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Thanks, I was pretty sure of that, but I still don't understand why the one abrupt stop backing up and then it never happened again, nor do I understand how the RAB got turned off. I did not do it, but it was off when I went to shut it off, yet the RAB must have been active to stop me so abruptly that one time.
I've yet been able to consistently replicate any action when towing. Glad I'm not the only one, lol!!! :ROFLMAO:

(no, seriously, joking aside, I was hoping one of you would figure out the pattern or criteria)
 

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Was any consistent pattern ever found for this? I towed with the Ascent for the first time today and while sometimes it was off or stayed off after manually setting it other times it seemed like it just randomly came back on and stopped me.
 

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Bumping this 7 months later 😄

I was towing again and still have to occasionally fight with RAB kicking in. Has anyone had any luck figuring out a way to consistently keep it off?
 

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Let it happen once then it’s disabled for the duration of the trip?
 

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Discussion Starter #45
That is a bit hard to do when you are parking a trailer and going in both forward and reverse. For, me, the RAB turns on when I move forward and then I cannot get it back off again. :-(
 

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That is a bit hard to do when you are parking a trailer and going in both forward and reverse. For, me, the RAB turns on when I move forward and then I cannot get it back off again. :-(
Last couple times I’ve towed I backed up and let RAB activate. I’m pretty sure I was already on the brakes lightly at the time so I gave it a little gas after the RAB and then all the RAB OFF icons came on and stayed that way the whole time the engine was running.
Have you tried that or did you manually disable it from the touchscreen?
 

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Manually disabled from touch screen lower left corner.
While its a rather annoying way of doing it, it does seems to stay off after you override RAB actually engaging. Its loud when it engages obviously so you're likely to turn a couple heads, but after the first time its off!
 

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Mine is still spotty, 8 times out of 10 it shuts itself off after shifting to reverse with my camper attached. But a couple times I got the "oh crap" braking from the computer.
 

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Manually disabled from touch screen lower left corner.
Yes, this is the proper way to do it but it sure is annoying because you have to press and hold two onscreen buttons before it will disable the RAB and warnings. Under pressure, it seems to take forever. When I'm in line at a crowded boat ramp on a hot day and it's my turn to back my boat trailer into the water, I can just imagine what the others in line are thinking: Why is that guy not backing up and playing around with his infotainment system? I've even been subject to a few horn blasts to get going.
 

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Discussion Starter #51
Two buttons, which ones are you holding at the same time? I've never pressed two at the same time.
 

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I can just imagine what the others in line are thinking: Why is that guy not backing up and playing around with his infotainment system? I've even been subject to a few horn blasts to get going.
I launch at a private ramp which is monitored at peak times. It's 2 lanes. If you cross the line or have to pull forward to make an adjustment you have to go back to the end of the line. Yup. I can just see it now. "My RAB stopped me I'm waiting for it to disengage". ☹

I'd really like to see an ability to create our own "macros" with an icon right on the home screen. I'd have one for trailer maneuvering and one for highway trailering.
 

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I launch at a private ramp which is monitored at peak times. It's 2 lanes. If you cross the line or have to pull forward to make an adjustment you have to go back to the end of the line. Yup. I can just see it now. "My RAB stopped me I'm waiting for it to disengage". ☹

I'd really like to see an ability to create our own "macros" with an icon right on the home screen. I'd have one for trailer maneuvering and one for highway trailering.
Right, boat ramps can be intense, everyone waiting in line for their turn losing patience and watching closely at every move you make. Certainly no time to be playing around with some poorly designed onscreen dash buttons each with a ridiculous built-in delay. Whoever came up with that never launched a boat at a busy boat ramp. 🤬
 

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I stand by my previous statement. Just let RAB do it’s thing once then it’ll disable itself. The noise is less embarrassing if you meant to do it
 

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Hello, first time posting here, but I'm actually trying to create a definitive guide on what conditions must be set for RAB-auto-disable (I'm NOT affiliated with anyone, just doing this for fun in my driveway). RAB stays on for the first 5 seconds or so when reversing with my utility trailer, but then it deactivates as I'm backing up, with no RAB brake applications during that time. 2020 Ascent Touring.

So I'm really curious, what kinds of loads is everyone pulling when RAB engages while reversing? how close to the tow vehicle is the body of your trailer? (better phrased: how close is something RAB sensors can actually see, given your tow ball probably isn't triggering RAB...) what kinds of tongue weights? backing uphill? downhill? I'm looking to create a "worst-case-scenario" where RAB is coming on when I'm backing up with a trailer so that I can experiment from there, and hopefully pass on my findings. Thanks!
 

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Discussion Starter #58
It happens to me when I am backing up quite and incline in my drive, stops the car at a point where he car will not move backward at all, no matter how much I press on the accelerator and the engine is racing and then I have to pull forward, RAB disengages and I have to try again and RAB won't go off by holding the virtual button, then it is rinse and repeat, over and over, finally, after many, many tries I can "push", backing up, the trailer up the incline, but it is a very, very frustrating process.
 

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I just pulled a 5000lb low boy (4 pin / automatic hydraulic brakes - didn't use my controller) around for 500 miles yesterday, tons of stops, starts, backing up, loading, unloading, manuevering and relocations. Pushed the BSD/RCTA once in the morning to turn if off (pursuant to my manual) and didn't have a single issue the entire day with RAB. Pushed the button again after returning the trailer and RAB kicked in when I was backing into the gas pump stall. :unsure: There must be something that others are doing that I'm not to cause that issue.
 

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Alrighty,
I'm uploading a video to youtube that documents all of my testing and my little DIY fixes, but Ill go ahead and summarize here:

the RAB system is able to tell if there is a bulky object (a.k.a trailer) right behind the center of the vehicle, but it's not very good at it, and needs some help. if you have a trailer with a lot of bulky stuff on the tongue (like a motorized jack or propane tanks) the Ascent will "see" it and disable RAB. same goes for a lot of the chunkier Bike racks out there. if you have something small or thin hooked up to the ascent, or you're using a hitch with a big drop, the RAB sensors won't "see" it right behind the vehicle, only the body of the trailer further back, which RAB will then treat like an obstacle and will intervene.
this explains why RVers and other "bulky trailer" towing folks haven't had this issue, whereas anyone pulling a boat trailer or a utility trailer probably has.
Supposedly, if the vehicle sags (detects a "change in ground clearance", per the owners manual) enough due to load, It will auto-disable RAB for that reason alone, but not everyone is pulls a 4,990-lb trailer with a 499-lb tongue weight, so this information isnt practical as far as disabling RAB by default for Everyone's trailering needs...

now for solutions:
step 1. go into your i/Set menu in the gauge cluster with the ascent in PARK. page 5/9 is for RAB settings, go down to disable the sonar beeping noise thing. exit.
step 2. you've got options:
-if you slap some cardboard on the tongue of your trailer or on your hitch itself, (provided the piece is big enough) RAB will pick it up, and auto-disable. you can do this just to your hitch even without a trailer connected with minimal tongue weight. I cut out a 12x18" piece of Coroplast and zip-tied it to my dropper hitch. works like a charm. makes the most sense to me if you have more than one trailer, even if you also need to do this mod to multiple hitches.
-if you're really desperate, or just hate RAB in its entirety, you can tape over the RAB sensors on the bumper, leaving a little bit of air gap between the tape and each sensor, and RAB will think it is mud or snow and auto-disable, as its stated in the owners manual. Woo, duct tape on a $35-45k car...
-if you are looking to add any accessories to your trailer (spare tire carrier, electric jack, propane, battery, toolbox, etc...) consider SAFELY adding that item really close to the front of your trailer (based on my testing it should be no further than 17" away from the bumper of your ascent to be considered a "trailer" by the RAB system) if you only have one trailer, this probably makes the most sense.



I would suspect if there's any sort of mid-cycle refresh coming, they're going to toss in that 12 inch screen, which, for all of its flaws, does have the option to permanently disable RAB in the Outback/Legacy, but idk if that would also require an updated BCM or ABS module.

looking forward to the community improving on my methods and conclusions so we can all learn something!
 
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