American Airlines Logo Light Harness Troubleshooting

Competitors Required:

1

Description:

Competitors will troubleshoot the electrical harness of an inoperative logo light, following prescribed steps to perform wire checks and replace the harness.

References:

• Fluke 77/75/23/21 Series III Multimeter Instruction Sheet
• Electrical schematic (provided at the event)

Tools, Equipment, and Materials Provided:

• Digital Fluke Multimeter with leads

Snap-on provided tooling (qty one in each of two pallets unless otherwise indicated):

• Cannon plug pliers with grips (ATI508KG)

Procedures:

1. 1. Deactivate logo light system Select LOGO LIGHT SWITCH TO OFF, PULL AND COLLAR LOGO LIGHT CIRCUIT BREAKER.
   2. Remove electrical wiring harness.
   3. With electrical schematic and multimeter provided, perform the following wire checks to determine the status of each wire of the electrical logo light harness (These are the possible condition resistance, continuity, short, mis wire, Open.)

1. 1. 1. Wire Continuity Check
         1. Find the wire termination data. Refer to the WDM.
         2. Disconnect each connector on the circuit that must have a wire continuity check.

WARNING: EACH CONNECTOR ON THE CIRCUIT THAT MUST HAVE A TEST MUST BE DISCONNECTED. IF THE CONNECTORS ARE NOT DISCONNECTED, UNSATISFACTORY RESISTANCE INDICATIONS OR DAMAGE TO THE CONNECTOR CAN OCCUR.

1. 1. 1. 3. Measure the resistance on all wires. Make sure that each circuit has continuity from one end of the wire to the other end of the wire. Record your findings on the work sheet.

WARNING: DO NOT BEND OR PUT STRESS ON THE CONTACTS. DAMAGE TO THE CONNECTOR OR THE CONTACTS CAN OCCUR.

1. 1. 2. Insulation Resistance Check
         1. Select multimeter.

WARNING: DO NOT USE A MEGOHMETER FOR THE INSULATION RESISTANCE TEST OF THE ON-WING WIRING REPAIR. INJURY TO PERSONNEL OR DAMAGE TO THE AIRPLANE CAN OCCUR.

1. 1. 1. 2. Set the meter to the proper selection.
         3. Attach one meter test lead to a WIRE PIN assembly on the connector plug.

WARNING: DO NOT BEND OR PUT STRESS ON THE CONTACTS. DAMAGE TO THE CONNECTOR OR THE CONTACTS CAN OCCUR.

1. 1. 1. 4. Attach the other meter test lead to each WIRE PIN assembly on a wire that does not connect to the same WIRE PIN circuit. on both plugs

WARNING: DO NOT BEND OR PUT STRESS ON THE CONTACTS. DAMAGE TO THE CONNECTOR OR THE CONTACTS CAN OCCUR.

1. 1. 1. 5. Read the meter. Make sure that the resistance shown on the meter is open or 100 megohms.
         6. Repeat steps c) through e) for each WIRE PIN contact in the connector. Record your findings on the work sheet.

1. 1. 3. Back shell Check
         1. Attach the one meter test lead to the back shell.
         2. Attach the other meter test lead to the contact assembly on the wire that must have a test on the same back shell. WARNING: DO NOT BEND OR PUT STRESS ON THE CONTACTS. DAMAGE TO THE CONNECTOR OR THE CONTACTS CAN OCCUR.
         3. Read the meter. Make sure that the resistance shown on the meter is open or 100 megohms.
         4. Repeat steps a)-c) for each wire that must have a test.
      4. Record your findings for each wire to INCLUDE: CONDITION and METER READING on the work sheet.
   4. Replace harness with new one provided BY THE JUDGE
   5. Reactivate Logo light system.
   6. Verify Logo light operates.
   7. OPTIONAL: Complete bonus question worksheet.

Last updated: 12/17/2025