P0791Intermediate Shaft Speed Sensor A Circuit
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- 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. Ford uses P0791 as its only intermediate shaft code, for 'no or too little signal': while the vehicle drives under power (turbine at least 1500 rpm, output at least 650 rpm or 15 mph), the sensor reports below 250 rpm for 5 s – in the 2012 and 2020–23 summaries, with MIL. A Toyota bulletin for the U760 (Highlander, Venza, Camry 2009–10) replaces the countershaft sensor for P0791/P0793. GM's 10-speed has two such sensors but uses its own codes. Limp mode and harsh shifts follow.
- What you may notice
- Check engine light
- Limp mode or fixed gear
- Harsh or delayed shifts
- Follow-up pressure control codes (Toyota)
- Likely causes
- LikelyIntermediate shaft speed sensor faulty
- PossibleConnector or wire at the transmission (oil, corrosion, chafing)
- PossibleReluctor wheel damaged or debris on the sensor
- RareControl module
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Usually a job for a workshop.Typical cost: €150 – €600
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.