ABS Pump? why do you gotta' pump every 5 seconds?

[infamousRNR]

HELP!!!!

my ABS pump seems to go on and pump every other time i apply the brakes!!

is this normal? i was reading another thread that talked about this silly pump but I'm convinced it shouldn't turn on and pump as often as it does with mine!

 

[19963.4lsr5]

Either its constantly doing a self test or for some reason its detecting wheel slippage.

Is your ABS light on or coming on?

There is a set of pins in the test connect by the intake manifold that will put it in diagnostic mode to see if any codes are present in the ABS controller.

 

[wc11]

You could have a bad ABS on one of the wheels sensor as well

 

[infamousRNR]

No light

Either its constantly doing a self test or for some reason its detecting wheel slippage.

Is your ABS light on or coming on?

There is a set of pins in the test connect by the intake manifold that will put it in diagnostic mode to see if any codes are present in the ABS controller.

there isn't any CEL light or ABS light.. breaking works fine. maybe even a little better than my 99' 4runner which the ABS kicked in a lot especially on gravel with bumps....

Another member suggested that it could be dirty brake fluid and to flush my brake system...

any ideas/opinions on this?

 

[whipkiller]

You need a louder stereo... I hardly ever even notice my pump.:music:

 

[vipergrhd]

Accumulator

Not too familiar about the Toyota ABS unit,but in my past experience most ABS have an Accumulator which holds high pressure gas in a chamber and it fills up with brake fluid during a self test and it keeps constant pressure which will be use in the event that ABS function is needed.When an accumulator start losing the charge it will no longer hold constant pressure in the chamber causing the pump trying to compensate for the drop in pressure.Hope this helps.