Powertrain, generic (extended)

P2847 Shift Fork C Position Sensor Incorrect Neutral Position Indicated

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

With P2847 the module has decided that the neutral signal from the fork C sensor cannot be trusted. Before a dual-clutch or automated manual box preselects a gear on a shaft, it must know that the other forks on that shaft are out; a false neutral could let two ratios mesh at once, so the module normally locks the affected gears out. No published manufacturer strategy uses P2847, so the code rests on the general CARB 13 CCR 1968.2 demand for plausible transmission inputs. In GM's Corvette software, the comparable static check for the third rod, which sits on the even shaft, is filed as P283C. Typical background: sensor or magnet moved during a transmission repair, positions never relearned, or a fork bent by a hard shift.

Likely causes

Fork C sensor or magnet repositioned during transmission work without relearn
Fork C bent, so neutral lies outside the learned band
Position sensor output drifting with temperature or age

Symptoms

  • Gears of fork C locked out, jumps between remaining ratios
  • Warning lamp and stored transmission code
  • Harsh or delayed shifts on the affected shaft

Repair estimate

DifficultyHardWorkshop job
Parts and labour€80–2,500
Time0.5–8 h

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

Parts involved

shift fork position sensor cshift fork ctcm

Related codes

P2846P2848P2845P283CP2852

References: law.cornell.edu, gsi.ext.gm.com.