Collision light problems

My collision warning light keeps cycling on and off, never get a warning message and have thrown no codes, any ideas as to whats going on? 2019 Tacoma 2 wd

 

You mean this light?

Do you have any lift or aftermarket bumper? Usually that means the PCS has a fault and the sensor most likely needs cleaned.

 

Just purchased this, yes that's the light and it does have an after market bumper, isn't the sensor behind the grill logo? it looks like it was rube-goldberg attached and it seems that the bracket to hold it is missing.

 

Post pictures so we can see what you’re working with. Sensor behind the grille, whatever is rube goldberged, any suspect wiring that looks out of place, bumper… ect

 

Depends what grille you have. Some are below the emblem at the bottom of the grille and some are incorporated with the emblem. A bumper with any type of hoop or bar has the potential to interfere.

 

OP -
You've already found your problem. Good job.

The PCS (pre-collision system) sensor is almost undoubtedly your issue here. The challenge now is to mount it correctly and perhaps get it re-calibrated with respect to the angle it is pointing at the roadway, height above ground, etc....

This is a very sensitive device. I had to have mine re-calibrated when I put a 3" lift on my Taco. You will need to find a shop that pays for access to Toyota's TechStream software. Because IIRC, that software is the only way to recalibrate the sensor. It's actually a pretty intricate procedure that I believe involves reflectors and/or mirrors and whatnot to get it set correctly.

Anyway, like you, I knew exactly what my issue was. So it was just a matter of calling around and finding a shop with the software and knew what I was talking about and had done it before. And since I was very specific, as in "please proceed directly to the PCS sensor re-calibration" - no other troubleshooting required - I was able to get it done for ~$200. Something like 1.25 hrs of shop labor and a TechStream service fee plus taxes.

I'm certain it would have been much more than that at the dealership. HTH!
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For those wondering,

"Reuben Garrett Lucius Goldberg, better known as Rube Goldberg, was an American cartoonist, sculptor, author, engineer, and inventor. Goldberg is best known for his popular cartoons depicting complicated gadgets performing simple tasks in indirect, convoluted ways."

LOL - I bet there are countless mechanics out there who would say the same thing about Toyota's engineers even though they happen to be very very very very very good overall.

 

Thanks, that must be it - it is mounted with zip ties and is unstable, which is why it is cycling on and off. Good advice on shopping around - Dealers are a huge rip-off