As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LEFT BRAKE PEDAL DID NOT PROPERLY ACTUATE BRAKES. PEDAL WAS SOFT AND APPLIED LITTLE TO NO BRAKING ACTION ON LEFT BRAKE. CORRECTIVE ACTION. JAM NUT ON HYDRAULIC ELBOW TO BRAKE MASTER CYLINDER LOOSE. TIGHTEN JAM NUT TO ELBOW. NO LEAKS NOTED ON BRAKE MASTER CYLINDER. WORK COMPLIED WITH BY CESSNA C208B CHAPTER 32-41-00 AND 32-40-00.