Powertrain, generic (extended)

P2861 Shift Fork B Actuator Circuit Low

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

P2861 is set when a fork B actuator line reads near ground although the module has not switched it there, the classic signature of a short to ground. Ford's 2012 DPS6 summary assigns exactly this case on the motor of the drum for reverse and the even gears to P2861, and the 2014 Ford catalogue marks it as a MIL fault. Look for a motor phase rubbed through on a bracket, corrosion bridging a terminal to the shield, or a winding that has contacted the motor housing. The other circuit faults on this motor are kept apart: P285F for an open lead, P2862 for a short to battery voltage, P2836 for the driver chip. Once the output is disabled, the car typically drives on in gears 1, 3 and 5 only, without reverse.

Likely causes

Fork B motor lead rubbed through on a bracket or the case
Corrosion bridging a terminal to ground in the connector
Fork B motor winding shorted to its housing

Symptoms

  • Reverse not selectable
  • Engine lamp on, only odd gears in use

Repair estimate

DifficultyHardWorkshop job
Parts and labour€100–1,500
Time0.5–4 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

shift fork actuator bwiring harnesstcm

Related codes

P285FP2862P2860P285DP2836

References: newtonnet.co.uk, performanceparts.ford.com, law.cornell.edu.