My Friends 2012 Ford Fusion Front caliper started to leak so we replaced it. AFTER caliper replacement I could NOT get the brakes to build pressure. I mean absolutely NO pressure what so ever. the master cylinder never went dry either to allow air in the system. I've read that I may need an ABS scan tool to bleed the brakes. Seems odd. PLEASE HELP. thanks

 

Did you get it figured out

 

If air was allowed to get into the system,, there is a good chance some might be trapped in the ABS module and lines. Scan tool make the job easier.

 

You have to bleed the system there are some great videos on how to do it if you replaced the caliper you need to open the bleeder valve and remove the brake Reservoir cap, allow brake fluid to run down through the caliper and pour brake fluid into the reservoir to prevent air getting into the master cylinder. Once fluid drops from the caliper have someone in the driver seat with the vehicle off pump the brake pedal 5 times and hold on the fifth pump wile you open the valve to release pressure and any possible trapped air. DO NO LET THE BRAKE PEDAL UP UNTILL THE VALVE IS CLOSED. Repeat step four or five time in order of passenger rear, driver rear, passenger front, driver front until satisfied with brake pressure. If that doesn’t work search for any possible leaks if none can be found the master cylinder may be junk.

 

sounds like you have a bad hydraulic control unit (HCU)