sivikvtec

I just bought this car so I cannot be for sure if it was doing it before or not. Just replaced the front pads and rotors on my 99 GS400. I can duplicate the problem every time by putting the key in the ignition and turning it to the second position but not starting the car. I hear this electric hum come from the master cylinder, abs pump area. Runs for about 15 sec and then stops with a very metallic "clink" noise.

I hear this noise periodically as i drive, usually after coming to a stop. When I changed the pads, I did not pump the brake with the car not running, I pumped it after I started the car. The pedal went to the floor and slowly went back to normal after a few pumps. I read on another lexus site that doing this could have potentially ruined my "accumulator" and now it cannot build enough pressure, thus running the pump.

Cliffs:
Changed Pads and rotors, now periodic electric noise and clink sound from MC
Does it even if the car is not running, but the key is turned

Is this normal, or did I break something??

kao

I hear periodically electric noise and then clink too. It's annoying. I have read in repair manual that if you hear such noise from master cylinder rear, you have no reason to worry about your brake assist system else you have to worry.
So i am in confusion

sivikvtec

This might be normal. I suppose I'll ask the dealer when I'm in there getting the trans and diff fluids changed. Here is some info I've found on some other sites that is somewhat relevant.

http://www.lexusownersclub.co.uk/for...howtopic=55449
http://www.soarerworld.com/forum/sho...ght=brake+pads

I wonder if some of you guys can let us know if you are getting the same sound?

[ant]

yeah perfectly normal. mines always does it too. once you turn to the accessories position on the ignition it primes the system using the pump and then clicks off. then as you're driving it reprimes fairly often, depending how hard you brake and such.

it is meant to do that though. mine was braking dodgy and i got new pads and discs skimmed and it was 100x better and the accumulator pretty much made the same sound before and after so i do not think its an issue.

it is sort of annoying at first but you get used to it!