OEM 2009 Mercury Mariner Brake Booster

2009 Mercury Mariner Brake Booster Parts Questions & Experts Answers

• Q: How to service and repair the vacuum brake booster on 2009 Mercury Mariner?

  A: When repairing the vacuum brake booster start by taking the stoplamp switch off only after positioning the brake pedal at the resting state because trying to remove it with the plunger expanded creates switch damage. Once you remove the stoplamp switch you should throw away the booster push rod clevis-locking pin because it is a single-use component that works by squeezing the locking tabs then pulling it forward. To install new brake booster nuts follow the torque sequence of 23 Nm (17 lb-ft) after you remove and discard the existing four nuts. Disconnect the brake booster vacuum hose/check valve assembly while hybrid vehicles require removal of vacuum pressure sensor together with booster solenoid and booster travel sensor electrical connectors. The two master cylinder nuts must be removed before reinstalling them while new nuts need to be tightened to 30 Nm (22 lb-ft). You should avoid disconnecting the brake tube fittings because you need to gently push forward the brake master cylinder assembly for removing the brake booster. The proper installation of the stoplamp switch requires the brake pedal to remain at the resting position with attached push rod of the booster to prevent any damage or misalignment. The Multi-Calibration Routine must be performed based on scan tool instructions when working on hybrid vehicles.