DTC P1A1B: Brake System Control Module - Forced Engine Running

2010 Mercury Mariner Hybrid, AWDSECTION DTC P1A1B: Brake System Control Module - Forced Engine Running
WARNING: This page is about a different car, the 2011 Mercury Milan, 2011 Lincoln MKZ, 2011 Ford Fusion, 2010 Mercury Milan, and 2010 Ford Fusion. However, it is still accessible from the selected car via links, so may be relevant.
P1A1B - BRAKE SYSTEM CONTROL MODULE - FORCED ENGINE RUNNING

Description:  This DTC indicates the antilock brake system (ABS) module requested the engine on.
Possible Causes: 
  • Intake air system leak
  • Positive crankcase ventilation (PCV) system
  • Vacuum leak
  • Vacuum pump
  • Vacuum pump circuit
Diagnostic Aids:  Check for any unmetered air leaks. Diagnose any air intake system related DTCs.
Application  Key On Engine Off  Key On Engine Running  Continuous Memory 
All Refer to the Description, Possible Causes and Diagnostic Aids for the DTC in table
RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • You smell fuel, burning insulation, or see smoke.
  • Brakes feel soft, pull hard to one side, or make grinding noises.
  • The engine overheats, stalls repeatedly, or misfires under load.
  • You are missing required tools, torque specs, or safe lifting equipment.
  • You are not confident in the next step or safety outcome.