Warning lights: Multi-terrain Seleft and Four-wheel Indicator lights flashing

To my friends and 4Runnertiers!

I have a 2016 4Runner Trail Premium and have been going nuts looking up and down this (and other forums), mechanics manuals, and I may have finished the web at this point.

I come to you with humility and a sense of pride that someone on here may have an answer or various answers I can test out.

The Multi-terrain Select Indicator and Four-wheel drive indicator lights are flashing. The first slower than the second, but both flashing.


Here's what I've tried so far:

• Put the 4wd mode selector to 4Lo. Drove in Reverse for 100+ ft. Also drove forward for 100+ ft Did the same for 4Hi. Tried this a few times over. No luck.
• Checked the fuses, both in the car cabin and in the engine bay.
• Scanned and cleared any and all codes a few times using a BlueDriver Bluetooth OBD2 scan tool.

A few questions:

1. Could it be a relay? If so, which one?
2. One of the wires loose on the ABS or other sensors?
3. Traction control messed up?
4. Any relation to a parking brake bypass switch I've added to my aftermarket stereo (Pioneer AVIC8200-NEX)? I've had the switch for a while, but fiddled around with the radio and wondering if there's any causation.
5. Related to the Pedal Commander I use?

Many thanks in advanced!

Rob

 

What codes are you getting?

Clearing the code is not fixing the problem.

 

Its a speed sensor, most people have had this issue. They are a weak point and allow lots of build up of dirt damaging a sensor. It is usually the ABS speed sensor. Mine was the one on my transfer case.

 

This would be my bet... I had the exact same issue you had OP, and it was a wheel speed sensor. I had no 4x4/traction control/crawl controls and then a snow storm hit... The Toyota tech said they are very weak and break pretty much by doing any suspension work and dirt.

 

Funny part was that I didn't get any codes.

 

Thanks! Wonder if I touched it when I added the CBI front and rear skid plates a few weeks ago, even though the warning lights didn't come on until recently. I have the skid plates off now (to add protective coating), and can probably see better.

Ir assume there multiple speed and/or ABS sensors? Can you tell through a visual inspection if they're not working or would I need to do a voltameter or something?

 

Found these instructions to test the ABS Speed sensor(s).
https://www.2carpros.com/articles/abs-wheel-speed-sensor-test

 

Also, if they do end up being the ABS Speed sensor, then think something like the SDHQ guards would help?
https://trail4runner.com/2019/02/06/sdhq-abs-speed-sensor-guards/

 

I have those on. Just in case I say. Just a little added security I guess.

 

Neither did I...but the dealership did some other test and diagnosed it very quickly.

 

Just dropped it off to the dealership in Sunnyvale, CA. I've had them work on stuff before, so let's see how it goes. Good time for that airbag recall too

 

Dealer chased down the wiring and signals and found some of the wires for the front differential actuator cut somehow. Wtf?!?!? They're going to solder and reconnect them again and check again.

 

Wow!! Where is that located?

 

That's the view looking from the rear passenger side, near the transmission oil pan.

 

Do you think rats or mice could have done that?

 

Honestly, not sure. I'd assume rodents would prefer the engine bay where it's warmer, but who knows?!?!

I'm wondering if any of the steel skid plates I added would have nipped it during install or if I hit something while driving. The wires face forward, which make it susceptible to being damaged by oncoming objects, much like how the ABS Speed Sensors wires are vulnerable.

Dealer is estimating 3 hours of labor (@ $200/hr!!!) to solder the wires, adding some additional length to give it a bit more slack in case the wires caught on something.

I can't wait for my skid plates to be done from the powderc shop. I'll be picking up the SDHQ ABS sensor guards too.

 

Well it doesn't look clean cut so I think either something hit it and cut or was rats.

 

Circling back with the group. I'm $600 lighter in the wallet, but the problem seems to be fixed. Here's a summary from the dealer...