P0793 code meaning
Intermediate Shaft Speed Sensor A Circuit No Signal
Powertrain system Generic code P07xx codes Check engine light
What P0793 means
The intermediate shaft speed sensor measures a shaft between input and output – a countershaft on Toyota's U760 six-speed, the intermediate shaft behind the overdrive set on Ford's 5R110W. Together with turbine and output speed it lets the module check each gear stage and control clutch slip. P0793 means there is no pulse signal from the intermediate shaft sensor although the vehicle is moving according to other speeds. Toyota's bulletin for the U760 six-speed lists P0793 with P0717 and P0791 and replaces the countershaft sensor with a revised part. Ford reports the same fault under P0791 (below 250 rpm for 5 s). Note that a 2007 Allison table's 'P0793' for shift solenoid 1 low is a typo for P0973. Limp mode and check engine light follow.
P0793 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyMedium
- Typical labor1.5 to 3 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P0793
- Check engine light
- Limp mode
- Harsh shifts
- Accompanying codes P0717/P0791
Common causes of P0793
- Most likelySensor faulty (internal open circuit)
- PossibleWire open or connector loose
- Less likelyReluctor wheel or air gap
- Less likelyTransmission module
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Intermediate shaft speed sensorSensor wiringTransmission control module
What each part of P0793 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 7 | Area: transmission. |
| 93 | The exact fault in that area. |
What to do next
- Note P0793 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P0793
What does P0793 mean?
P0793 means "Intermediate Shaft Speed Sensor A Circuit No Signal". The intermediate shaft speed sensor measures a shaft between input and output – a countershaft on Toyota's U760 six-speed, the intermediate shaft behind the overdrive set on Ford's 5R110W. It is a generic code, so it means the same on every make.
Is it safe to drive with P0793?
Drive gently and only to a workshop. With P0793 the car can go into limp mode (reduced power) to protect itself.
Will P0793 fail an emissions test?
Yes, it can. P0793 is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P0793 to fix?
Difficulty: medium. A typical repair takes 1.5 to 3 hours of work. This is a job for a workshop.
Will P0793 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.