Inspection Procedure 5: Keyless Entry System Does Not Work: Diagnosis

WARNING: This page is about a different car, the 2012 Mitsubishi Lancer. However, it is still accessible from the selected car via links, so may be relevant.

Required Special Tools:

MB992006: Extra fine probe
MB991223: Harness set
MB991958 Scan Tool (M.U.T.-III Sub Assembly)
- MB991824: Vehicles Communication Interface (V.C.I.)
- MB991827 M.U.T.-III USB Cable
- MB991910 M.U.T.-III Main Harness A

STEP 1. Using scan tool MB991958, check for CAN bus the 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 MB991958.
1. Connect scan tool MB991958. Refer to "HOW TO CONNECT SCAN TOOL (M.U.T.-III) ."
2. Turn the ignition switch to the "ON" position.
3. Diagnose the CAN bus line.
4. Turn the ignition switch to the "LOCK" (OFF) position.
  Q: Is the CAN bus line found to be normal?
  1. YES: Go to Step 2.
  2. NO: Repair the CAN bus line (Refer to DIAGNOSIS ).
    
    Fig 1: Connecting Scan Tool To Data Link Connector
    Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
STEP 2. Using scan tool MB991958, read the 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 MB991958.
1. Connect scan tool MB991958. Refer to "HOW TO CONNECT SCAN TOOL (M.U.T.-III) ."
2. Turn the ignition switch to the "ON" position.
3. Check whether the WCM related DTC is set.
4. Turn the ignition switch to the "LOCK" (OFF) position.
  Q: Is the DTC set?
  1. YES: Diagnose the WCM. Refer to DIAGNOSTIC TROUBLE CODE CHART .
  2. NO: Go to Step 3.
    
    Fig 2: Connecting Scan Tool To Data Link Connector
    Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
STEP 3. Check the power supply system
With the ignition switch in the LOCK (OFF) position, check if the following function operates normally:
- Headlights
- Hazard warning light
  Q: Is the check result normal?
  1. YES: Go to Step 4.
  2. NO: Refer to MALFUNCTION OF ETACS-ECU POWER SUPPLY CIRCUIT .
STEP 4. Verify the central door locking system.
Check that the central door locking system works normally.

Q: Is the check result normal?
1. YES: Go to Step 5.
2. NO: Refer to TROUBLESHOOTING .

STEP 5. Using scan tool MB991958, check data list.

Check the signals related to the keyless entry system operation.

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

Connect scan tool MB991958. Refer to "HOW TO CONNECT THE SCAN TOOL (M.U.T.-III) ."
Turn the ignition switch to the "LOCK" (OFF) position.

Check the ETACS data list.

Close the driver's door.
Close the passenger's door.
Close the RH-side rear door.
Close the LH-side rear door.
Close the trunk lid.

Remove the ignition key from the ignition key cylinder.

ITEM REFERENCE

Item No.	Item name	Normal condition
Item 256	Dr door ajar switch	Close
Item 257	As door ajar switch	Close
Item 258	RR door ajar switch	Close
Item 259	RL door ajar switch	Close
Item 260	Trunk/gate trunk ajar switch	Close
Item 264	Handle lock switch	Key in → Key out

Fig 3: Connecting Scan Tool To Data Link Connector

Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

OK: Normal condition is displayed.

Q: Are the check results normal?

YES <Normal conditions are displayed for all the items.>: Go to Step 6.
NO <Normal condition is not displayed for item No. 256.>: Refer to INSPECTION PROCEDURE 5: ETACS-ECU DOES NOT RECEIVE ANY SIGNAL FROM THE FRONT DOOR SWITCH (LH) .
NO <Normal condition is not displayed for item No. 257.>: Refer to INSPECTION PROCEDURE 6: ETACS-ECU DOES NOT RECEIVE ANY SIGNAL FROM THE FRONT DOOR SWITCH (RH) .
NO <Normal condition is not displayed for item No. 258.>: Refer to INSPECTION PROCEDURE 8: ETACS-ECU DOES NOT RECEIVE ANY SIGNAL FROM THE REAR DOOR SWITCH (RH) .
NO <Normal condition is not displayed for item No. 260.>: Refer to INSPECTION PROCEDURE 9: ETACS-ECU DOES NOT RECEIVE ANY SIGNAL FROM THE TRUNK LID LATCH. .
NO <Normal condition is not displayed for item No. 264.>: Refer to INSPECTION PROCEDURE 3: ETACS-ECU DOES NOT RECEIVE ANY SIGNAL FROM THE KEY REMINDER SWITCH. .

STEP 6. Check receiver antenna assembly connector D-14 and WCM connector C-07 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
Q: Is the receiver antenna assembly connector D-14 and WCM connector C-07 in good condition?
1. YES: Go to Step 7.
2. NO: Repair the defective connector.
STEP 7. Check the wiring harness between the receiver antenna assembly connector D-14 (terminal Nos. 1, 3 and 5) and the WCM connector C-07 (terminal Nos. 1, 3 and 5) for open circuit.
1. Disconnect receiver antenna assembly connector D-14 and WCM connector C-07, and check the wiring harness.
2. Check the wiring harness between receiver antenna assembly connector D-14 (terminal No. 1) and WCM connector C-07 (terminal No. 1).
  OK: Continuity exists (2 Ω or less)
  
  Fig 4: Checking Wiring Harness Between Receiver Antenna Terminal 1 And WCM Terminal 1
  Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
3. Check the wiring harness between receiver antenna assembly connector D-14 (terminal No. 3) and WCM connector C-07 (terminal No. 3).
  OK: Continuity exists (2 Ω or less)
  
  Fig 5: Checking Wiring Harness Between Receiver Antenna Terminal 3 And WCM Terminal 3
  Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
4. Check the wiring harness between receiver antenna assembly connector D-14 (terminal No. 5) and WCM connector C-07 (terminal No. 5).
  OK: Continuity exists (2 Ω or less)
  
  Fig 6: Checking Wiring Harness Between Receiver Antenna Terminal 5 And WCM Terminal 5
  Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
  
  Q: Is the wiring harness between receiver antenna assembly connector D-14 (terminal Nos. 1, 3 and 5) and the WCM connector C-07 (terminal Nos. 1, 3 and 5) in good condition?
  1. YES: Go to Step 8.
  2. NO (receiver antenna assembly connector D-14 terminal No. 1 - WCM connector C-07 terminal No. 1.): Repair the wiring harness between receiver antenna assembly connector D-14 (terminal No. 1) and WCM connector C-07 (terminal No. 1).
  3. NO (receiver antenna assembly connector D-14 terminal No. 3 - WCM connector C-07 terminal No. 3.): Repair the wiring harness between receiver antenna assembly connector D-14 (terminal No. 3) and WCM connector C-07 (terminal No. 3).
  4. NO (receiver antenna assembly connector D-14 terminal No. 5 - WCM connector C-07 terminal No. 5.): Repair the wiring harness between receiver antenna assembly connector D-14 (terminal No. 5) and WCM connector C-07 (terminal No. 5).
STEP 8. Check the wiring harness between the receiver antenna assembly connector D-14 (terminal Nos. 1, 3 and 5) and the ground for short circuit.
1. Disconnect receiver antenna assembly connector D-14 and WCM connector C-07, and check the wiring harness.
2. Check the wiring harness between receiver antenna assembly connector D-14 (terminal No. 1) and ground
  OK: No continuity
  
  Fig 7: Checking Wiring Harness Between Receiver Antenna Assembly Connector D-14 Terminal 1 And Ground
  Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
3. Check the wiring harness between receiver antenna assembly connector D-14 (terminal No. 3) and ground
  OK: No continuity
  
  Fig 8: Checking Wiring Harness Between Receiver Antenna Assembly Connector D-14 Terminal 3 And Ground
  Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
4. Check the wiring harness between receiver antenna assembly connector D-14 (terminal No. 5) and ground
  OK: No continuity
  
  Fig 9: Checking Wiring Harness Between Receiver Antenna Assembly Connector D-14 Terminal 5 And Ground
  Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
  
  Q: Is the wiring harness between receiver antenna assembly connector D-14 (terminal Nos. 1, 3 and 5) and the ground in good condition?
  1. YES: Go to Step 9.
  2. NO (receiver antenna assembly connector D-14 terminal No. 1 - ground.): Repair the wiring harness between receiver antenna assembly connector D-14 (terminal No. 1) and the ground.
  3. NO (receiver antenna assembly connector D-14 terminal No. 3 - ground.): Repair the wiring harness between receiver antenna assembly connector D-14 (terminal No. 3) and the ground.
  4. NO (receiver antenna assembly connector D-14 terminal No. 5 - ground.): Repair the wiring harness between receiver antenna assembly connector D-14 (terminal No. 5) and the ground.
STEP 9. Retest the system.
Replace the receiver antenna assembly. Check if the keyless entry system works normally.

Q: Is the check result normal?
1. YES: Intermittent malfunction (Refer to HOW TO COPE WITH INTERMITTENT MALFUNCTION ).
2. NO: Replace WCM and register the ID codes (Refer to ID CODES REGISTRATION JUDGMENT TABLE ).