Vehicle
2019 Ford Fiesta 1.0L Petrol
Title
C004000, Replaced Brake Light Switch
Complaint
The customer states the anti-lock brake system (ABS) light is on.
Cause
Confirmed customer complaint that the anti-lock brake system (ABS) light is on. Connected a scan tool and found code C004000 – Brake pedal switch A. With the key on, engine off, used the scan tool to monitor live data and depressed the brake pedal. Found the brake light switch parameter did not change state when the brake pedal was depressed. Performed an inspection of the brake light switch wiring harness and connectors, and found there were no loose connections or signs of damage. With the key on, engine off, used a multi-meter to check for the presence of voltage at the brake light switch and found voltage was present. Used the multi-meter to check for the presence of a short or open in the brake light switch wiring harness and found there were no shorts or opens present. With the key on, engine off, used the scan tool to monitor live data, connected a jumper wire across the brake light switch harness connector terminals and observed the brake light switch parameter changed state. These test results verified the brake light switch was faulty.
Correction
Replaced the brake light switch, cleared codes, performed a road test and verified the vehicle operated properly. The ABS light did not illuminate and no fault codes returned.