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ECM – No Communication Troubleshooting Tree
Symptoms
- No communication and engine will
not start - No communication and engine will start
- No communication related INSITE™ electronic service tool errors
- Communication with some ECMs but
not all ECMs on a multi-module engine.
How To Use This Tree
This troubleshooting procedure can be used to troubleshoot J1939 and J1587 data link communication issues between the electronic service tool and the ECM. There are four procedures that can be used to support this troubleshooting tree:
- Procedure 022-999 (Service Tools and Hardware – Overview) in Section F, in the appropriate electronic control system troubleshooting and repair manual.
- Procedure 019-165 (Data Link Circuit, SAE J1939) in Section 19 in the appropriate electronic control system troubleshooting and repair manual.
- Procedure 019-166 (Data Link Circuit, SAE J1587) in Section 19 in the appropriate electronic control system troubleshooting and repair manual.
The troubleshooting steps in this procedure build upon information obtained in previous steps. The troubleshooting steps
must be performed in the sequence specified in the troubleshooting procedure.
This troubleshooting procedure supports several engine families, therefore some instructions are stated in a general manner. Apply the requested procedures and actions to the specific engine family with the support of engine specific documentation that can be found in the Troubleshooting and Repair manuals for the specific engine family.
Shop Talk
Three basic principles were used to define and sequence the troubleshooting steps that are listed in this tree.
- Verify high level system operation prior to troubleshooting individual components of the system. The purpose for this is to learn from the behavior of the system in order to direct the next steps for troubleshooting.
- Use the Bench Top Harness to separate the ECM from the vehicle so the ECM can be isolated from vehicle issues that could be causing no communication.
- Use a second vehicle or a second ECM to isolate high level system issues before troubleshooting individual components of the system.
Troubleshooting Steps
STEPS | SPECIFICATIONS | |
---|---|---|
STEP 1. | INSITE™ electronic service tool error code check | |
STEP 1A. Check for INSITE™ electronic service tool error code 5023. | Is INSITE™ electronic service tool error code 5023 present? | |
STEP 1B. INSITE™ electronic service tool error code 5080 or 5081 check. | Is INSITE™ electronic service tool error code 5080 or 5081 present? | |
STEP 1C. INSITE™ electronic service tool other error code checks. | Are any INSITE™ electronic service tool error codes present other than 5023, 5080, or 5081? | |
STEP 1D. ECM password check | Does INSITE™ electronic service tool indicate the ECM is password protected? | |
STEP 2. | Initial data link adapter and INSITE™ electronic service tool check | |
STEP 2A. Initial data link adapter check | Are the communication lights on the data link adapter flashing? | |
STEP 2B. data link adapter reset check | Does the ECM communicate? | |
STEP 2C. Initial INSITE™ electronic service tool check | Does the ECM communicate? | |
STEP 2D. data link adapter verification check | Is an Inline or Inline I being use to communicate with the ECM? | |
STEP 2E. data link adapter firmware check | Is firmware version compatible with ECM? | |
STEP 3. | Bench communication setup checks | |
STEP 3A. Bench setup availability check | Is a bench setup available? | |
STEP 3A-1. Engine start check | ||
STEP 3B. Initial bench setup communication check | Does the ECM communicated using bench setup? | |
STEP 3B-1. Engine start check | ||
STEP 3C. Second vehicle or second ECM availability check for bench setup | Is second vehicle or second ECM available to connect to the bench setup? | |
STEP 3D. Initial bench setup functionality check | Does the second ECM communicate using bench setup? | |
STEP 3E. Troubleshoot bench setup | Does bench setup check OK? | |
STEP 3F. data link adapter replacement check | Does bench setup communicate with the second ECM using a replacement data link adapter? | |
STEP 4. | ECM power up circuit check | |
STEP 4A. Engine configuration check | Is the engine equipped with a fuel shutoff valve? | |
STEP 4A-1. Check fuel shutoff valve voltage | ||
STEP 4A-2. Coolant temperature sensor signal voltage check | ||
STEP 4B. ECM keyswitch voltage check | Is the keyswitch voltage within 1-VDC or vehicle system voltage? | |
STEP 4C. Check the ECM power and ground | Is the ECM battery supply voltage equal to the battery voltage? | |
STEP 5. | Initial electronic tool check | |
STEP 5A. Bench setup previously used for troubleshooting check | In Step 3 checks, was bench setup used to successfully communicate with the ECM? | |
STEP 5B. Second vehicle availability check for electronic tool | Is a second vehicle available to connect to the electronic tool? | |
STEP 5C. Initial electronic tool functionality check | Does the second ECM communicate using electronic tool? | |
STEP 6. | data link adapter power check | |
STEP 6A. data link adapter determination check | Is an Inline I data link adapter being used to communicate with INSITE™ electronic service tool? | |
STEP 6B. Check data link adapter power | Is the data link adapter power light on? | |
STEP 6C. Determination if communication is being attempted at OEM dash connector | Is the communication being attempted at the OEM data link dash connector? | |
STEP 6D. OEM data link dash connector voltage check | Is the voltage equal to or greater than 9-VDC? | |
STEP 6E. Check voltage at data link adapter auxiliary power supply | Is the voltage equal to or greater than 9-VDC? | |
STEP 6F. Check voltage at vehicle battery | Is the voltage equal or greater than 11-VDC? | |
STEP 6G. Computer serial port voltage check | Is a minimum of 5 VDC available? | |
STEP 7. | data link circuit check | |
STEP 7A. Check J1939 or J1587 circuits | Does the circuit check OK? | |
STEP 8. | Initial electronic tool check | |
STEP 8A. Second vehicle availability check for electronic tool | Is a second vehicle available to connect to the electronic tool? | |
STEP 8B. Initial electronic tool functionality check | Does the second ECM communicate using the electronic tool? | |
STEP 9. | Detailed electronic tool check | |
STEP 9A. Troubleshoot electronic tool hardware | Does the electronic tool hardware check OK? | |
STEP 10. | Serial cable and computer check | |
STEP 10A. Troubleshoot serial cable and computer | Do the serial cable and computer check OK? | |
STEP 11. | ROM boot ECM | |
STEP 11A. ROM boot tool availability check | Is the ROM boot tool available? | |
STEP 11B. ROM boot ECM | Does the ECM communicate? |
Guided Step 1 – INSITE™ electronic service tool error code check
Guided Step 1A – INSITE™ electronic service tool error code 5023 check | |
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Conditions
ActionCheck for INSITE™ electronic service tool error code 5023.
|
|
Is INSITE™ electronic service tool error code 5023 present? |
|
YES | NO |
No Repair | No Repair |
Guided Step 1B – INSITE™ electronic service tool error code 5080 or 5081 check | |
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Conditions
ActionCheck for INSITE™ error code 5080 or 5081.
|
|
Is INSITE™ electronic service tool error code 5080 or 5081 present? |
|
YES | NO |
Perform the ECM calibration download |
No Repair |
Repair complete
|
Guided Step 1C – INSITE™ electronic service tool other error code checks. | |
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Conditions
ActionAre any INSITE™ electronic service tool error codes present other than 5023, 5080, or 5081?
|
|
Are any INSITE™ electronic service tool error codes present other than 5023, 5080, or 5081? |
|
YES | NO |
See the INSITE™ Electronic Service Tool manual for troubleshooting guidelines. |
No Repair |
Repair Complete
|
Guided Step 1D – ECM password check | |
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Conditions
ActionDoes INSITE™ electronic service tool indicate the ECM is password protected?
|
|
Does INSITE™ electronic service tool indicate the ECM is password protected? |
|
YES | NO |
Enter correct password If password is unavailable, contact customer to request password information. If customer can |
No Repair |
Repair complete
|
Guided Step 2 – Initial data link adapter and INSITE™ electronic service tool check
Guided Step 2A – Initial data link adapter check | |
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Conditions
ActionTurn keyswitch on. |
|
Are the communication lights on the data link adapter flashing?
|
|
YES | NO |
No Repair |
No Repair |
Guided Step 2B – data link adapter reset check | |
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ConditionsINSITE™ electronic service tool connected to vehicle. ActionData link adapter reset check
|
|
Does the ECM communicate? |
|
YES | NO |
No Repair | No Repair |
Repair complete
|
Guided Step 2C – Initial INSITE™ electronic service tool check | |
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Conditions
ActionReboot INSITE™ electronic service tool PC.
|
|
Does the ECM communicate? |
|
YES | NO |
No Repair | No Repair |
Repair complete
|
Guided Step 2D – data link adapter verification check | |
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ConditionsNone ActionVerify if an Inline or Inline I data link adapter is being used to communicate with ECM. Reference Procedure 022-999 (Service Tools and Hardware – Overview) in Section F, for General Information – data link Adapters, in the appropriate electronic control system troubleshooting and repair manual for data link adapter identification information. |
|
Is an Inline or Inline I being used to communicate with the ECM? |
|
YES | NO |
No Repair | No Repair |
Guided Step 2E – data link adapter firmware check | |
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ConditionsNone ActionVerify data link adapter firmware version is compatible with ECM. Reference Procedure 022-999 (Service Tools and Hardware – Overview) in Section F, for General Information – data link Adapters, in the appropriate Electronic Control System Troubleshooting and Repair manual for data link adapter identification information. |
|
Is firmware version compatible with the ECM? |
|
YES | NO |
No Repair |
Load correct firmware version |
Guided Step 3 – Bench communication setup checks
Guided Step 3A – Bench setup availability check | |
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Conditions
ActionVerify bench setup is available. |
|
Is a bench setup available? |
|
YES | NO |
No Repair | No Repair |
Guided Step 3A-1 – Engine start check | |
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Conditions
ActionVerify if engine will start. |
|
Will engine start? |
|
YES | NO |
No Repair | No Repair |
Guided Step 3B – Initial bench setup communication check. | |
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Conditions
ActionAttempt to comunicate with the ECM using bench setup. |
|
Does the ECM communicate with bench setup? |
|
YES | NO |
No Repair | No Repair |
Guided Step 3B-1 – Engine start check | |
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Conditions
ActionDisconnect the bench top calibration cable from the ECM. Reconnect the ECM to the original engine or OEM wiring harness connector. Verify if the engine will start. |
|
Will the engine start? |
|
YES | NO |
No Repair | No Repair |
Guided Step 3C – Second vehicle or second ECM availability check for bench setup | |
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Conditions
ActionVerify if a second vehicle or second ECM is available to connect to the bench setup. |
|
Is a second vehicle or second ECM available to connect to the bench setup? |
|
YES | NO |
No Repair | No Repair |
Guided Step 3D – Initial bench setup functionality check | |
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Conditions
ActionAttempt to communicate with the ECM on the second vehicle or a spare ECM using bench setup. |
|
Does the second ECM communicate using bench setup? |
|
YES | NO |
No Repair | No Repair |
Guided Step 3E – Troubleshoot bench setup hardware | |
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Conditions
ActionTroubleshoot bench calibration cable, bench calibration harness, and serial cable.
|
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Does bench setup check OK? |
|
YES | NO |
No Repair |
Repair or replace bench calibration cable, bench calibration harness, or serial cable. |
Guided Step 3F – data link adapter replacement check | |
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Conditions
ActionTry to communicate with the bench setup using a replacement datalink. |
|
Does bench setup communicate with the second ECM using a replacement data link adapter? |
|
YES | NO |
Use replacement data link adapter. |
Issue with bench setup should have been found. Troubleshoot the bench setup again. |
Guided Step 4 – ECM power up circuit check
Guided Step 4A – Engine configuration check | |
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Conditions
ActionDetermine if the engine is equipped with a fuel shutoff valve |
|
Is the engine equipped with a fuel shutoff valve? |
|
YES | NO |
No Repair | No Repair |
Guided Step 4A-1 – Check fuel shutoff valve voltage | |
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Conditions
ActionMeasure the voltage from the fuel shutoff valve post to engine block ground. There are 12 and 24 volt systems, the fuel shutoff valve voltage needs to be within 1-VDC of the vehicle system voltage. |
|
Is the fuel shutoff valve voltage within 1-VDC of vehicle system voltage? |
|
YES | NO |
No Repair | No Repair |
Guided Step 4A-2 – Coolant temperature sensor signal voltage check | |
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Conditions
ActionMeasure the voltage across the two pins of the coolant temperature sensor on the wiring harness connector. Reference the wiring diagram or circuit diagram for connector pin identification. |
|
Is the coolant temperature signal voltage greater than 4.5-VDC? |
|
YES | NO |
No Repair | No Repair |
Guided Step 4B – ECM keyswitch voltage check | |
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Conditions
ActionMeasure the voltage from the keyswitch input SIGNAL wire of the wiring harness to engine block ground. Reference the wiring diagram or circuit diagram for connector pin identification. |
|
Is the keyswitch voltage within 1-VDC of vehicle system voltage? |
|
YES | NO |
No Repair |
Repair or replace the wiring harness that contains the keyswitch signal, or repair or replace the keyswitch, or check the battery connection. Reference Procedure 019-064 (Key Switch Battery Supply Circuit) in Section 19 in the appropriate troubleshooting and repair manual. See the Engine Performance Troubleshooting Tree in the appropriate troubleshooting and repair manual, if the no start condition is still present. |
Repair complete
|
Guided Step 4C – Check the ECM power and ground | |
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Conditions
ActionMeasure the voltage from each ECM battery SUPPLY (+) pin to all battery SUPPLY (-) pins in the wiring harness connector. Reference the wiring diagram or circuit diagram for connector pin identification. |
|
Is the ECM battery supply voltage equal to the battery voltage? |
|
YES | NO |
Call for authorization. Replace the ECM. Reference Procedure 019-031 (Electronic Control Module (ECM)) in Section 19 in the appropriate troubleshooting and repair manual. |
Repair or replace the wiring harness that contains the ECM battery SUPPLY (+) and battery SUPPLY (-) wiring. See the Engine Performance Troubleshooting Tree if no start condition is still present. |
Repair complete
|
Repair complete
|
Guided Step 5 – Initial electronic tool check
Guided Step 5A – Bench setup previously used for troubleshooting check | |
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Conditions
ActionIn Step 3 checks, was bench setup used to successfully communicate with the ECM? |
|
In Step 3 checks, was bench setup used to successfully communicate with the ECM? |
|
YES | NO |
ECM is OK, repair complete if communication is If communication is required through the OEM data link connector or harness continue to Step 6A. |
No Repair |
Guided Step 5B – Second vehicle availability check for electronic tool | |
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Conditions
ActionVerify a second vehicle is available to connect to the electronic tool. |
|
Is a second vehicle available to connect to the electronic tool? |
|
YES | NO |
No Repair | No Repair |
Guided Step 5C – Initial electronic tool functionality check | |
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Conditions
ActionAttempt to communicate with the ECM on the second vehicle using the same electronic tool hardware used on the problem vehicle. |
|
Does the second ECM communicate using electronic tool? |
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YES | NO |
No Repair | No Repair |
Guided Step 6 – data link adapter power check
Guided Step 6A – data link adapter determination check | |
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Conditions
ActionDetermine if an Inline I datalink adapter is being used to communicate with INSITE™ electronic service tool. Reference Procedure 022-999 (Service Tools and Hardware – Overview) in Section F, for General Information – data link adapter, in the appropriate electronic control system troubleshooting and repair manual. |
|
Is an Inline I data link adapter being used to communicate with INSITE™ electronic service tool? |
|
YES | NO |
No Repair | No Repair |
Guided Step 6B – Check data link adapter power | |
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Conditions
ActionNote: For all datalink adapters except Inline I. Attempt to communicate with INSITE™ electronic service tool and check to see if the data link adapter power light is on. Reference Procedure 022-999 (Service Tools and Hardware – Overview) in Section F, for General Information – data link Adapter, in the appropriate electronic control system troubleshooting and repair manual. |
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Is the data link adapter power light on? |
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YES | NO |
No Repair | No Repair |
Guided Step 6C – Determination if communication is being attempted at the OEM data link dash connector | |
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Conditions
ActionCheck to see if communication is being attempted at the OEM datalink dash connector. |
|
Is communication being attempted at the OEM data link dash connector? |
|
YES | NO |
No Repair | No Repair |
Guided Step 6D – OEM data link dash connector voltage check | |
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Conditions
ActionMeasure voltage across the SUPPLY and ground pins of the OEM datalink connector. Reference Procedure 022-999 (Service Tools and Hardware – Overview) in Section F, for In Cab data link Connector or 6-pin In Cab data link connector, in the appropriate Electronic Control System Troubleshooting and Repair manual for pin locations. |
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Is the voltage equal to or greater than 9 VDC? |
|
YES | NO |
Replace data link adapter |
No Repair |
Repair complete
|
Guided Step 6E – Check voltage at data link adapter auxiliary power supply | |
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Conditions
ActionMeasure the data link adapter supply voltage at the datalink adapter harness connector. Reference Procedure 022-999 (Service Tools and Hardware – Overview) in Section F, for 3-pin data link Cable, in the appropriate Electronic Control System Troubleshooting and Repair manual for pin locations. |
|
Is the voltage equal to or greater than 9-VDC? |
|
YES | NO |
Replace data link adapter. |
No Repair |
Repair complete
|
Guided Step 6F – Check voltage at vehicle battery | |
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Conditions
ActionMeasure vehicle battery voltage in all cases except if using an Inline I. If using an Inline I measure data link adapter voltage supply from computer. |
|
Is the voltage equal to or greater than 11-VDC? |
|
YES | NO |
Repair or replace damaged wiring. |
Clean the battery connections or replace the batteries. |
Repair complete
|
Repair complete
|
Guided Step 6G – Computer serial port voltage check | |
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Conditions
ActionNote: For Inline I only. Measure voltage across the SIGNAL ground pin and the data terminal ready pin and the SIGNAL ground pin and the request to send pin on the computer serial port. Reference Procedure 022-999 (Service Tools and Hardware – Overview) in Section F, for Serial Cable, in the appropriate Electronic and Control System Troubleshooting and Repair manual for pin locations. |
|
Is a minimum of 5 VDC available? |
|
YES | NO |
Replace data link adapter |
Contact PC administration support. |
Repair complete
|
Repair complete
|
Guided Step 7 – data link circuit check
Guided Step 7A – Check J1939 or J1587 circuits | |
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Conditions
ActionUse the following procedures to perform J1939 or J1587 circuit checks depending on the datalink circuit being used. Reference Procedure 019-165 (Data Link Circuit, SAE J1939) in Section 19 in the appropriate troubleshooting and repair manual. This procedure gives information for a complete resistance check, check for short circuit to ground, and check for short circuit from pin-to-pin. Reference Procedure 019-166 (Data Link Circuit, SAE J1587) in Section 19 in the appropriate troubleshooting and repair manual. This procedure gives information for a complete resistance check, check for short circuit to ground, check for short circuit from pin-to-pin, and voltage check. Reference Procedure 019-428 (Engine data links) in Section 19 in the appropriate troubleshooting and repair manual. Complete resistance check, check for short circuit to ground, and check for short circuit from pin-to-pin. |
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Does the circuit check OK? |
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YES | NO |
No Repair |
Repair or replace the harness with the data link problem, either the engine or OEM harness. |
Repair complete
|
Guided Step 8 – Initial electronic tool check
Guided Step 8A – Second vehicle availability check for electronic tool | |
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Conditions
ActionVerify if a second vehicle is available to connect to electronic tool? |
|
Is a second vehicle available to connect to the electronic tool? |
|
YES | NO |
No Repair | No Repair |
Guided Step 8B – Initial electronic tool functionality check | |
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Conditions
ActionAttempt to communicate with the ECM on the second vehicle using the electronic tool. |
|
Does the second ECM communicate using the electronic tool? |
|
YES | NO |
No Repair | No Repair |
Guided Step 9 – Detailed electronic tool check
Guided Step 9A – Troubleshoot electronic tool hardware | |
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Conditions
ActionPerform troubleshooting procedures for evaluating electronic tool hardware:
Reference Procedure 022-999 (Service Tools and Hardware – Overview) in Section F, in the appropriate troubleshooting and repair manual. Complete the following checks:
|
|
Does the electronic tool hardware check OK? |
|
YES | NO |
Communication issue found. |
Repair or replace damaged hardware. |
Repair complete
|
Guided Step 10 – Serial cable and computer check
Guided Step 10A – Troubleshoot serial cable and computer | |
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Conditions
ActionPerform troubleshooting procedures for evaluating the serial cable and computer. Reference Procedure 022-999 (Service Tools and Hardware – Overview) in Section F, in the appropriate troubleshooting and repair manual. Complete the following checks:
|
|
Do the serial cable and computer check OK? |
|
YES | NO |
Communication issue found |
Repair or replace damaged hardware. |
Repair complete
|
Guided Step 11 – ROM boot ECM
Guided Step 11A – ROM boot tool availability check | |
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Conditions
ActionVerify if ROM boot tool is available for specific ECM. |
|
Is the ROM boot tool available? |
|
YES | NO |
No Repair |
Call for pre-authorization Replace the ECM. Reference Procedure 019-031 (Electronic Control Module (ECM)) in Section 19 in the appropriate troubleshooting and repair manual. |
Repair complete
|
Guided Step 11B – ROM boot the ECM | |
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Conditions
ActionROM boot the ECM. Reference Procedure 019-427 (ECM ROM Boot) in Section 19 in the appropriate troubleshooting and repair manual. |
|
Does the ECM communicate? |
|
YES | NO |
Calibrate the ECM again. |
Call for pre-authorization Replace the ECM. Reference Procedure 019-031 (Electronic Control Module (ECM)) in Section 19 in the appropriate troubleshooting and repair manual. |
Repair complete
|
Repair complete
|