Parking sensor calibration w/ aftermarket bumper

Hello!

I'm curious what folk's experience with parking sensor re-calibration after a lift/front bumper install has been for a 3rd Gen Tundra?

I recently purchased a CBI Baja steel front bumper and 3" lift installed by a reputable shop. Afterwards, I had the parking sensors calibrated by my dealership. After the calibration, I noticed the front sensors didn't trigger when I was approaching something close by. I have a tight entrance to my parking garage, which would constantly trigger the parking sensors before the upgrades and calibration, but regardless of how close I'd get they wouldn't go off. However, they would go off randomly while at a stop light/stop sight as cars were passing by.

I took it back to the dealer, but they said there's nothing they can do and that the aftermarket bumper is the root cause and also not guaranteed to work properly with OEM equipment. CBI bumpers are pretty common, and I'm hoping there may be a solution to get these working as expected. Right now, my only recourse is to disable the parking sensors, which do come in handy with such a large truck.

 

My c4 randomly beeps at stop signs with dips in the road or slowly entering driveways, but they still work just fine!

 

How often does it beep for you? Mine is literally almost non stop at any stop sign or stop light

 

Only at spots with a dip thankfully. Mine was bad and I retaped them in place and it fixed it

 

1794ever had a similar issue, and it ended up being miscalibrated by the dealer. Had a CBI bumper as well. He finally got them to fix it.

 

What do you mean by retape?

 

Thread bump - I’m experiencing a similar problem after I replaced the lower plastic subframe after an oopsie this winter and installed a Scorpion bumper. The parking sensor angles aren’t quite the same as before.

The sensors are basically taped to the subframe with double sided tape. There are calibration marks on the subframe to help align the sensors but they’re very sensitive to angle changes. They will squawk if things aren’t just right.

I found a video where a mechanic calibrated the front sensors on a Sienna using his Autel, a 11mm socket and angle gauge to measure the sensors - neat trick and I may try the same before I succumb to the dealer.

 

My front bumper was repaired after hitting a deer and the auto body shop but the sensors in upside down since these are the first sensors that Toyota has made for trucks that are actually directional up or down. They would squeak at stop lights and such. So it could be something like the previous post said in terms of their alignment.

 

They’re installed correctly - I was super careful with the wiring harness when I replaced the subframe and took pictures as I went along. But between the new subframe and necessary tweaks as I installed the new bumper the angles are just off a bit. I’m pretty sure a calibration will do the trick and I’ll update the thread after that’s happened.

 

I am interested in finding if there is a method of calibrating the sensors yourself, or if there is an aftermarket solution. I have been to the dealership twice now for parking sensor system malfunctions. So far the dealership has covered everything under warranty, although it hasn't been an easy process at all.

 

The right way to do it involves Techstream and some expensive calibration equipment. There are some “unsavory” versions of Techstream out in the wild but I don’t trust them - YRMV

However I can verify that some Autel bidirectional scanners can register new parking sensors and calibrate the sensor angle. I was using a MK808S with Autel Toyota software version 5.20 and was able to access the calibration menu. I didn’t go “all the way” as I have a little cleanup and one more R/R of the bumper fascia before I’m ready to set the sensors. But the system behaved as expected with the proper flashing light and “See your Dealer” message on the dash while I was in the ECU.

Autel Scanner function table is here if you want to check for the function:
https://autel.com/us/vehicle-coverage/

Sorry no pics or progress report yet but I was thwarted by a thunderstorm. Hence I’m posting here

If you park the truck on a level surface, calibrate an angle sensor to 0 degrees and affix the proper socket (11mm) to the parking sensor as a gauge you should be able to get an angle reading sufficiently accurate to reset the parking sensor angles and get rid of the low speed squawk. At least that’s the theory - I’ll update as the saga continues

 

This helped me out tremendously when I installed the CBI bumper on my 3rd Gen. After following this, I was able to adjust my sensors and prevent any false readings when I hit a dip or coming up my steep driveway.

It shows the angle the sensors need to be at, and the angle range tolerances you need to be within for each of the 4 positions.

 

Bump

One can calibrate the sensors as described earlier but the angles are not the same as the Prius - minimum angle is 0 up to about 12 degrees.

Something else to bear in mind is that while the sensors don’t have a specific up/down orientation, the retainers do. The clips are also very fragile. AMHIK. They are not intuitively designed as there is no orientation arrow and the print on the back of the clip will be upside down when correctly installed. They also have adhesive which is only good for one mistake-again AMHIK

Hope this helps anyone else who has similar adventures with the sensors and subframe !

 

Thanks, I will make a note of this when upgrading the bumper on my TRD Pro

 

Thanks, is some kind of Techstream is also needed for the same?
2023 TRD Pro

 

You can use Techstream or some bidirectional scanners have the functionality. I have the Autel MK808S and it recognized the ECU and could program the angles.

 

how sensible are these sensors? I'd imagine very little change would happen with bumpers like the covert or similar but seems like a lot of folks have issues... I'm in the process of figuring out a new bumper and this seems really annoying

 

It's not that bad if you (and/or the bumper manufacturer) get the fitment right. Mine was a tough case because I had to replace the plastic subframe while I was in there. If you're just cutting the subframe and not relocating sensors you're less likely to have problems.

Buy a cheap angle gauge, measure your sensor angles before and after. There's at least a couple degrees play when you button everything back together. If you need a calibration, hey, its just