ABS, ((!)) Break Lights, Battery Doesn't Regen When Braking

Good catch.

As you have Techstream and a Mini VCI, if you have not used it to go through the air bleed procedure, I would recommend doing that. There are two procedures on the menu, a shorter one when only wheel lines may have been opened, and a longer one for when air could have been aspirated into the underhood components. Since it seems your fluid got low enough to aspirate some air, the longer procedure would be the one to use.

I know you're just happy to have it working now and not buzzing, but it will work even better with the last of the air out.

-Chap

 

When I first got my Gen 3, I took it home and then let different amounts of air out of 3 tires. Using Techstream, I then noted down the IDs of the four sensors and, according to the pressures shown, which corners of the car they were on, then pumped them all back up. Since then, if I rotate tires myself, I just update the list with the new positions. If I take it to someone for rotation, I can do the air trick again as a way to confirm the rotation really happened and update the positions.

If Techstream is already showing you four transmitter IDs but one is showing a bogus pressure, then it doesn't sound like you have a find-the-ID problem, it sounds like you have a busted-transmitter problem, which you would need the tire unmounted to replace anyway.

-Chap

 

Yes, all zeros is normal, because the car doesn't ship with a sensor for the spare. If you bought one and installed it into the spare wheel, you'd be able to register it in the ID5 slot.

Yeah, the sensors aren't serviceable; even when their batteries run out, nothing to do but replace the whole thing. At least you know which wheel it's on, so you won't have to dismount 4 tires to find the flaky one.

The ABS actuator is the mound of valves and machinery under the hood, back under the windshield, attached to the master brake cylinder. The Antilock Brake System uses those valves to take over control of all four wheel brakes independently when it needs to for skid prevention.

And yes, that's the longer procedure I meant. The "usual" procedure is enough when the only places air could have entered would be maybe a little at the wheel ends of the brake lines. If you ever have to replace the ABS actuator, naturally you end up with air in that whole mess of chambers and valves, harder to bleed out. You didn't replace the actuator, but it seems like the level got low enough to let air be sucked in, which is pretty much the same deal.

By the way, one thing I ran into (with my cheapo clone Mini VCI) is that, in one part of the bleed procedure, it pumps up the accumulator pressure, bleeds it down, pumps it up, bleeds it down ... six times, I think. You don't have to do anything, just relax and listen to the whirrrrr...pfssssshhhh...whirrrrr...pfssssshhhh. But my MVCI had this annoying tendency to "lose communication with the vehicle" at random times, interrupting the procedure, sometimes when it was just almost done. Grrr. I'd just hit OK and it reconnects right away, but the procedure starts over from the top. By the time it finally managed to get all the way through (on, like, the sixth try), I think my system had been really well bled.

-Chap

 

I would go ahead and follow the instructions as given. You can probably use a rock, snowbrush handle, or the like to hold the pedal if you need to while dealing with the RR bleeder. You should, of course, have some fresh, compatible brake fluid on hand before you start, as you'll be bleeding some out.

-Chap