Narrative:

[I] received a cargo btl 1 EICAS and a dischrg light on the cargo fire panel. [I] followed the very lame QRH; which offered no guidance or explanation. [I] looked in the flight manual under systems for a better idea of the problem. Called dispatch and operations center; and it was agreed we needed to deviate to have the problem repaired before going into ETOPS airspace. Landed about 4;500 pounds overweight...smooth touchdown; had maintenance inspect...also as a precaution; the fire personnel followed us to the gate. Maintenance discovered a loose cannon plug on the pressure gauge of the number one bottle. Cleared the mrd and continued.

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Original NASA ASRS Text

Title: B767-300 Captain reported noticing an EICAS CARGO BTL 1 and DISCHRG light on; triggering a divert for maintenance action before they committed to their international over water leg.

Narrative: [I] received a CARGO BTL 1 EICAS and a DISCHRG light on the cargo fire panel. [I] followed the very lame QRH; which offered no guidance or explanation. [I] looked in the Flight Manual under systems for a better idea of the problem. Called Dispatch and Operations Center; and it was agreed we needed to deviate to have the problem repaired before going into ETOPS airspace. Landed about 4;500 LBS overweight...smooth touchdown; had Maintenance inspect...also as a precaution; the Fire Personnel followed us to the gate. Maintenance discovered a loose cannon plug on the pressure gauge of the number one bottle. Cleared the MRD and continued.

Data retrieved from NASA's ASRS site as of July 2013 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.