STEP 7. Measure the sensor output voltage at brake booster pressure sensor harness side connector.
(1) Use special tool test harness (MB991348) to connect connector, and measure at pick-up harness.
(2) Start up the engine and let it idle for several minutes.
(3) Stop the engine, and turn the ignition switch to the "ON" position.
(4) Depress the brake pedal several times.
(5) Measure the voltage between terminal BPS5 line and ground.- The more frequently the brake pedal is depressed, the more the voltage is decreased.
(6) Turn the ignition switch to the "LOCK" (OFF) position.
Is the measured voltage normal?
Go to Step 9. Go to Step 8.