Traction light flashing under trail braking; TC and VSC are both off...

[CSG Mike]

The light next to the shift light in the upper right of the tach flashes whenever I try to trail brake. The same light stayed on solid when our BRZ was on the dyno, and went off as soon as we started driving normal after the dyno session, so the light is definitely directly related to wheel speeds/wheel speed sensors.

I have both traction and stability control fully off. Does anyone know how to eliminate this? It's interfering with trail braking, and forces the car to understeer instead of rotating the car how I want it to.

[Mitch]

I believe that's the electronic brake distribution. It's adjusting brake pressures at each corner to maximize how deep you can go before ABS kicks in. Great from a safety standpoint, but yes, can definitely mess with you on the track if you're not expecting it. Curious for an override as well.

Edit: looks like there's some noise for other Subarus about a combination of fuses you can pull to disable ABS and EBD (or just one and not the other).

[des]

Hold down only the button closest to you until both warning lights are illuminated. The system is fully off.

My understanding is that you turn off each button individually you get some kind of competition mode and the behavior you describe.

[Mitch]

Originally Posted by des

Hold down only the button closest to you until both warning lights are illuminated. The system is fully off.

My understanding is that you turn off each button individually you get some kind of competition mode and the behavior you describe.

EBD still steps in even with traction and stability control off. It only comes in when traction is lost under braking, hence why he get's it when trail braking.

[Dave-ROR]

Originally Posted by des

Hold down only the button closest to you until both warning lights are illuminated. The system is fully off.

My understanding is that you turn off each button individually you get some kind of competition mode and the behavior you describe.

He is already turning them off completely.

I'm guessing I'll experience this next monday.

[RiskyTrousers]

Does the Ecutek software have the ability to shut this off?

[des]

Originally Posted by Mitch

EBD still steps in even with traction and stability control off. It only comes in when traction is lost under braking, hence why he get's it when trail braking.

Ah, I misunderstood -- you're saying this is by design, rather than some kind of electronic malfunction or user error.

We've beat the snot out of the car and haven't encountered the flashing light in 100+ autocross runs and two track days.

But I may be doing it all wrong. Wouldn't be the first time.

[Mitch]

Originally Posted by des

Ah, I misunderstood -- you're saying this is by design, rather than some kind of electronic malfunction or user error.

We've beat the snot out of the car and haven't encountered the flashing light in 100+ autocross runs and two track days.

But I may be doing it all wrong. Wouldn't be the first time.

I've only had it step in a couple of times, but I definitely had everything disabled. Maybe I'm losing my mind, but I've heard others talk about it too. I think it really is only certain situations. Depending on your driving style, it may not step in at all. Do you brake heavily while turning, or try to keep the car pointed straight while braking?

[CSG Mike]

Mitch: Great info! Is there any technical literature available on this?

Des: I've run into the light during both track days. I'm currently running 215/45/17 Star Specs, but I also saw it when I did a few laps on the stock tires. At this point, I can make the light come on at will.

Additional info: I'm using staggered pads. Carbotech XP10 front and XP8 rear. Judging from how the paint on the front pads has burned off, and the rears are barely discoloring, the rears are not being used enough, and we are going to swap the rears up to XP10.

The light only kick in if I'm trail braking aggressively. If I trail brake in a manner that utilizies less than 100% of the front tire grip (even 95%), the light will not flash, and I don't get funky understeer when the rear should be coming out. The understeer is bad enough when the light is flashing that I was getting faster lap times by holding back a bit for the turns where trail braking is normally faster.

I've also seen the light blinking at SoWS going CW down a very bumpy chicane that requires trail braking (stock tires)

[Mitch]

Originally Posted by CSG Mike

Mitch: Great info! Is there any technical literature available on this?

Des: I've run into the light during both track days. I'm currently running 215/45/17 Star Specs, but I also saw it when I did a few laps on the stock tires. At this point, I can make the light come on at will.

Additional info: I'm using staggered pads. Carbotech XP10 front and XP8 rear. Judging from how the paint on the front pads has burned off, and the rears are barely discoloring, the rears are not being used enough, and we are going to swap the rears up to XP10.

The light only kick in if I'm trail braking aggressively. If I trail brake in a manner that utilizies less than 100% of the front tire grip (even 95%), the light will not flash, and I don't get funky understeer when the rear should be coming out. The understeer is bad enough when the light is flashing that I was getting faster lap times by holding back a bit for the turns where trail braking is normally faster.

I've also seen the light blinking at SoWS going CW down a very bumpy chicane that requires trail braking (stock tires)

Subaru's description of the system on their main website:

Smart Braking Systems BRZ's Anti-lock Braking System (ABS) prevents wheel lock-up and helps maintain driver control. Electronic Brake-force Distribution (EBD) balances braking, while Brake Assist can sense a panic-stop situation and apply full braking force to help stop faster.

Electronic Brake-force Distribution (EBD) optimizes the distribution of braking force between the front and rear wheels according to how the vehicle is loaded with passengers and cargo. And the Brake Assist system helps ensure maximum pressure is applied to the brakes as quickly as possible in an emergency situation.

That's all I have. I'll let you know if I find anything else.

[CSG Mike]

Hmmmm I may have to buy a service manual to figure out which fuse(s) to pull to disable this...

Gonna stop by a dealer today to see if they're even available yet.

[Sam Strano]

The light flashes when ABS is active. Most cars do this. My Z06 actually says "ABS ACTIVE" on the dash. My Z28 would flash the "Low Trac" light. This is nothing other than an indication that the ABS is working and in play.

[Spaceywilly]

Did you feel any intervention? Mine was doing this when I did an autocross, there was a 180 turn and every time when I was pulling away from there and starting to get loose the light would flash, but it didn't feel like it was doing anything so I ignored it. I think the manual calls it a slip indicator light.

[CSG Mike]

Is there a way to disable EBD? My objective and desire is to be able to control brake bias via compound choice.

The intervention came in the form of understeer in my case. Not sure how it manifested for others. Again, I'm running a more aggressive pad up front, which may be exaggerating the effect.