Trac light on after alignment, code C120A?

[Canazes9]

Sounds awfully close to the problem we initially thought we had...to the best of my understanding the last step of the ZPC that was needed to be performed was to initialize the master cylinder solenoid by making it aware of your DAC control option. Basically, so it knows to operate the ABS to do all the nifty brake pedal modulating and good stuff when you're using ATRAC and DAC.

But hey, a few bucks for some extra peace of mind is just fine in my book. Heck, I'm just glad you finally got that straightened out, and glad that it didn't end up to be anything serious

And it may be the exact same thing - hoping someone that "speaks Toyota" can tell me. I tried several more times yesterday to perform zero point calibration and could not ever get DAC light to come on. I noticed that when you turned on the ignition the DAC light wasn't even lighting in the indicator function check. I asked the service writer if they reflashed the computer - "don't know".

I've been thinking about it a lot. Prior to this, when the lift was installed, one of my abs sensor wires was broken. I had a bunch of lights, we figured it out and replaced the wires. When the wires were replaced the lights went out. The alignment had already been performed and it didn't get plugged back into the computer.

When this alignment was performed, and the 4R was plugged into the computer, it was reading a bunch of old codes from the broken wire (even though we're no lights on in the dash). I wonder if those old codes that seemingly didn't get cleared caused the problem? I brought it back to my buddy where the alignment was performed. He made a copy of the invoice and was going to talk to Hunter (alignment machine/computer manufacturer) and see if they had any ideas.

David

 

[eddiebx]

And it may be the exact same thing - hoping someone that "speaks Toyota" can tell me. I tried several more times yesterday to perform zero point calibration and could not ever get DAC light to come on. I noticed that when you turned on the ignition the DAC light wasn't even lighting in the indicator function check. I asked the service writer if they reflashed the computer - "don't know".
David

It's probably slightly different for you and me, but on mine when I do that final step (with the ignition in "ON" and the jumper across the two pins), every time I press and hold the crawl control button, the little crawl control light on the dash turns on and off with it. Do you mean that you don't see that light go on and off when you're pressing the DAC button?

Kind of sucks that the service writer has no clue considering that he's the one writing the uhhhh service, lol...any chance you could speak to the tech that was assigned to your truck?

I understand what you mean, it would bother me too to not know whats up

Maybe if [MENTION=66389]BlackWorksInc[/MENTION] could chime in here, or perhaps shoot him a PM? He's a pretty knowledgeable toyota dealer tech so he might be able to decrypt the code on your invoice and put an end to this.

 

[Canazes9]

It's probably slightly different for you and me, but on mine when I do that final step (with the ignition in "ON" and the jumper across the two pins), every time I press and hold the crawl control button, the little crawl control light on the dash turns on and off with it. Do you mean that you don't see that light go on and off when you're pressing the DAC button?

Correct, I could not get the DAC to light in that final step with the ignition on and the jumper across the pins. I could not engage DAC in 4Lo (or ATRAC). Additionally, when I wasn't doing the zero point cal, but just turning the ignition on starter not engaged, the DAC would not light as part of the warning light check. Now that it was serviced and they did whatever they did, the DAC engages in 4lo and the light illuminates as part of the gauge cluster light check.

I would love to hear what [MENTION=66389]BlackWorksInc[/MENTION] thinks about it if he is available to give some input!

David

 

[BlackWorksInc]

7777 Sounds like an internal operation code for the dealership, its probably specific to their setup as its not something I have ever seen.

It could be possible your uncleared DTCs from the broken wire were preventing the system from properly learning the new values. Typically the TIS TechStream 1.0/2.0 wants you to have the codes clear prior to doing calibrations otherwise it may not set right.

I honestly could not tell you what was the issue since I wasn't involved with the vehicle, but it could be that in this particular case using the Scantool versus trying to do it the "manual" was what needed to be done. I've had a vehicle where the factory communication lines were damaged and so the factory tool wouldn't communicate with the system, but a generic OBDII scantool had no problem since it uses different lines and we were able to diagnose and repair that vehicle. I've also had a vehicle where a coworker kept trying to do the "manual" method for a relearning procedure, after many failed attempts we threw the scantool on it and it worked fine. So... yeah, modern cars can be weird sometimes. :/

 

[Canazes9]

7777 Sounds like an internal operation code for the dealership, its probably specific to their setup as its not something I have ever seen.

It could be possible your uncleared DTCs from the broken wire were preventing the system from properly learning the new values. Typically the TIS TechStream 1.0/2.0 wants you to have the codes clear prior to doing calibrations otherwise it may not set right.

I honestly could not tell you what was the issue since I wasn't involved with the vehicle, but it could be that in this particular case using the Scantool versus trying to do it the "manual" was what needed to be done. I've had a vehicle where the factory communication lines were damaged and so the factory tool wouldn't communicate with the system, but a generic OBDII scantool had no problem since it uses different lines and we were able to diagnose and repair that vehicle. I've also had a vehicle where a coworker kept trying to do the "manual" method for a relearning procedure, after many failed attempts we threw the scantool on it and it worked fine. So... yeah, modern cars can be weird sometimes. :/

Thanks for your input!

David

 

[eddiebx]

Correct, I could not get the DAC to light in that final step with the ignition on and the jumper across the pins. I could not engage DAC in 4Lo (or ATRAC). Additionally, when I wasn't doing the zero point cal, but just turning the ignition on starter not engaged, the DAC would not light as part of the warning light check. Now that it was serviced and they did whatever they did, the DAC engages in 4lo and the light illuminates as part of the gauge cluster light check.

I would love to hear what [MENTION=66389]BlackWorksInc[/MENTION] thinks about it if he is available to give some input!

David

So I had a few moments earlier and tested this out for you...I cleared the zero point data, and did all the steps to recalibrate the zero point data, up until it was time for initializing the crawl control and stopped before doing that step.

I found that it also did exactly what you were describing (when you turn the ignition to "ON" and the dash lights do it's pre-start check thang...the crawl control indicator does not light up at all throughout the sequence).

Once I finished the final steps and checked the pre-start dash indicator light show, the crawl control indicator lit up again. So I guess what you experienced before was somewhat normal, in that the DAC indicator is not going to come on if the C120A DTC is present.

Sorry that was not exactly much help, but hopefully eases your mind a little bit, lol.

 

[Canazes9]

So I had a few moments earlier and tested this out for you...I cleared the zero point data, and did all the steps to recalibrate the zero point data, up until it was time for initializing the crawl control and stopped before doing that step.

I found that it also did exactly what you were describing (when you turn the ignition to "ON" and the dash lights do it's pre-start check thang...the crawl control indicator does not light up at all throughout the sequence).

Once I finished the final steps and checked the pre-start dash indicator light show, the crawl control indicator lit up again. So I guess what you experienced before was somewhat normal, in that the DAC indicator is not going to come on if the C120A DTC is present.

Sorry that was not exactly much help, but hopefully eases your mind a little bit, lol.

Eddie,

Thanks!

David

 

[Scott@Hightech]

Glad it was something simple

 

[Asugm13]

Ok, I need some help. Had the tires rotated during a routine oil change today, the tech noticed a little uneven wear so they checked the alignment. Alignment was off, they aligned, now the Trac light is on and it's getting the error code C120A and it won't clear.

This is a 2013 SR5 4wd. Lifted w/ icon coil overs up front about 2" and about 0.75" in the rear w/ custom Deaver coils and Icon rear shocks. Factory UCA's. The truck has been running this suspension of about 15k miles, no problems to this point.

I have 3 lifted Toyotas: an '07 Tacoma, a '12 Tacoma and this '13 SR5 T4R. This same shop did the lifts for all 3 vehicles, did the alignments for all 3 vehicles, same mechanic for all 3 vehicles. I've been doing business w/ them for about 4 years. They do good work, have never had a problem before.

Same shop, same alignment tech, brought the same vehicle to the same specs 15k miles ago and I had no problems - now the code. Yes, they have a modern Hunter machine that does zero point calibration. They did the zero point calibration twice with the machine, can't clear the code. Then they tried the manual zero point calibration twice w/ the the jumper wire, can't clear the code. Battery has been disconnected multiple times, no effect. Vehicle will go into 4wd/4lo, but no ATRAC.

Any ideas?

David

http://www.toyota-4runner.org/5th-g...celeration-sensor-zero-point-calibration.html

Using this link I tried to ZPC idk how many times. I then tried the actual 4th and directly bellow modules... thinking what’s the worst that could happen, blown fuse who knows.

So using the 5th and 13th slot did everything as explained. It worked perfectly. Zeroed out, went to test mode, drove it around, then did the multi terrain and dac.

Boom worked!

So idk if I’m just a lil slow and read it wrong but it’s g2g now!

 

[Jsenese]

Similar problem with my 2015... what was the fix for this?

I left in the shop overnight. There “master technician” will be there in the AM.

If they can’t figure it out I’ll bring it home and try the jumper wire method.

 

[Doza615]

Similar problem with my 2015... what was the fix for this?

I left in the shop overnight. There “master technician” will be there in the AM.

If they can’t figure it out I’ll bring it home and try the jumper wire method.

Hey wondering if you got this resolved. I had an alignment done after a lift and now the issue is the trac light stays on. Can’t get the down hill assist to come on either.

 

[Olfanbm]

That's a real bummer...

David, I hate to sound like a broken record here but if you have the time, I urge you to try performing the ZPC one more time by yourself. All you need is a relatively flat surface, one piece of wire and it literally takes 30 seconds once you memorize the few steps. There's also absolutely nothing you can screw up more (unless you jumper the two wrong pins, lol), so really nothing to lose at this point.

The reason I am so adamant about it is because all of the signs of an improper ZPC are there (no disrespect to your tech of course, this procedure is just really finicky IMO). If you had no C120A DTC going into this alignment there is no other reason it would magically appear, unless the signal between the DAC button and the master cylinder solenoid just happen to break recently.

Here is the thread in case you haven't had a chance to find it: Yaw Rate and Acceleration Sensor Zero Point Calibration - Toyota 4Runner Forum - Largest 4Runner Forum

Few tricks that I think will make your life easier is...don't worry about the drive straight ahead for 20 seconds part, until after you are done with all the steps. And also, don't worry about driving straight ahead...I've tried it every which way (forwards, backwards, in a circle, you name it) and none of them seem to make a difference.

I know the instructions seem daunting at first, but it really boils down to just a few simple steps. First you find the two pins on the OBD2 service port...now with the ignition in the ON position, you connected it and disconnect it quickly a few times, which will cause your slip light to come on (this signifies that you've successfully cleared all the data).

Now, turn it off, connect the two pins securely with the jumper wire and then turn the ignition switch back to the ON position; you should see the slip light start flashing rapidly shortly after (which means the ZPC data has been stored).

Turn it off again, leave the jumper connected, then turn it right back to the ON position. Now this part differs a tiny bit because I have crawl control and you have DAC, but I believe you just press your DAC button a few times to make sure the little "4runner driving down a mountain" indicator goes on and off in your gauge cluster every time you press it.

Turn off the ignition, remove the jumper wire, start her up and go for a spin around the block and you're done!

I really hope this resolves your issue, but if not, at least you're certain it's something that requires a trip to the dealer. Feel free to post or PM me if you get stuck on any certain steps, I'll try to walk you through it the best I can :cheers:

Excellent friend eddiebox your procedure solved my VSC light turning off after multiple attempts that did not turn on the DAC button