Brake pump control problem

[JuliusP]

Lots of these on the Forum but could not find one quite like mine.

My dashboard warning lights come on like a Christmas tree - Brake+ABS+VSC+TRAC. Dealer says I need a new Brake pump master assembly at about $2000+Lab. I am not sure I do.

Anyone know how the assembly actually functions? When in the FAIL mode the brakes still work. I still have brake assist (feels like vacuum assist) and no sponginess in the brake but don't have ABS, VSC and TRAC. The problem is intermittent which suggests it is likely an electrical connection or electrical component. Electrical connection would not be surprising as vehicle spent many years on salt roads of Michigan. It has a 2000 with 135,000 miles. Any suggestions?

Thanks,

JuliusP

 

[USA773]

I am dealing with the exact same problem today as well. Probably just the pump. Part only about $1100! Lots of good info on this site including recommendations to rebuild the motor.

I found a local shop that can do it and am taking him the pump tomorrow.

 

[Sandroad]

From reports here on MUD, the pump failure can be intermittent for some time before complete failure.

 

[PADDO]

Lots of these on the Forum but could not find one quite like mine.

My dashboard warning lights come on like a Christmas tree - Brake+ABS+VSC+TRAC. Dealer says I need a new Brake pump master assembly at about $2000+Lab. I am not sure I do.

Anyone know how the assembly actually functions? When in the FAIL mode the brakes still work. I still have brake assist (feels like vacuum assist) and no sponginess in the brake but don't have ABS, VSC and TRAC. The problem is intermittent which suggests it is likely an electrical connection or electrical component. Electrical connection would not be surprising as vehicle spent many years on salt roads of Michigan. It has a 2000 with 135,000 miles. Any suggestions?

Thanks,

JuliusP

So braking force - stopping power - is normal but you have multiple warning lights? Could be as simple as a failing speed sensor or any number of other issues. Have you pulled codes (or what codes did the dealer pull?) and when the problem is present does the brake accumulator pump/motor run? Check this by turning your ignition off and pump the brake pedal 40 times, ignition on and you should hear and feel the motor kick in for 30+ seconds. The fsm diagnostics and body of knowledge on how this system actually functions is pretty solid.

 

[schlite60]

I have the same problem with mine; I did do some research on possible other vehicles that use the same parts. I found some on flea-bay for around 350 dollars you can get a the whole master cylinder assy it is used and out of a wrecked vehicle. The possible donors would a 4 runner around the same year and the Lexus version of the 4runner; there is some others too. I needed another motor, accumulator and pump assy about a 3 banana job. i was using the Toyota part number for the whole pump, motor and accumulator assy. Mine will pump up for about 1-2 minutes then stop.