Message Name:

LOW PRESSURE DETECTED

Message Code:

B3-008137

Associated CAS:

FIREX BTL 2 LOW
(Advisory)

FIREX Bottle 2 low pressure, or wire is open, or pressure switch has failed open, or FIREX Control Unit input monitoring circuit failed.

• FIREX Bottle 2
• Pressure Switch
• FIREX Control Unit (A91)
• Associated Wiring

Advisory Wire/Service Bulletin: None

Forum Articles/Infoservice/Newsletter: None

1. Verify pressure on the fire bottle gauge is reading normal pressure. Ref chart. If bottle is low, replace. If bottle pressure is normal continue to next step.
2. At the FIREX Control Unit (A91), plug A91P2, check pin 4 to ground for resistance. Should be less than 1 ohm.
3. If resistance is higher than normal, reconnect A91P2 and disconnect A110P1 from #2 Fire Bottle and jumper pins 2 to 3. Turn power on and verify FIREX BTL 2 (cyan) CAS is not present. If fault has cleared suspect faulty pressure switch internal of the fire bottle. If the pressure switch if suspected, follow the final steps of TASK 26-21-01-720-801 (there is some overlap between the fault isolation tasks and the procedure).
4. If fault is still present, verify wiring between pin 4 on plug A91P2 to pin 2 on A110P1 shows low resistance end to end.
5. If the above discrete wiring checks good, replace the FIREX Control Unit IAW TASK 26-11-01-000-801, TASK 26-11-01-400-801.