Do The Brakes Set Codes When Flushing?

Just been thinking: I don't think disconnecting the 12 volt in advance will prevent codes, if there has been a pressure drop, say for example due to pushing the caliper piston back. When you next start up (with the 12 volt reconnected), there will be excessive brake pedal travel for the first push or two, and that's likely going to trigger codes.

OTOH, it might prevent some disastrous pressurizing event, say with the caliper swung up. The kind of thing that happens when you open the drivers door. Not sure, but I'd hate to have a piston ptoing out, thanks to that.

Also, regarding that method for disabling brake control (that I posted on page 1), I believe it means you have to have the car in ready mode (on), for the duration of the brake job. Unless I'm reading it wrong. That seems a little off-the-wall...

 

I read it in the manual to mean you have it in IGN-ON and not Ready. It lists putting it in Ready mode as one of the items that will cancel the ECB Invalid Mode.

In fact, to put it in Invalid Mode you are in IGN-ON and it never says to take it out of IGN-ON.

 

Ok. See the difference. It still bothers me a bit, but I guess it must be practical.

I might try getting it into that mode, just to see how it goes.

 

Connect a charge maintainer to your 12V if you plan to be in IG-ON for more than 10 minutes.

 

The reason for the IGN-ON is to be able to run the brake pumps, correct? I guess you are saying that this is a pretty good drain on the 12V battery ?

Would you recommend any of us DIY'ers to attempt to do the brake fluid replacement using the No Techstream method?

 

Post deleted, question has already been answered.

 

I'm hoping some brave soul will try before I get around to it

Really all I would want to do this go around is to remove lower caliper bolts and swing up the caliper, pull out the pads, and clean them up. But just my luck that would cause problems. Two problems I can think of:

1. The car detects low pressure afterwards, produces a code.

2. The dang pressurizing system starts up and pushes a piston out. (Don't know if this would happen, but just a bad thought)

Using a battery maintainer coupled with putting the car in that "disabled" mode sounds like a good idea.

 

LOL - my thoughts exactly. Let's see who can hold out the longest and have someone go first

That does sound like a good idea.

 

What's the old saying, two months in the laboratory saves two hours in the library?

Apparently, the booster/actuator takes up or releases fluid from the reservoir during operation. The middle mark is where it should be when inspected by the owner. The only way to see it at the Max level is to command Techstream to make it so. LOL go figure. See attached.

You all should be fine to do brake work with the battery disconnected.

 

The instruction for disabling brake control says to shift to Neutral, depress brakes 8 times in 5 seconds, shift to Park and repeat, repeat in Neutral, and finally back to Park. The only way you can shift out of Park is with the car completely on. In other words, the mode when it starts the engine after about 20 seconds.

Am I missing something? Seems like they're saying to do your brake job with the engine running...

 

From your post below:

(b) Select ECB (Electronically Controlled Brake system) Invalid Mode.

Perform the procedure listed below in 1 minute.

1. Turn the power switch on (IG) with park (P) selected and parking brake applied.
2. Select N and then depress the brake pedal more than 8 times in 5 seconds.
3. Push the P position switch and then depress the brake pedal more than 8 times in 5 seconds.
4. Select N and then depress the brake pedal more than 8 times in 5 seconds.
5. Push the P position switch.

(2) Check that the brake warning light / yellow is blinking.

It also says that putting the car in Ready mode will disable the Invalid Mode.

I agree with you that I thought that you could only put it in N when in Ready mode. Confusing. Could they be saying just put the joystick in the N position?

 

Is this saying that the brake fluid level should normally be at the middle mark ?

When I took mine in for low brake fluid level the dealership filled it back to the Max mark. That is where it is now.

 

Live and learn !! I tried IGN-ON this morning and you actually can shift in to N. You can shift between N and Park but you cannot shift D or R obviously since the HV battery is disconnected.

I would think that the reason is that as long as you have a good 12V battery you can shift to N even if you cannot get in Ready mode.

 

I don't understand the terms IGN-ON and Ready. Ok, there two states possible (or is it 3):

1. Push the power button without your foot on the brake.

2. Push the button a second time, with foot still off the brake.

3. Going back to the beginning: with your foot on the brake, push the power button.

#3 get's you going places. #1 is radio only.

Is #2 somewhere in between, the one that'll let you shift, but won't fire up the engine.

 

The way I read it, there is a chance that fluid will overflow if filled to Max when it should be at the middle. I guess you'll be the first to find out

Yes, #2 is aka IG or IG-On.

 

With my foot off the brake I pushed the On button twice, getting what looks like full dash display. But I couldn't shift out of park, just got a beep-beep each time I tried. Maybe something different in US spec.?

 

Did you have your foot on the brake when trying to shift?

 

No, I didn't. That was it! And after a couple of tries, I managed to get into the "disabled" mode, I think: the brake symbol on the dash was blinking. Again, its:

To Disable Braking System, within 60 seconds:

1. Without foot on brake, push Power button, twice.

2. Depress brake, shift to Neutral, release brake.

3. Depress brake pedal 8 times, in 5 seconds.

4. Hit Park button.

5. Depress brake pedal 8 times, in 5 seconds.

6. Depress brake, shift to Neutral, release brake.

7 Depress brake pedal 8 times, in 5 seconds.

8. Hit Park button.

If you're successful, the brake symbol on the dash should be blinking rapidly. To cancel, simply hit the Power button again, turning the car off.