Brake help alarm

Code2

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Ok the short I had the lower passenger side piston freeze up on the caliper.

Removed the caliper and went and bought a new one reinstalled is back on connected the brake fluid line and then had someone pump the breaks inside 3 times then hold to floor while i cracked open the bleeder to get the air out.

after no air was coming out and just fluid i took it for a ride it stops but one thing i noticed was the side with the new caliper seems to be locking up when you slam on the breaks almost like the tire is sliding or skidding. that bothers me cause it never did that before

now here is where i am baffled

if you pump the pedal in drive or park I get this alarm

The better half of me says there is still air in the system causing the issue

Brake issue - YouTube

Ant ideas on what might have happened
 
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The alarm is the system thinking there is an issue when there isn't. Basically you're pumping the brakes as if you want to stop, but the vehicle sees that you are not moving and that their is sufficient braking pressure and system operation, so it gets confused and starts doubting its sensor inputs. If you do it enough times I wouldn't be surprised if it set a DTC, though its unlikely.

How long did you guys have the brake line disconnected, also are you sure that no air got into the master cylinder assembly?
 
black thanks for the response before seeing ur response I decided to try the same thing in my newer 4runner and it threw the same alarm so ur right its normal.

the caliper was off maybe 15 mins it was removed brought down the street maybe 5 mins away and a new one was on with in 15. I double checked for air again and it is fine no bubbles that alarm threw me off
 
black thanks for the response before seeing ur response I decided to try the same thing in my newer 4runner and it threw the same alarm so ur right its normal.

the caliper was off maybe 15 mins it was removed brought down the street maybe 5 mins away and a new one was on with in 15. I double checked for air again and it is fine no bubbles that alarm threw me off

Okay, the reason I ask is if an air bubble migrated up the line into the master cylinder unit and/or solenoid pack the vehicle may be thinking there isn't enough pressure in that caliper and over compensating.
 
The alarm is set because he is pumping the pedal enough to lower the accumulator pressure to a point that it can no longer safely slow the vehicle. At the point the accumulator pump runs to re pressurize the accumulator and the buzzer stops. Seems as if you either have a bad reman caliper or you didn't bed the pads properly and the "slam on the brakes" test you are doing is causing a slip..
 
Ok the short I had the lower passenger side piston freeze up on the caliper.

Removed the caliper and went and bought a new one reinstalled is back on connected the brake fluid line and then had someone pump the breaks inside 3 times then hold to floor while i cracked open the bleeder to get the air out.

after no air was coming out and just fluid i took it for a ride it stops but one thing i noticed was the side with the new caliper seems to be locking up when you slam on the breaks almost like the tire is sliding or skidding. that bothers me cause it never did that before

now here is where i am baffled

if you pump the pedal in drive or park I get this alarm

The better half of me says there is still air in the system causing the issue

Brake issue - YouTube

Ant ideas on what might have happened

[MENTION=70867]Code2[/MENTION], my experience with the 4Runner braking system is that you have to AGGRESSIVELY bleed them. I mean, once you have nothing but fluid flowing through the bleeder valves, you HAVE to do at least 10 more pedal pump/fluid squirts through the bleeders. I can almost guarantee, you will find a little bit more air during those 10 extra pumps. The T4R is the only vehicle that I have ever found that issue with.
 
[MENTION=70867]Code2[/MENTION], my experience with the 4Runner braking system is that you have to AGGRESSIVELY bleed them. I mean, once you have nothing but fluid flowing through the bleeder valves, you HAVE to do at least 10 more pedal pump/fluid squirts through the bleeders. I can almost guarantee, you will find a little bit more air during those 10 extra pumps. The T4R is the only vehicle that I have ever found that issue with.

Any of our hydraulically assisted master cylinders tend to be this way.

All the hybrids, FJ, Newer Tacoma (after about '10), 2nd Gen Tundra, 2nd Gen Sequoia, Land Cruiser, and 4Runner.
 
[MENTION=70867]Code2[/MENTION], my experience with the 4Runner braking system is that you have to AGGRESSIVELY bleed them. I mean, once you have nothing but fluid flowing through the bleeder valves, you HAVE to do at least 10 more pedal pump/fluid squirts through the bleeders. I can almost guarantee, you will find a little bit more air during those 10 extra pumps. The T4R is the only vehicle that I have ever found that issue with.

preacher i ended up pulling out the brake bleeding pump i use on my race bikes that it automatic to just suck everything out LOL crack the bleeder and let it run till there no air just to double check the old man way of bleeding. so its good now thanks

The pumping and alarm it what bothered me but when it did the same thing on my 2011 4runner and clarified here i forgot about it.
 

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