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-   Technical Discussion and Customizing your H3 (http://www.elcovaforums.com/forums/forumdisplay.php?f=26)
-   -   Low motor type noise after brake application (http://www.elcovaforums.com/forums/showthread.php?t=8146)

BABHUMV 12-06-2005 12:53 AM

Does anyone else here a low motor type noise just after applying the brakes. It sound like it is coming from inside the dash. It is very low and can only be heard when the radio is off. I am thinking this is the ABS pump, but other cars I have driven I only here this noise if I used the ABS. The noise last about 1 second and is consistant every time after I apply the brakes.

BABHUMV 12-06-2005 12:53 AM

Does anyone else here a low motor type noise just after applying the brakes. It sound like it is coming from inside the dash. It is very low and can only be heard when the radio is off. I am thinking this is the ABS pump, but other cars I have driven I only here this noise if I used the ABS. The noise last about 1 second and is consistant every time after I apply the brakes.

f5fstop 12-06-2005 07:55 PM

The brake system on the H3 uses a high pressure accumulator versus a vacuum diaphragm for assist. The ABS pump motor will run even during base brake (non-ABS) operation, so this might be what you hear.
In many other ABS systems, the power assist is provided by vacuum, thus the pump only needs to run during ABS operation.
The pump motor is located in the engine compartment near the master cylinder.

Important information when working on the hydraulic system near the pump, accumulator, master cylinder, etc. With the ignition off, pump the brakes at least 20 times to decrease the pressure inside the accumulator. The accumulator will hold some high pressure, and brake fluid shot into your eye would be a big bummer.

BABHUMV 12-06-2005 10:11 PM

Thanks f5, I figured it was something like that.


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