P1866 - Transmission Transfer Case System Concern Servicing Required

Repair Importance Level: 3/3
Repair Difficulty Level: 3/3   
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Possible causes

  • Faulty Transfer Case Shift Motor
  • Transfer Case Shift Motor harness is open or shorted
  • Transfer Case Shift Motor circuit poor electrical connection

Possible symptoms

  • Engine Light ON (or Service Engine Soon Warning Light)

P1866 Description

The Transmission Control Module (TCM) monitors the Transmission Transfer Case System. The TCM sets the OBDII code when the Transmission Transfer Case System is not to factory specifications.
OBDII Code P1866 - Transmission Transfer Case System Concern Servicing Required - AutoCodes.com

P1866 Information for specific makes

  • P1866 FORD Transmission Transfer Case System Concern Servicing Required
  • P1866 LINCOLN Transmission Transfer Case System Concern Servicing Required
  • P1866 MERCURY Transmission Transfer Case System Concern Servicing Required
  • P1866 MITSUBISHI High Side 2 System Overcurrent

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P1866 Comments

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