NOTE
The fire wire test switch substitutes and adjustable
potentiometer dial for the firewire loop.
E Set the knob of the potentiometer to its maximum setting, fully clockwise.
The potentiometer dial should read 10.0, representing 10 Kohms. Rerun the
system test and observe the firewire LED indicator on the engine AFES
T/A panel. If firewire LED remains illuminated on engine AFES T/A panel,
replace faulty engine AFES T/A panel (p 14-39). If the firewire LED does
not remain illuminated, go to step F.
F Test the firewire loop with a multimeter at the FIREWIRE TEST jacks as
follows:
1.
2.
Check the center wire continuity/resistance by placing
the multimeter probes in the red and green FIREWIRE
TEST jacks. The resistance must be between 95 and 180
ohms.
Check insulation resistance between the center wire and
the outer sheath by placing the multimeter probes in either
the black and red or the black and green FIREWIRE
TEST jacks. The resistance must be greater than 1
megohm. If the resistance tests of the firewire are within
the required ranges, go to step G. If firewire resistance
tests fail, perform FAULT LAMP REMAINS ON AUTO
LED IS LIT (p 2-306.10). Verify problem is solved.
2-306.5 Change 4
TM 9-2350-267-20
