OBD-II trouble code
P0806: Clutch Position Sensor Circuit Range/Performance
The signal is present, steady and inside its electrical limits — and the module has decided it is still wrong. This is the one member of the clutch sensor family a voltmeter cannot settle, because every static reading passes.
Quick facts
- System
- Powertrain
- Category
- Transmission / Shift Control
- Severity
- Medium severity
- Drivable
- Usually safe to drive short-term
- Repair cost range
- $0 – $500
- DIY difficulty
- Intermediate DIY
What does P0806 mean?
Range and performance codes are a different species from circuit codes and P0806 is a clean example of the distinction. A circuit fault produces a value the module can reject on sight — nothing, or a value beyond what any real pedal position could produce. A performance fault produces a value that looks entirely legitimate. Nothing is shorted, nothing is open, the voltage sits comfortably between the limits, and the module still concludes the sensor is not telling the truth.
It reaches that conclusion by testing relationships rather than levels. The pedal has to reach a plausible minimum when released and a plausible maximum when pressed to the floor, and the distance between those two is the sweep the module expects to see. If the sweep is short, if the released position has drifted upward over the years, or if the value never quite returns to its rest point, the numbers are individually fine and collectively impossible. The module also cross-checks against evidence from elsewhere — engine speed decoupling from road speed says the clutch is genuinely disengaged, and a pedal signal that disagrees with that is a signal being contradicted by physics.
The consequence of that testing method is worth stating plainly, because it changes what a sensible diagnosis looks like. P0806 is the member of this family most often set by a purely mechanical change while every electrical component is in perfect condition. A pedal stop bolt that has been adjusted, a thick winter floor mat stacked on top of the original, a worn pivot bush that lets the pedal arm move sideways as well as up and down, a replacement clutch master cylinder with a pushrod set to a slightly different length — each of these moves the pedal without touching a wire, and the sensor faithfully reports the new geometry to a module that was taught the old one.
Which brings up the other thing that separates P0806 from its siblings: adaptation. Vehicles that use a continuous clutch position sensor almost always learn its endpoints rather than working from fixed values, because manufacturing tolerance across pedal boxes is wider than the accuracy the strategy needs. That learned data is what P0806 is measured against. So this code is both the one most often cured by running a relearn with no parts at all, and the one most often caused by fitting a correct new sensor and never teaching the module about it. If a sensor was replaced shortly before this code appeared, the adaptation is the first thing to check and the cheapest.
Common causes
- Clutch position adaptation never performed after a sensor, pedal box or hydraulic component was replaced
- Learned adaptation values corrupted or lost after a battery disconnection or module reprogramming
- Pedal rest position altered by a floor mat stacked on the original or by displaced carpet under the pedal
- Pedal stop or travel-limit adjustment changed, deliberately or during other footwell work
- Worn pedal pivot bush allowing lateral movement that the sensor reads as an inconsistent sweep
- Sensor element partially worn so that it no longer covers its full electrical range
- Replacement clutch master cylinder or pushrod of slightly different length changing where the pedal sits
- Sensor bracket bent or its mounting screws loose, moving the sensor relative to the pedal arm
- Magnet on a Hall-effect design shifted on the pedal arm, offsetting the whole reading
- Aftermarket pedal covers or heel mats preventing the pedal from returning fully
Symptoms
- Check engine light with no change in how the car drives
- Stop-start restarting the engine noticeably early or late in the pedal travel
- Hill-hold releasing before the clutch has taken up, causing a roll-back on inclines
- Bite point feeling different from how the driver remembers it, without any hydraulic symptom
- Code appearing shortly after clutch, master cylinder or pedal box work
- Code appearing after a battery replacement or module reprogramming with no mechanical work at all
- On automated manual and dual-clutch vehicles, inconsistent take-up or a slow, searching engagement
- No fault found on a static electrical test despite a stored code
Diagnostic steps
- 1.Ask what changed and when, before any testing. This code has a strong association with recent work — clutch hydraulics, a pedal box, a battery, a module reflash — and the answer often shortens the job to a relearn.
- 2.Record the reported clutch position with the pedal fully released and again with it pressed to the floor. Compare both against the manufacturer's specified values. A sweep that is short at one end tells you which end of the travel to investigate.
- 3.Check under the pedal for stacked floor mats, a thick aftermarket mat or displaced carpet. This costs nothing and is a genuine cause rather than a formality.
- 4.Confirm the pedal returns fully to its stop by hand. Lift it with a fingertip and feel whether it was already resting on the stop or was being held short of it.
- 5.Grasp the pedal arm and check for lateral play at the pivot. A worn bush changes the sensor's reading path without changing anything electrical.
- 6.Read the stored adaptation values with a capable scan tool if the vehicle exposes them. Values sitting at the extreme end of their adjustment range indicate the module has already run out of room to compensate.
- 7.Run the manufacturer's clutch position adaptation procedure and clear the code, then verify whether it returns. This is a legitimate diagnostic step here, not merely a fix.
- 8.Only if the relearn will not complete or will not hold should the sensor itself be suspected. Sweep the signal slowly across the full travel and look for a section where the value flattens or steps.
- 9.On automated manual and dual-clutch vehicles, check the clutch adaptation position against its wear limit. A learned engagement point near the end of its range means the friction material is worn and the sensor is reporting that accurately.
Repair cost
$0 – $500
The distribution of outcomes on this code is unusually skewed toward the cheap end. Removing an extra floor mat costs nothing. A clutch position adaptation performed at a shop is typically $80 to $160 and needs no parts at all, and on many vehicles it is the entire repair. If the sensor genuinely has to be replaced it is $30 to $220 for the part with 0.4 to 1.8 hours of labour, so $110 to $450 fitted, and the relearn must still be performed afterward. A worn pedal pivot bush is usually under $60 in parts but can be awkward to reach. Diagnosis is $90 to $150 and is money well spent, because the electrical tests that resolve the other codes in this family will all pass on this one.
Estimate your repair
Run the numbers for your vehicle
Open the Repair Cost Estimator with clutch position sensor replacement preselected. Adjust labor rate and vehicle category to fit your situation.
DIY vs shop
This is an intermediate DIY job. It usually involves diagnostic steps, specialty parts, and some careful work in tight spaces. If you have the tools and a service manual or trustworthy video for your specific vehicle, it is achievable in a weekend. Otherwise, a competent independent shop will be faster.