LEMON Manuals: Even more car manuals for everyone
Home >> Ford >> 2009 >> Flex Limited, FWD >> Repair and Diagnosis >> External Pages >> Different car >> Section 1706 (Anti-Lock Brake System - Vehicle Dynamic Systems) >> Diagnosis And Testing >> Anti-Lock Control - Hybrid >> Pinpoint Tests >> Pinpoint Test X: DTCs C101C:01 and 71 >> Normal Operation

Normal Operation

WARNING: This page is about a different car, the 2010 Mercury Milan, 2010 Lincoln MKZ, and 2010 Ford Fusion. However, it is still accessible from the selected car via links, so may be relevant.

When the combustion engine is not running, the electric vacuum pump is utilized to maintain a vacuum inside the brake booster. The ABS module controls the electric vacuum pump through the use of a mechanical relay located in the Battery Junction Box (BJB) and a solid state relay located in the auxiliary relay box. The mechanical relay provides power to the solid state relay. The solid state relay provides power to the electric vacuum pump motor. When the ignition is in the RUN position, the ABS module will close the mechanical relay. After the vehicle is started (the ready indicator is illuminated), the ABS module will activate the solid state relay as necessary to maintain a vacuum inside the brake booster.

Fused battery voltage is provided to the mechanical relay from BJB fuse 7 (40A) along circuit SBB07 (WH/RD). When the ignition switch is turned to the RUN position, the ABS module will ground the output side of the mechanical relay solenoid along circuit CBB30 (GY/BK). This will close the mechanical relay and send voltage to the solid state relay along circuit CBB07 (GN/BU). When it is necessary to build vacuum in the brake booster, the ABS module will ground the solid state relay along circuit CCB30 (GY/VT). The solid state relay will then send voltage to the vacuum pump and BJB fuse 37 (5A) along circuit CCB29 (WH/VT). The voltage passes through BJB fuse 37 (5A) and is delivered to the ABS module along circuit CBB37 (WH). The ABS module uses this voltage input to monitor the vacuum pump.

The logic internal to the solid state relay provides circuit protection for the vacuum pump circuit CCB29 (WH/VT). If a short to ground on circuit CCB29 (WH/VT) is detected, the relay will stop applying power to circuit CCB29 (WH/VT) until the short has been repaired.

If a vacuum pump DTC is set, the red brake warning indicator will illuminate and the combustion engine will run to supply vacuum to the brake booster.

This pinpoint test is intended to diagnose the following: 

scientia non olet · About LEMON Manuals