OBD-II trouble code
P0835: Clutch Pedal Switch "B" Circuit High
The clutch code that arrives disguised as something else entirely. Owners bring this one in complaining that cruise control has stopped working or that stop-start has quit — and the pattern of which features died and which survived identifies the failed switch before anyone opens the toolbox.
Quick facts
- System
- Powertrain
- Category
- Transmission / Shift Control
- Severity
- Medium severity
- Drivable
- Usually safe to drive short-term
- Repair cost range
- $60 – $400
- DIY difficulty
- Intermediate DIY
What does P0835 mean?
P0835 records the second clutch pedal switch circuit sitting at its upper level when the module expected the switch to be reporting. In circuit terms it is an open: the line is resting where it rests when nothing pulls it, and the switch has stopped pulling it.
The reason this code is worth its own page is not the electrical picture, which is ordinary, but the way it presents. Almost nobody arrives at a workshop with P0835 saying anything about the clutch. They arrive saying the cruise control has stopped working, or that the automatic engine stop-start has quit, or that hill-hold no longer holds. The clutch pedal itself feels normal, the gearbox is fine, the car starts and drives without complaint, and the connection between a switch under the pedal and a button on the steering wheel is not obvious to anyone who has not seen the wiring.
The link is agreement. The functions that go quiet are the ones a manufacturer will not run on a single opinion. Cancelling cruise control on the clutch, deciding whether to restart a stopped engine, holding the brakes on a hill while a driver finds the biting point — these are all cases where acting on one failed contact would be worse than not acting at all, so the software waits for both clutch switches to concur. Lose the second one and concurrence becomes impossible, so those features are withdrawn while everything that runs on the primary switch alone carries on untouched.
That gives a diagnostic shortcut that costs nothing. Before any testing, ask which functions have gone and which have survived. If the starter interlock still behaves correctly, and gear changes and idle are normal, but every feature that needs two-switch agreement has quietly disappeared, you have already established that the primary switch is healthy and the secondary one is not. That single observation narrows the job to one switch and one branch of wiring before a meter comes out — which matters, because the second switch is generally the more awkward of the pair to reach and time spent testing the accessible one is time wasted.
On stop-start vehicles the presentation deserves one extra note. Where the system uses this switch as part of its restart logic, the failure does not always show up as stop-start being disabled. Sometimes it shows up as the engine shutting down normally and then restarting a beat later than the driver expects, which owners describe as hesitation or a flat spot rather than as a fault. It is the same missing signal, reported in the language of how the car feels.
Common causes
- Contacts in the second switch failed open after long service
- Open circuit in the branch of wiring serving the second switch
- Connector unseated or a terminal spread on the secondary switch plug
- Corrosion in the switch body from moisture tracking down the pedal assembly
- Broken plunger or a retaining clip that has released the switch from its bracket
- Switch no longer reached by the pedal after clutch replacement changed the travel
- Cracked switch housing from over-tightening or from an earlier forced adjustment
- Poor or corroded ground shared by the pedal switch assembly
- Wiring broken where the pedal box loom flexes with pedal movement
- Module input failure, which is uncommon and only considered once the circuit is proven
Symptoms
- Cruise control unavailable or refusing to set, with no obvious cause
- Automatic engine stop-start disabled and staying disabled
- Engine restarting a beat late after a stop-start shutdown, felt as hesitation
- Hill-hold assist no longer holding on an incline
- Check engine light with the car otherwise driving perfectly
- Rev-matching unavailable on vehicles that offer it
- Starter interlock and gear changes completely normal, which masks the cause
- Owner complaint framed as a comfort feature fault rather than a clutch problem
Diagnostic steps
- 1.Start by cataloguing what still works. Features that need both clutch switches to agree being unavailable while single-switch functions behave normally is strong evidence for a secondary switch fault before any testing begins.
- 2.Confirm the starter interlock still operates correctly. If it does, the primary switch is healthy and the whole investigation belongs on the other side of the pedal bracket.
- 3.Watch both clutch switch parameters together through a slow full press and release. The channel that fails to move is the one to chase, and the comparison takes seconds.
- 4.Locate the second switch physically before testing anything. It is usually mounted further back and harder to see than the primary, and people routinely test the wrong one because it is the one they found.
- 5.Back-probe the secondary signal circuit at the switch and at the module in turn. Where the reading differs between the two ends is where the open lives.
- 6.Test the switch contacts directly with the connector removed, operating the plunger by hand. A switch that no longer makes contact reads the same as a broken wire and has to be ruled out separately.
- 7.Check whether the pedal still reaches the switch at all. A clutch replacement or a hydraulic repair can change the travel enough that a healthy switch is simply never operated.
- 8.Measure the ground shared by the pedal switch assembly. A corroded ground leaves the line resting high with every signal wire intact and is a common false lead toward the switch.
- 9.Verify the repair by confirming the withdrawn features have come back rather than by clearing the code alone. Those features returning is the evidence that the agreement the software wanted has been restored.
Repair cost
$60 – $400
Inexpensive once correctly identified, with the usual small premium for access. The switch is $15 to $95 in parts and takes 0.3 to 1.2 hours, so $70 to $260 fitted. Diagnosis runs $90 to $170. Repairing an open in the secondary branch of the pedal box loom is $120 to $400, most of that in getting to the wiring rather than in joining it. Where a shared ground turns out to be responsible, cleaning and re-securing it may add nothing beyond the diagnostic charge. Be sceptical of a quote that treats this as a transmission problem: nothing on this page requires the gearbox to be touched, and the fact that the complaint arrived as a cruise control or stop-start fault sometimes sends estimates in expensive directions.
Estimate your repair
Run the numbers for your vehicle
Open the Repair Cost Estimator with clutch position switch 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.