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Home >> Mitsubishi >> 2006 >> Lancer Evolution L4-2.0L DOHC Turbo >> Repair and Diagnosis >> Accessories and Optional Equipment >> Antitheft and Alarm Systems >> Testing and Inspection >> Symptom Related Diagnostic Procedures >> Inspection Procedures >> Inspection Procedure 1

Inspection Procedure 1

Communication with Scan Tool MB991958 is Impossible.

Part 1:




Part 2:






CIRCUIT OPERATION
The Immobilizer-ECU is energized by the MFI relay when the ignition switch is turned "ON". The ECM transmits a signal from scan tool MB991958 to the immobilizer-ECU as it is. In the same way, a signal from the immobilizer-ECU is also transmitted to scan tool MB991958 as it is.

TECHNICAL DESCRIPTION (COMMENT)
- This malfunction may be caused by a defective immobilizer-ECU, ECM, or a defect in the communication line between the immobilizer-ECU and ECM. If this malfunction appears when the MFI system and scan tool MB991958 can communicate each other, MFI system DTC P0513 will reset.
- If the MFI system is normal, the MFI relay can be determined as normal. In addition, if the MFI system and scan tool MB991958 can communicate each other, the circuits between the data link connector and the ECM can determined as normal.

NOTE: If this malfunction appears, MFI system DTC P0513 will be output.

TROUBLESHOOTING HINTS
- Malfunction of the immobilizer-ECU
- Malfunction of the ECM
- The wiring harness or connectors may have loose, corroded, or damaged terminals, or terminals pushed back in the connector

DIAGNOSIS

Required Special Tools:
- MB991958: Scan Tool (M.U.T.-III Sub Assembly)
- MB991824: Vehicle Communication Interface (V.C.I.)
- MB991827: M.U.T.-III USB Cable
- MB991911: M.U.T.-III Main Harness B

STEP 1. Using scan tool MB991958, read the MFI system diagnostic trouble code.

CAUTION: To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991502 or MB991958.

Use scan tool MB991958 to confirm the MFI system DTC.




1. Connect scan tool MB991958 to the data link connector.
2. Turn the ignition switch "ON" position.
3. Read the MFI system diagnosis code.

Q: Can scan tool MB991958 communicate with the MFI system? Is an MFI system DTC other than P0513 output?

YES : Go to Step 2.

NO : Refer to MFI Diagnosis in Computer and Control Systems.




STEP 2. Check immobilizer-ECU connector C-22 for loose, corroded or damaged terminals, or terminals pushed back in the connector.

Q: Is immobilizer-ECU connector C-22 in good condition?

YES : Go to Step 3.

NO : Repair or replace the damaged components). Refer to Harness Connector Inspection. Confirm that scan tool MB991958 communicates normally.

STEP 3. Check the battery power supply (MFI relay) circuit to the immobilizer-ECU. Measure the voltage at immobilizer-ECU connector C-22.




1. Disconnect immobilizer-ECU connector C-22 and measure the voltage available at the wiring harness side of the connector.
2. Turn the ignition switch to the "ON" position.




3. Measure the voltage between terminal 7 and ground.

Q: Is battery voltage (approximately 12 volts) present?

YES : Go to Step 6.
NO : Go to Step 4.




STEP 4. Check MFI relay connector B-12X for loose, corroded or damaged terminals, or terminals pushed back in the connector.

Q: Is MFI relay connector B-12X in good condition?

YES : Go to Step 5.

NO : Repair or replace the damaged components). Refer to Harness Connector Inspection. Confirm that scan tool MB991958 communicates normally.







STEP 5. Check the harness wires between immobilizer-ECU connector C-22 (terminal 7) and MFI relay connector B-12X (terminal 4).

NOTE: Also check intermediate connector C-123, joint connector C-21 and C-105 for loose, corroded, or damaged terminals, or terminals pushed back in the connector. If intermediate connector C-123, joint connector C-21 or C-105 is damaged, Repair or replace the damaged component(s). Refer to Harness Connector Inspection.

Q: Are the harness wires between immobilizer-ECU connector C-22 (terminal 7) and MFI relay connector B-12X (terminal 4) in good condition?

YES : There is no action to be taken.

NO : Replace damaged components). Confirm that scan tool MB991958 communicates normally.

STEP 6. Check the ground circuit to the immobilizer-ECU. Measure the resistance at immobilizer-ECU connector C-22.




1. Disconnect immobilizer-ECU connector C-22 and measure the resistance available at the wiring harness side of the connector.




2. Measure the resistance between terminal 3 and ground.

Q: Is the resistance less than 2 ohms?

YES : Go to Step 8.

NO : Go to Step 7.







STEP 7. Check the harness wire between immobilizer-ECU connector C-22 (terminal 3) and ground.

NOTE: Also check joint connector C-06 for loose, corroded, or damaged terminals, or terminals pushed back in the connector. If joint connector C-06 is damaged, Repair or replace the damaged components). Refer to Harness Connector Inspection.

Q: Is the harness wire between immobilizer-ECU connector C-22 (terminal 3) and ground in good condition?

YES : There is no action to be taken.

NO : Repair or replace the damaged components).
Confirm that scan tool MB991958 communicates normally.




STEP 8. Check ECM connector C-117 for loose, corroded or damaged terminals, or terminal pushed back in the connector.

Q: Is ECM connector C-117 in good condition?

YES : Go to Step 9.

NO : Repair or replace the damaged components). Refer to Harness Connector Inspection. Confirm that scan tool MB991958 communicates normally.







STEP 9. Check the harness wires between immobilizer-ECU connector C-22 (terminal 5) and ECM connector C-117 (terminal 98).

NOTE: Also check intermediate connector C-124 for loose, corroded, or damaged terminals, or terminals pushed back in the connector. If intermediate connector C-124 is damaged, Repair or replace the damaged components). Refer to Harness Connector Inspection.

Q: Are the harness wires between immobilizer-ECU connector C-22 (terminal 5) and ECM connector C-117 (terminal 98) in good condition?

YES : Go to Step 10.

NO : Repair or replace the damaged components).
Confirm that scan tool MB991958 communicates normally.

STEP 10. Replace the immobilizer-ECU or ECM.
Replace the immobilizer-ECU or ECM.

Q: Did the communication with the scan tool become possible after replacing the immobilizer-ECU or the engine control module?

YES : Register the password (secret code) and encrypted code. Confirm that scan tool MB991958 communicates normally

NO: Go to Step 11.

STEP 11. Recheck for malfunction.

Q: Is a malfunction eliminated?

YES : The procedure is complete. (If no malfunctions are found in all steps, an intermittent malfunction is suspected. Refer to How to Use Troubleshooting/Inspection Service Points -How to Cope with Intermittent Malfunction).

NO : Replace the immobilizer-ECU or ECM.


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