Some owners of 2016 Cadillac XTS vehicles may comment on a hard brake pedal on a cold start and/or a service brake assist message. The technician may find DTC C027B or P050F set in the EBCM. On some vehicles, the connector at the KR14 brake booster pump motor relay was not fully seated during installation. Inspect the connector for proper seating.

After seating the connector, deplete the brake booster vacuum by depressing the brake pedal several times with the engine off, and then restart the engine and confirm that the brake booster pump runs and that there is normal function of the brake pedal.

Example of a fully-seated KR14 connector.

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Information courtesy of Mitchell 1

Information for Technical Service Bulletins comes from ProDemand, Mitchell 1's auto repair information software for domestic and import vehicles. Headquartered in San Diego, Mitchell 1 has provided quality repair information solutions to the automotive industry since 1918.

About the Author

Mike Mavrigian | Editor

Mike received a BA degree from Youngstown State University in English Literature with a minor in Journalism in 1975.