61-101-00802.EF1 Revision J
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(8) Connect aircraft battery.
(9) Close circuit breakers.
(10) Set aircraft fuel panel select switch to AUX / NAC and hold (if applicable).
a. The battery switch must be in the ON position for all airplanes except the model
C90 / C90A / B / GT / GTi / GTx.
b. The fuel quantity select relay or switch shorts the signal lead to return lead of MAIN
/ TOTAL or AUX / NAC that is not selected.
c. Due to continuity through diodes inside the probe, a short on RTN / GND shows as
a short on SIG / GND.
(11) Rotate INS TEST POINTS switch through remaining positions.
(12) Allow T/S to stabilize.
(13) Verify T/S reading is less than 50 nS at each position except SIG / RTN.
(14)
With switch rotated to SIG / RTN, verify a T/S reading of “1”.
(15) Return fuel panel select switch to MAIN / TOTAL.
a. If a test does not comply with specification, repeat test to verify readings.
b. If wrong reading remains, isolate fault by referring to aircraft wiring drawings and
disconnecting probes and / or the aircraft wiring at connecting junctions.
(16) This completes the Insulation Measurement Test.
(17) Set T/S ON / OFF switch to OFF.
Note:
If testing the opposite side, repeat procedure.
E. Disconnecting/Reconfiguring
(1) Open circuit breakers and turn battery switch OFF (if applicable).
CAUTION:
WHEN LOWERING OR RAISING THE FUEL PANEL, ENSURE
AIRCRAFT BATTERY IS DISCONNECTED.
(2) Disconnect T/S from the aircraft wiring.
(3) Reconnect aircraft wiring plug to Indicator.
(4) Return the aircraft to its original configuration.
