Lycoming TEO-540-C1A Maintenance Manual page 506

3. Disconnect wires from switch and disconnect ECU connector A001-P2. Measure resistance from A001-
P2 pin 48 to each wire and check for resistance as shown in the table below. Are the resistances
measured within the table limits? If yes, go to step 4. If no, but resistance is present and not within
table limits, replace the defective resistor in accordance with the aircraft maintenance manual. If no, and
circuit is open, go to step 5.
Switch Position
C
NORM
S
4. Complete a continuity and short circuit test of the switch. If the continuity or short circuit check fails,
replace the switch. If the continuity check is good, replace the ECU.
5. Complete a continuity test of the harness from the input side of each resistor to the ECU connector using
the engine system schematic. If the continuity check fails, isolate to affected harness by disconnecting
the airframe interface connection AF-P1. If the continuity fails between switch and AF-J1, repair cable
in accordance with aircraft maintenance manual. If the continuity fails between AF-P1 and ECU,
contact Lycoming Engines. If the continuity checks good, replace the ECU.
Fault ID 282
Primary: TIT1 External (Sensor Supply
Fault
Description
Secondary: -reserved-
Root Cause This fault implies that the Thermocouple offset voltage is deemed INVALID.
1. Run the engine in accordance with the engine and aircraft maintenance manuals. Is the fault active? If
yes, go to step 3. If no, go to step 2.
2. Using the FST, download active and service fault logs, then clear fault logs and monitor engine
operation for the fault to repeat.
3. Inspect TIT sensor, and lead for any damage (eg...burned, broken or frayed wires, cracked or broken
connectors, burned or broken sensors). Replace any damaged sensors per the "Sensor Replacement
Procedure" in Chapter 72-70. If no damage is found, go to step 4.
4. Inspect TIT harness connection for any damage (eg...burned, broken or frayed wires, cracked or broken
connectors). Contact Lycoming if harness damage is found. If no damage found, go to step 5.
5. Complete a continuity test of the harness from the harness sensor connector to the ECU connector using
the engine system schematic. If the continuity check fails, isolate to affected harness by disconnecting
the firewall connection, then contact Lycoming Engines. If the continuity checks good, replace the
sensor. If fault persists, replace the ECU.
Appendix D
Page 476
Troubleshooting Steps (Cont.)
Resistance Tolerance
330kΩ
1.01MΩ
3.21MΩ
Fault Group
Fault)
Troubleshooting Steps
TEO-540-C1A Engine Maintenance Manual
±10%
±10%
±10%
36 Fault Name
Fault Lamp
© 2018 Avco Corporation. All Rights Reserved
[FAULT: turbine inlet temperature 1
external]
None
November 2018