What was found
WHILE AT GATE WITH APU BLEED ON, LEFT PACK IN AUTO, ISO VALVE IN AUTO AND RIGHT PACK SWITCH OFF, RIGHT PACK LIGHT ILLUMINATED. DID NOT RESET ON RECALL DID NOT RESET WITH QRH. GROUNDED - YES. ACCOMPLISHED FIM 21-62 TASK 801 BIT OF BOTH CONTROLLERS #1 NO FAULTS #2 FAULTED TCV THIS PACK AND WOULD NOT RESET. ACCOMPLISHED FIM 21-62 TASK 831, REACCOMPLISHED BITE OF BOTH CONTROLLERS WITH NO FAULTS AND PACK LT EXTINGUISHED AND NO PACK LT ON RECALL. ALL OPS CKD NML.