What was found
LEFT BLEED DUCT WARNING. FOLLOWED BY LEFT BLEED DUCT CAUTION. RAN QRH PROCEDURE RTF. NO EMERGENCY DECLARED. NO OVERWEIGHT LANDING. (FLIGHT 6214 - FILED CLOSED)INTERROGATED MDC FOUND B1 CODES 349537 AND 349536. FOLLOWED B1 CODES PER FIM 36-21-01 AND FOUND MT141 AND MT142 TO BE MAKING CONTACT WITH EACH OTHER. READJUSTED BOTH LOOPS TO NOT BE TOUCHING ANYMORE. RAN CURRENT BLEED LEAK EVENT LOCATION TEST IN REFERENCE TO AMM 36-21-00 AND ALL LOOPS NOW TESTED OK. RAN L PACK WITH APU IN REFERENCE TO AMM 21-50-00 FOR 30+ MINS AND NO L BLEED DUCT WARNING/CAUTION MESSAGE PRESENT. A/C OKAY FOR SERVICE AT THIS TIME.