Chassis, generic

C0327 Encoder Motor

Check engine lightUsually off
EmissionsNot relevant
Drive cycleNot required
Limp modePossible

C0327 has no entry in the published J2012 tables, but GM documents it: the transfer case control module (TCCM) of 4WD trucks and SUVs uses it for the encoder that tells the module where the motor has turned the shift shaft. Dorman's instruction sheets for GM pickups and SUVs from 1998 to 2009, the Saab 9-7X included, describe it as a voltage outside the expected window on the encoder circuit; play in a worn shift shaft can also make the encoder report a false position. GM bulletin PIP5098 for the 2004–12 Colorado and Canyon links it to a Service 4WD message after cold or damp standing and points to ground circuit 550 of the encoder motor channels, terminal F7 of connector 2 in the underhood fuse block. PIP5094 lists the number among GM chassis codes.

Likely causes

Loose or corroded ground terminal for the encoder channels (GM circuit 550)
Damaged encoder harness or water in the motor connector
Encoder in the shift motor assembly defective
Worn shift shaft lets the encoder read a false position

Symptoms

  • Service 4WD message or flashing 4WD switch lamps
  • Transfer case does not shift or shifts only intermittently
  • Fault appears mainly on the first drive after cold or damp standing

Repair estimate

DifficultyMediumDIY possible
Parts and labour€20–600
Time0.5–2.5 h

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

Parts involved

encoder motortransfer case control moduleencoder position switch

Related codes

C0306C0310C0387

References: static.nhtsa.gov, dormanproducts.com, dormanproducts.com, static.nhtsa.gov.