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March 2021
Page 100 of 143
59812-K007 Rev 17
Business Confidential
Alternatively, an inspection of the engine event log, see section 3.6, will list the event:
Communications Fault Detector X
5.2.2.1
Single Detector in fault
Having established which detector is in fault it is necessary to establish the cause of the fault using the
following steps.
11.
Swap the detector with a known working detector.
12.
Reset the Control Unit.
13.
Wait for the communications fault to be indicated again.
If the fault indication remains at the original position return the swapped detectors to the initial
positions go to item 4
If the fault indication moves to the new position of the detector, the detector has failed and
should be replaced.
14.
Swap the detector cable with a known working cable at the Control Unit.
15.
Reset the Control Unit.
16.
Wait for the communications fault to be indicated again.
If the fault indication remains at the original position return the swapped cables to the initial
positions go to item 7
If the fault indication moves to the new position of the cable, the cable has failed and should be
replaced.
17.
Open the Control Unit lid
18.
Swap the detector harness connecting to the PCB with an adjacent harness. There is a push bar at
the side of the connector to release it, taking care not to damage the connection wires or the
connector pins/connections.
19.
Reset the Control Unit.
20.
Wait for the communications fault to be indicated again.
If the fault indication remains at the original position the Control Unit PCB has failed and should
be replaced.
If the fault indication moves to the new position of the cable, the cable has failed and should be
replaced.
5.2.2.2
All Detectors in fault
If all the detectors connected to the Control Unit are shown in communication fault complete the
following steps to identify the cause of the fault.
1.
the detectors.
all off, go to item 2.
2.
Remove the power from the Control Unit.
3.
Disconnect the detector cable from all the detectors.
4.
After 2 minutes apply the power to the Control Unit.
5.
Reconnect each detector one at a time, as each detector is connected check that the detector power
LED in on.
If the detector power LED is off the detector has failed and should be replaced.
6.
Once the failed detector has been disconnected / replaced remove the power from the Control Unit.
7.
After 2 minutes apply the power to the Control Unit.
8.
Continue reconnecting the remaining detectors as above until all detectors are reconnected to the
Control Unit.