Model S4000T
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6.0 Troubleshooting
CAUTION -
Component level repair must be undertaken either by General Monitors
personnel, or by competent authorized service engineers. SMT PCB repair shall only
be performed at a General Monitors facility. Failure to comply with this requirement
will invalidate the warranty.
Be sure to inhibit or disconnect external alarm wiring before making any check which
might send the unit into alarm, if an alarm condition will cause a problem.
6.1 Fault Codes & Their Remedies
The Model S4000T has self-diagnostics incorporated into the microprocessor’s
program. If a Fault is detected, the output signal will drop to 0mA, the Fault relay will
de-energize and a Fault code will be displayed. The output signal will inform a remote
display module that the Model S4000T is in the Fault Mode. The display will indicate
a Fault code that can be viewed at the sensor site.
There are nine Fault conditions that are monitored by the microprocessor as follows:
6.1.1 F2 - Failed to Complete the Calibration
This Fault will occur if the unit is placed in the calibration mode and no gas has been
applied within twelve minutes, or if gas has been left on for more than 12 minutes.
ACTION – Remove gas, if present. Apply magnet to GM Logo on the cover to clear
fault. Re-calibrate, if necessary.
6.1.2 F3 - EPROM Checksum Error
This fault indicates that the contents of the Model S4000T’s program memory have
changed. This usually occurs when powering the unit up after a lightning strike or
large voltage transient on the power or signal lines to the unit.
ACTION - The unit must be returned to the factory or authorized service center for
repair.
6.1.3 F4 - Sensor Heater Open Error
This fault indicates that one of the sensor circuit leads is open-circuited.
ACTION - Check the integrity of all sensor connections, and ensure that the cable
from the Model S4000T to the remote sensor is not damaged. If this does not correct
the problem, replace the sensor and recalibrate.
6.1.4 F5 - Sensor Heater Shorted Error
This fault indicates that one of the sensor circuit leads is short-circuited.
ACTION - Check the integrity of all sensor connections, and ensure that the cable
from the Model S4000T to the remote sensor is not damaged. If this does not correct
the problem, replace the sensor and recalibrate.
6.1.5 F6 - Low Supply Voltage
This fault occurs if the supply voltage at the S4000T drops below +18.5VDC.
