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.
Medium severity. Can I keep driving?Drive gently to a repair shop. If it slips, you hear clunks, or it loses its gears, do not keep driving.
Symptoms
- Check engine light, often immediately
- Jerky clutch engagement or erratic shifts
- Limp-home mode or one half of the gearbox disabled
Most 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
What to check, in order
Start with the simplest. You can tick off each step.
Good to know
- Repair difficulty: hard
- It can trigger limp mode.
- It affects emissions.
What each character of P2746 means
- P: Powertrain: engine and transmission
- 2: Generic code: same on every make
- 7: Transmission
- 46: Specific fault in that system
Frequently asked questions
Can I keep driving with code P2746?
Drive gently to a repair shop. If it slips, you hear clunks, or it loses its gears, do not keep driving.
What causes code P2746?
The most common causes are: 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.
Related codes
- P2745Intermediate Shaft Speed Sensor B Circuit
- P2747Intermediate Shaft Speed Sensor B Circuit No Signal
- P2748Intermediate Shaft Speed Sensor B Circuit Intermittent
- P0792Intermediate Shaft Speed Sensor A Circuit Range/Performance
- P2750Intermediate Shaft Speed Sensor C Circuit Range/Performance
Sources
- gsi.ext.gm.com: 23OBDG07
- gsi.ext.gm.com: 24OBDG07
- fordservicecontent.com: OBDSM2400OUTPUT 16Jul2024 WSM final V2 MCS7001
Values and procedures vary by manufacturer. If it affects brakes, steering, fuel or high voltage, see a professional. Updated: 2026-11-04. How we build these pages.