instances.
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