01 Limited brake booster failure

[_it___is_i]

No power brakes accompanied by lights and a buzzer. It's a hydraulic booster on the Limited and the dealer wants $1800 for a new one. Oriley's auto parts can ship it off and have it rebuilt for $350 which I'm probably going to do. My problem is I need to make certain that the booster is bad.

There was a recall on the accumulator and it was replaced by the previous owner. There was no noise or any other warning signs prior to failure and everything I've read says that they make noise before they fail. Does anyone no how to test the accumulator?

Could a bad ECU turn off the brake booster?

I don't know anything about hydraulic brake boosters, other than they're really expensive. Any ideas are appreciated.

 

[SirFrancisDrake]

What lights are coming on? ABS light? Buzzing is methodical or only happens when breaking?

 

[_it___is_i]

I went to pull out of a parking space and the ABS and brake lights came on. As soon as I moved the vehicle the buzzer started sounding. After I hit the brakes a couple of times they were dead, as in no power assist. The vehicle will barely stop if I put it in neutral and literally stand on the pedal.

I pumped the brakes, with the engine off, and started it while still pressing on the brakes and the pedal doesn't move. This is the only test that I know to do.

 

[earljuic3]

I am by no means an expert on this but I know the last time I bled my brakes and put new fluid in mine was buzzing until we got the fluid to the proper level. Have you checked for leaks?

 

[_it___is_i]

Yea, I had it towed to an import specialist today to get the trouble codes. Here's what the tech gave me:

63 ABS-ECU Internal Fault
53 Malfunction of Hydraulic Unit
51 ABS Valve Relay Circuit Open/Short

His conclusion is that the booster needs to be replaced. However, he said that the motor on the unit was receiving power but not functioning. In my FSM 53 is seizure of the pump motor. He wouldn't attempt to replace just the motor though. I'm going to call the dealer and find out if they sell the motor separately.

I had it towed back to my house. The cheapest they could do the job for was going to be somewhere north of $2k.

 

[_it___is_i]

It was definitely the pump motor.

http://i.imgur.com/4ijO3Jy.jpggood side of the shaft

http://i.imgur.com/dUi0X0K.jpgbad side

I only have a little over 170k miles and this truck has never been abused. Mitsubishi wants $800 for just the motor.

Really easy job though. If someone wants more than two hours for it tell them to go pound sand.