P2747
Intermediate Shaft Speed Sensor B Circuit No Signal
Automatic transmission (speed sensor)
Generic OBD-II
Medium
What it means
P2747 means the transmission controller isn't receiving a signal from the 'B' intermediate shaft speed sensor. Without that speed input the module can't time shifts correctly, so you may get harsh or erratic shifting or a protective limp mode. It's usually a failed sensor, a wiring/connector fault, or debris on the sensor — the engine still starts and runs.
Medium
Can I keep driving? Yes but with care — losing a shaft-speed input can cause harsh or erratic shifts or limp mode; repair soon to avoid added wear.
Common symptoms
What you'll notice
- Harsh or erratic shifting
- Wrong-gear behavior or limp mode
- Poor shift quality or delayed engagement
- Check-engine light on
Common causes
Most likely first
- Faulty intermediate shaft speed sensor BLikely
- Open or shorted sensor wiringCommon
- Corroded or loose sensor connectorCommon
- Metal debris on the sensor tip or damaged reluctor/tone ringLess often
- Transmission control module fault (least likely)Less often
How to diagnose & fix
Work through it in order
- Check transmission fluid level and condition.
- Inspect the sensor connector and wiring for opens, corrosion, or chafing.
- Remove the sensor and check the tip for metal debris; inspect the tone ring.
- Back-probe and test for a speed signal while the shaft turns.
- Replace the speed sensor if it fails; consider the module only after wiring checks out.
FAQ
Quick answers
Is it safe to drive with P2747?+
Short-term, gently. Without this speed input the transmission may shift oddly or limp. Get it diagnosed soon to avoid extra wear.
Can I just clear P2747?+
You can, but a no-signal fault from a bad sensor or wiring returns quickly. Fix the sensor or circuit rather than relying on a clear.
Related codes
Often seen with P2747
Read & clear P2747 yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.
✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX