2016 BSM NOT WORKING

Hello Tacoma Peeps.

I have a 2016 trd sport access cab, The BSM switch is not powering on when switch on. No error msgs, no door mirror indicators. The sensors on the rear bumper seems to be working fine since park assist works fine. All fuses check out to be ok. What can the issue be.

 

BSM and park assist use different sensors, so I wouldn't rule them out.

 

Park assist and BSM are different sensors.

 

Access cab doesnt have sensors in the rear bumpers

 

Ok, didn't know that. Any schematic of the system.

 

See if you have the little engraved car in the outside part of the mirror.

 

Yes I have that, but it is not lighting up

 

Has it ever worked?

 

We have had some issues with water infiltration.
Need to get it in and have the system scanned

 

FSM BSM troubleshooting for inop system (Switch will not light up when pressed, no error msg) is to check for voltage at the rear harness connector and then at the BSM connector. I had same issue when buying used, dealer troubleshoot found failed right side BSM sensor. Replaced both sensors at a cost of $2800 parts & labor! Not sure what sensors cost, it's not a difficult DIY job for install but there is significant labor in the adjustment and calibration after install. If you repair it, pack those rear harness and BSM connectors with dielectric grease before connecting. They get blasted with water constantly when it's wet/raining.

Ill try and post the troubleshooting steps if I can find them...

Edit: see attached Pg 6-7. Basically, if you dont have voltage at Connector BE1 Pin 4 then chase that wire forward until you find where you do have voltage. Repair/replace harness as necessary or the BSM switch/relay. If you do have voltage at BE1 Pin 4, then check for voltage at the BSM connectors B12/B13 Pin 5. if no voltage there, repair/replace rear harness. If voltage there, replace the BSM sensor(s). You could also work "backwards" and start at the BSM sensor connectors but they require that the bumper cover be removed to access as far as I can tell. They are buried pretty well and access from under the truck is limited.

 

The last user said it worked fine. I will try to scanned it with techstream.

Chet

 

I had a sensor replaced under warranty a couple years back and I remember one sensor alone was somewhere around $850. If memory serves me correctly.

 

That is crazy, I dont really need it. I just wanted it to wrk. I am waiting a copy of my techstream software to tried to diagnose it. I am hoping it is just a bad switch.

 

Access cab do have sensors in the rear bumper

 

Access cab do have sensors mounted in the rear bumber

 

Thank you for the TSB and the tips. How do I access the rear bsm connector. Do I have to remove the rear bumper ends. Are the park assist sensors and the bsm sensors the same. On my truck the park assist works fine my rear bumper has 4 sensors. Thank you

 

send a pic. I've never seen it before

 

Well I'll be damned.

 

There is an active TSB on this had both my sensors replaced on it after the BSM stopped working. Yours is probably out of warranty so I would just ignore it since as it’s been pointed out those sensors are quite expensive.