Powertrain, generic (extended)

P2746 Intermediate Shaft Speed Sensor B Circuit Range/Performance

Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modePossible

P2746 means the sensor B signal exists but does not make sense. GM's 2023/24 dual-clutch TCM uses it for the clutch 2 speed sensor: with that clutch fully closed and no microslip, its speed must equal engine speed, and a gap of 150 rpm or more for 1.1 s sets the code; further tests compare it with the speed derived from the output shaft and watch synchronizer speed during gear engagement (above 200 rpm for 50 ms). GM lists it as Type A, so the MIL comes on at the first failure. Ford's 2024 summary bundles three checks of sensor B here: dropouts (800 rpm lost within 10 ms, ten times), noise (2,500 spikes of 300 rpm within 50 ms) and a mismatch with gear and other sensors lasting 2.5 s.

Likely causes

Metal debris on the sensor tip or incorrect air gap to the reluctor
Interference or poor shielding causing signal spikes
Slipping clutch making the speed comparison fail
Damaged or loose reluctor ring on the shaft

Symptoms

  • Check engine light, often immediately
  • Jerky clutch engagement or erratic shifts
  • Limp-home mode or one half of the gearbox disabled

Repair estimate

DifficultyHardWorkshop job
Parts and labour€150–1,800
Time1–6 h

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

Parts involved

intermediate shaft speed sensor btone wheel

Related codes

P2745P2747P2748P0792P2750

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