P2748
Intermediate Shaft Speed Sensor B Circuit Intermittent
Transmission speed sensor
Generic OBD-II
Medium
What it means
P2748 means the intermediate shaft speed sensor 'B' signal is intermittent or erratic. The transmission relies on that speed input for shift timing, so shifts can become unpredictable when the signal drops out.
Medium
Can I keep driving? Usually drivable, but the intermittent signal can cause erratic or harsh shifting and occasional limp mode until it's repaired.
Common symptoms
What you'll notice
- Check-engine light on
- Erratic or harsh shifting that comes and goes
- Occasional limp mode
- Shift-timing glitches on some vehicles
Common causes
Most likely first
- Intermittent connection at a loose or corroded sensor connectorLikely
- Chafed or damaged wiring to the speed sensorCommon
- Faulty intermediate shaft speed sensorCommon
- Metal debris on the sensor tip or a damaged tone ringLess often
- TCM fault (least likely)Less often
How to diagnose & fix
Work through it in order
- Read codes and freeze-frame; note the conditions when the signal drops out.
- Wiggle-test the sensor connector and wiring while watching live data.
- Inspect the sensor tip for metal debris and check the tone ring.
- Replace the speed sensor if the signal is unstable.
- If wiring and sensor are good, suspect the TCM. Clear and road-test.
FAQ
Quick answers
Is it safe to drive with P2748?+
Generally yes, though shifting may feel unpredictable. Fix it before it progresses to a steady fault or limp mode.
Can I just clear P2748?+
Because it's intermittent it may clear briefly, but it returns until the loose connection or sensor is repaired.
Related codes
Often seen with P2748
Read & clear P2748 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