As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
BRAKE PRESSURE LIGHT: DURING TAXI OUT BOTH LOW PRESSURE AND ANTISKID LIGHTS ILLUMINATED ALONG WITH MASTER CAUTION. CIRCUIT BREAKERS DID NOT POP. USED EMERGENCY BRAKES TO STOP THE AIRCRAFT DUE TO COMPLETE LOSS OF BRAKE PRESSURE. // SIGNOFF // TROUBLE SHOT AND FOUND BRAKE RELAY TO BE WORKING INTERMITTENTLY REPLACED RELAY PN# MS24166-D2 IAW CE560XL AMM CH 24-50-03 OPERATIONAL CHECK GOOD AT THIS TIME OF INSTALLATION.