Brake Booster Power Usage ?

[cferry7]

1995 GMC Jimmy SLT 4.3L Vortek

 

While applying brakes the battery level drops from 12.7 volts to 11.6 volts.

 

A number of weeks ago while re-organizing my EVAP / Emiission hoses and / or

while I was connecting the Windshield Washer pumps this problem went away.

(While applying brake pedal the Battery Voltage monitor at cig lighter and Voltage meter on the dash-- the voltage would stay almost the same - a couple millivolts different.)

 

But now the 1.1 volt drop is back.

 

IS THIS NORMAL ? ? ?

 

[gmtech4]

Battery needs to be checked dude , alt output too

[00Silverado4x4]

Brake booster does not use any electrical power. The only power draw would be your brake pedal switch when you apply brakes. As was already said, you need to have your battery and or alternator tested.