Chip Detected Alert by ODM
TASK 79-35-00-810-808-A
Chip Detected Alert by ODM
1. Possible Causes
A. Fixtures, Tools, Test and Support Equipment
B. Referenced Information
3. Fault Confirmation
Subtask 79-35-00-710-059-A ** ON A/C NOT FOR ALL
Subtask 79-35-00-860-054-A ** ON A/C NOT FOR ALL
[Rev.8 from Aug 2018]
2026.04.04 04:40:52 UTC
Chip Detected Alert by ODM
1. Possible Causes
- SENSOR-OIL DEBRIS MONITORING [4074KS]
- W03 HARNESS [4087KS]
- PROGNOSTICS AND HEALTH MANAGEMENT UNIT [4609KS]
A. Fixtures, Tools, Test and Support Equipment
| REFERENCE | QTY | DESIGNATION |
|---|---|---|
| No specific | 1 | PLIERS - JAWED, SOFT |
| REFERENCE | DESIGNATION |
|---|---|
| TSM TASK 71-00-00-810-834-A | General Troubleshooting Guidelines for Additional Troubleshooting Information |
| TSM TASK 71-00-00-810-835-A | Component and Harness Intermittent Troubleshooting Procedure for Guidance Troubleshooting Intermittent Faults |
| AMM 70-70-00-910-803 | SPOP 6 - Cleaning of the Contact Points and Wiring Harnesses |
| AMM 73-21-00-710-807 | Test No.6 - EEC Operation Test (Idle Test) |
| AMM 73-21-63-000-802 | Removal of the Electronic Engine Control (EEC) Wiring Harness (W03) |
| AMM 73-21-63-400-802 | Installation of the Electronic Engine Control (EEC) Wiring Harness (W03) |
| AMM 77-31-01-000-801 | Removal of the Prognostics and Health Management Unit (PHMU) |
| AMM 77-31-01-400-801 | Installation of the Prognostics and Health Management Unit (PHMU) |
| AMM 78-36-00-010-802 | Opening of the Thrust Reverser Cowl-Doors |
| AMM 78-36-00-410-802 | Closing of the Thrust Reverser Cowl-Doors |
| AMM 79-00-00-210-809 | Visual Inspection of the Main Oil Filter Element for Contamination |
| AMM 79-00-00-281-802 | Inspection of the Magnetic Chip Collectors for Oil Contamination |
| AMM 79-35-21-000-801 | Removal of the Oil Debris Monitoring (ODM) Sensor |
| AMM 79-35-21-400-801 | Installation of the Oil Debris Monitoring (ODM) Sensor |
Subtask 79-35-00-710-059-A ** ON A/C NOT FOR ALL
A. Not Applicable
4. Fault IsolationNOTE: The Oil Debris Monitoring (ODM) Sensor has detected metallic particles in the oil that exceed allowable limits. The ODM sensor is installed between the main oil scavenge line (LR03) and the oil tank inlet housing located on the oil tank at the 9 o'clock position. The ODM sensor is monitored by the Prognostics and Health Management Unit (PHMU). The PHMU communicates the debris count to the Electronic Engine Control (EEC).
- Refer to the general troubleshooting guidelines for additional troubleshooting information (Ref. TSM TASK 71-00-00-810-834).
- Refer to the component and harness intermittent troubleshooting procedure for guidance troubleshooting intermittent faults (Ref. TSM TASK 71-00-00-810-835).
NOTE: Initial ODM alarms at the onset of a failure may not be supported by easily found particles on the magnetic chip collectors or oil filter element. Continued monitoring for subsequent alarms may be required.
NOTE: The ODM may "False Alarm" within a few hours after engine maintenance activities on the engine oil system due to maintenance induced contamination. Monitoring for subsequent alarms may be necessary to determine if the condition is actually an indication of a failure.
WARNING:
BE CAREFUL WHEN YOU DO WORK ON THE ENGINE AFTER SHUTDOWN. THE ENGINE AND ENGINE OIL CAN STAY HOT FOR A LONG TIME. IF YOU DO NOT OBEY THIS WARNING, INJURY CAN OCCUR.
WARNING:
REFER TO THE MSDS FOR ALL MATERIAL USED AND THE MANUFACTURER'S SAFETY INSTRUCTIONS FOR ALL EQUIPMENT USED. IF YOU DO NOT OBEY THIS WARNING, INJURY CAN OCCUR.
CAUTION:
MAKE SURE YOU REMOVE ELECTRICAL POWER FROM THE EEC BEFORE YOU REMOVE THE ELECTRICAL CONNECTORS. IF YOU DO NOT OBEY THIS INSTRUCTION, DAMAGE TO THE EEC CAN OCCUR.
Subtask 79-35-00-810-064-A ** ON A/C NOT FOR ALL A. Do the steps that follow:
(1) Open the thrust reverser cowl-doors AMM 78-36-00-010-802.
(2) Do the inspection of the magnetic chip collectors AMM 79-00-00-281-802.
(a) If the inspection is above the limits, remove the engine from service.
(b) If the inspection is within limits, continue to the next step.
(3) Do the visual inspection of the main oil filter element for contamination AMM 79-00-00-210-809.
(a) If the inspection is above the limits, remove the engine from service.
(b) If the chip collection inspection is within limits and the oil filter inspection is satisfactory, return the engine to service.
(c) Monitor the engine for the maintenance message to come back.
(4) If the maintenance message comes back or continues to be intermittent, go to the next step.
(5) If contamination is not found or the amount of contamination found and subsequent analysis does not support the oil debris monitoring sensor count readings, do the next step.
(6) Examine the W03 (4087KS) harness and connector P10 (4609KS-P10) - PHMU (4609KS) and connector P36 (4074KS-P36) - oil debris monitoring sensor (4074KS), for problems which are possible between the PHMU (4609KS) and the oil debris monitoring sensor (4074KS).
(a) Inspect for harness damage.
(b) Inspect for loose or damaged connectors.
1 Replace W03 HARNESS(4087KS) AMM 73-21-63-000-802 and AMM 73-21-63-400-802.
2 Do the Repair Confirmation, go to the Para. 4.B.
(7) If no problems are found with the harness or the fault continues and is not supported by oil system contamination analysis results, use a PLIERS - JAWED, SOFT to disconnect electrical connector P10 (4609KS-P10) from the PHMU (4609KS) and connector P36 (4074KS-P36) from the oil debris monitoring sensor (4074KS).
(a) Examine the pins and sockets (contacts) for alignment and damage. Look for contacts pushed rearward into the connector face. Replace parts as necessary.
(b) Clean the contacts with contact cleaner and clean cloth per SPOP 6. Blow dry with air (at less than 30 psi) across the connector face AMM 70-70-00-910-803.
(c) Reconnect electrical connector P10 (4609KS-P10) to the PHMU (4609KS) and connector P36 (4074KS-P36) to the oil debris monitoring sensor (4074KS).
(d) Do the Repair Confirmation, go to the Para. 4.B.
(8) If the fault continues and is not supported by oil system contamination analysis results:
(a) Replace SENSOR-OIL DEBRIS MONITORING [4074KS] AMM 79-35-21-000-801 and AMM 79-35-21-400-801.
(b) Do the Repair Confirmation, go to the Para. 4.B.
(9) If the fault continues:
(b) Do the Repair Confirmation, go to the Para. 4.B.
(10) If the fault continues:
(a) Replace the PROGNOSTICS AND HEALTH MANAGEMENT UNIT [4609KS] AMM 77-31-01-000-801 and AMM 77-31-01-400-801.
(b) Do the Repair Confirmation, go to the Para. 4.B.
Subtask 79-35-00-710-060-A ** ON A/C NOT FOR ALL (1) Open the thrust reverser cowl-doors AMM 78-36-00-010-802.
(2) Do the inspection of the magnetic chip collectors AMM 79-00-00-281-802.
(a) If the inspection is above the limits, remove the engine from service.
(b) If the inspection is within limits, continue to the next step.
(3) Do the visual inspection of the main oil filter element for contamination AMM 79-00-00-210-809.
(a) If the inspection is above the limits, remove the engine from service.
(b) If the chip collection inspection is within limits and the oil filter inspection is satisfactory, return the engine to service.
(c) Monitor the engine for the maintenance message to come back.
(4) If the maintenance message comes back or continues to be intermittent, go to the next step.
(5) If contamination is not found or the amount of contamination found and subsequent analysis does not support the oil debris monitoring sensor count readings, do the next step.
(6) Examine the W03 (4087KS) harness and connector P10 (4609KS-P10) - PHMU (4609KS) and connector P36 (4074KS-P36) - oil debris monitoring sensor (4074KS), for problems which are possible between the PHMU (4609KS) and the oil debris monitoring sensor (4074KS).
(a) Inspect for harness damage.
(b) Inspect for loose or damaged connectors.
NOTE: Loose connectors must be disconnected and examined for further wear or damage.
(c) If a problem is found with the harness or connectors: 1 Replace W03 HARNESS(4087KS) AMM 73-21-63-000-802 and AMM 73-21-63-400-802.
2 Do the Repair Confirmation, go to the Para. 4.B.
(7) If no problems are found with the harness or the fault continues and is not supported by oil system contamination analysis results, use a PLIERS - JAWED, SOFT to disconnect electrical connector P10 (4609KS-P10) from the PHMU (4609KS) and connector P36 (4074KS-P36) from the oil debris monitoring sensor (4074KS).
(a) Examine the pins and sockets (contacts) for alignment and damage. Look for contacts pushed rearward into the connector face. Replace parts as necessary.
(b) Clean the contacts with contact cleaner and clean cloth per SPOP 6. Blow dry with air (at less than 30 psi) across the connector face AMM 70-70-00-910-803.
(c) Reconnect electrical connector P10 (4609KS-P10) to the PHMU (4609KS) and connector P36 (4074KS-P36) to the oil debris monitoring sensor (4074KS).
(d) Do the Repair Confirmation, go to the Para. 4.B.
(8) If the fault continues and is not supported by oil system contamination analysis results:
(a) Replace SENSOR-OIL DEBRIS MONITORING [4074KS] AMM 79-35-21-000-801 and AMM 79-35-21-400-801.
(b) Do the Repair Confirmation, go to the Para. 4.B.
(9) If the fault continues:
NOTE: The oil debris monitoring sensor (4074KS) is connected to the PHMU (4609KS) by wires incorporating special construction features and shielding to prevent electrical noise from affecting sensor readings. Normal wire checks may indicate healthy wires but may not provide any indication of shielding condition.
(a) Replace W03 HARNESS [4087KS] AMM 73-21-63-000-802 and AMM 73-21-63-400-802. (b) Do the Repair Confirmation, go to the Para. 4.B.
(10) If the fault continues:
(a) Replace the PROGNOSTICS AND HEALTH MANAGEMENT UNIT [4609KS] AMM 77-31-01-000-801 and AMM 77-31-01-400-801.
(b) Do the Repair Confirmation, go to the Para. 4.B.
B. Repair Confirmation
(1) Do an engine run to idle for five minutes to confirm repair of this fault AMM 73-21-00-710-807.
(a) Check on ground scanning report, if the fault does not return you have fixed the problem.
5. Close-up(1) Do an engine run to idle for five minutes to confirm repair of this fault AMM 73-21-00-710-807.
(a) Check on ground scanning report, if the fault does not return you have fixed the problem.
Subtask 79-35-00-860-054-A ** ON A/C NOT FOR ALL
A. Put the aircraft back to its initial configuration.
(1) Make sure that the work area is clean and clear of tools and other items.
(2) Close the thrust reverser cowl-doors AMM 78-36-00-410-802.
(1) Make sure that the work area is clean and clear of tools and other items.
(2) Close the thrust reverser cowl-doors AMM 78-36-00-410-802.
EEC Wiring Harness