P0835 Code: Clutch Pedal Switch B Circuit High

What the P0835 code means

Some vehicles have two switches on the clutch pedal. One lets the engine start only when the pedal is pressed, and the other, switch B, is used by cruise control or to detect that the pedal is partway down.

It is a simple switch, so the computer sees either a high or a low voltage depending on the pedal position. The P0835 code is set when that signal sits above its maximum. A high signal usually comes from an open circuit or from an interrupted ground.

When switch B fails, you will usually notice that cruise control or the automatic start-stop system quits working.

To confirm the diagnosis, measure the continuity of each wire between the component connector and the computer connector with the key off. It should be under 1 ohm, and an infinite reading means the wire is open. If the wiring is good, measure the component itself: an infinite resistance confirms it is open inside.

P0835 code symptoms

• Check engine light on.
• Cruise control or start-stop system disabled.

Likely causes of the P0835 code

1. Loose or broken connector. This is the most frequent cause.
2. Signal wire or ground wire cut, so the signal climbs up to the reference voltage.
3. Switch open inside, with infinite resistance.
4. Short to 5 V or 12 V from rubbing against another wire in the harness.

How to diagnose the P0835 code step by step

1. Read the switch value on the scan tool and compare it with what you expect for the pedal position.
2. Inspect the connector for corrosion, water or loose pins.
3. Check power and ground with the key on: the reference should be correct and the ground voltage drop should be under 0.1 V.
4. Measure the signal with the connector plugged in and see whether it changes with the pedal.
5. Do a wiggle test on the harness with the scan tool in graph mode.
6. Check continuity of each wire to the computer (under 1 ohm).
7. Compare switches A and B on the scan tool while you press the pedal.

How to fix the P0835 code

• Repair the connector or the wiring.
• Replace the switch if the tests confirm it is bad.
• Correct the real condition if there is one.
• Clear the codes and verify with a road test.

Technical reference data

• The switch is powered from the computer. Check the values in the service manual for your vehicle.
• Reference values are only a guide, so look up the manufacturer data for your vehicle.
• Wire continuity should be under 1 ohm, and ground voltage drop under 0.1 V.

Brand-specific notes

The letter assignment (A or B) and the location of the switch change from one manufacturer to another, so check the manual for your vehicle before you start testing.

Because the clutch pedal moves every time you shift, the connector and wires behind the dash flex constantly. Check them before you buy a switch, since the P0835 code often traces back to a worn wire at that spot.

Frequently asked questions about P0835