C0041: Brake Pedal Switch "B" (Subfault)

What it means

This code identifies a fault associated with brake pedal switch B. The specific failure depends on the diagnostic subtype.

How it works

Brake pedal switch B is a separate switch signal used by vehicle control modules to recognize brake-pedal operation. This subfault code flags a problem associated with that B signal, but the base code does not identify whether it is stuck, missing, or otherwise out of range.

Common causes

Most likely first.

1. Faulty brake pedal switch
2. Misadjusted switch
3. Damaged wiring or connector
4. Blown fuse
5. Brake control module fault

Symptoms

• Brake lights fail or stay on
• Cruise control may not work
• ABS or brake warning light

How to diagnose it

1. Read the brake-control and engine-control module codes and freeze-frame data to see when switch B disagreed with other brake signals.
2. Check whether the brake lights come on and go off consistently as the pedal is pressed and released, while observing switch B status on a scan tool if available.
3. Inspect the switch B mounting and adjustment at the pedal, plus its connector and wiring for looseness, damage, or corrosion.
4. Check the switch B fuse and test its supply, ground, and output circuit against the wiring diagram and manufacturer's procedure.
5. If adjustment and circuit tests pass, test switch B itself and then the brake-control module input.

Common fixes

• Adjust the brake pedal switch B position.
• Reconnect or clean its connector.
• Repair damaged switch B wiring or replace a failed fuse after correcting the cause.
• Replace brake pedal switch B if its output is faulty.
• Repair the brake-control module only if its input circuit is confirmed defective.

Can I keep driving?

Check the brake lights before driving; if they fail or stay on, other drivers may not see your braking and cruise control may behave unpredictably. Avoid using cruise control and address the fault promptly.