Powertrain, generic (extended)

P283F Shift Fork C Position Circuit Intermittent

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

P283F stands for an unstable fork C position signal rather than a hard short or open. The rod 3 sensor in GM's Corvette dual-clutch gearbox runs at a carrier between 1500 and 2500 Hz; if the measured period puts it outside that band for 150 ms, the module records a Type A fault, as long as reference B and battery voltage are valid. Ford's TR9070 summary assigns the frequency check of rod sensor 3 to this code. Mercedes-Benz does not list it for the 8G-DCT, and Ford's DPS6 has no fork C at all. Because the signal survives most of the time, the cause is usually mechanical stress on the wiring: a connector that moves with engine rocking, corrosion on a terminal or a cracked insulation near hot parts. Shifts may falter only now and then.

Likely causes

Fork C connector working loose under engine movement
Corroded terminal causing signal dropouts
Cracked insulation near hot components letting noise in

Symptoms

  • Occasional stutter or delay on even-gear shifts
  • Warning lamp appears only now and then

Repair estimate

DifficultyShop_onlyWorkshop job
Parts and labour€100–2,500
Time1–6 h

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

Parts involved

shift fork cshift fork position sensor cwiring harness

Related codes

P283BP283DP283EP283CP283A

References: gsi.ext.gm.com, fordservicecontent.com.