P0793
Intermediate Shaft Speed Sensor A Circuit No Signal
Transmission
Generic OBD-II
Medium
What it means
P0793 means the transmission control module is receiving no signal from intermediate shaft speed sensor A. Without that speed input the module can't correctly calculate gear ratios and shift timing, so shifts become harsh or erratic and the transmission may enter limp mode. It's usually a failed sensor, wiring fault, or damaged reluctor ring.
Medium
Can I keep driving? Often drivable but shifting can be harsh or erratic; get it diagnosed soon.
Common symptoms
What you'll notice
- Harsh or erratic shifting
- Slipping or delayed shifts
- May enter limp mode
- Speedometer or odometer glitches possible
- Check-engine or transmission warning light on
Common causes
Most likely first
- Faulty intermediate shaft speed sensorLikely
- Open or short in the sensor wiring or connectorCommon
- Corroded connectorCommon
- Damaged sensor reluctor ringLess often
- Transmission control module fault (less common)Less often
How to diagnose & fix
Work through it in order
- Read freeze-frame data and note any companion speed-sensor codes.
- Inspect the sensor connector and wiring for an open, short, or corrosion.
- Check the sensor air-gap and inspect the reluctor ring for damage.
- Test the sensor's output while the wheels or shaft turn.
- Replace the intermediate shaft speed sensor if it produces no signal.
FAQ
Quick answers
Is it safe to drive with P0793?+
Usually yes for short trips, but shifting may be harsh or erratic and it can enter limp mode. Have it diagnosed soon.
Can I just clear P0793?+
It returns as soon as the sensor signal is missing again. Repair the sensor or wiring to clear it for good.
Related codes
Often seen with P0793
Read & clear P0793 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