Inspection Procedure N-6: Column Switch: The ETACS-Ecu Does Not Receive Any Signal From The Taillight Switch, The Headlight Switch, The Passing Light Switch, The Dimmer Switch Or The Turn-Signal Light Switch.: Diagnosis

Required Special Tools: 

• MB991223: Harness Set
• MB991958: Scan Tool (MUT-III Sub Assembly)
  • MB991824: Vehicle Communication Interface (V.C.I.)
  • MB991827: MUT-III USB Cable
  • MB991911: MUT-III Main Harness B
• MB991813: SWS monitor kit
  • MB991806: SWS monitor cartridge
  • MB991812: SWS monitor harness (for column-ECU)
  • MB991922: Probe harness

1. STEP 1. Use scan tool MB991958 to select "ECU COMM Check" on the SWS monitor display. 

   Check the column-ECU.

   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 special tool MB991911 before connecting special tool MB991812. Be sure to connect special tool MB991806 after turning on special tool MB991824.
   1. Connect the special tool. Refer to "HOW TO CONNECT SWS MONITOR ."
   2. Turn the ignition switch to the "LOCK" (OFF) position.
   3. Operate scan tool MB991958 according to the procedure below to display "ECU COMM Check."
      1. Select "Interactive Diagnosis."
      2. Select "System select."
      3. Select "SWS."
      4. Select "SWS MONITOR."
      5. Select "ECU COMM Check."
   4. Scan tool MB991958 should show "OK" on the "ECU COMM Check" menu for the "COLUMN ECU" menu.

   Q: Is "OK" displayed on the "COLUMN ECU" menu? 

   • YES :  Go to Step 2.
   • NO :  Refer to "INSPECTION PROCEDURE A-2: COMMUNICATION WITH THE COLUMN SWITCH (COLUMN-ECU) IS NOT POSSIBLE ."
   Fig 1: Connecting Special Tool MB991911 To Data Link Connector

   Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
2. STEP 2. Replace the column switch. 
   1. Replace the column switch.
   2. If the functions described in "CIRCUIT OPERATION" work normally, the input signal from the column switch (turn-signal light and lighting switch) should be normal.

   Q: Does the column switch (turn-signal light and lighting switch) send normal signal to the ECU? 

   • YES :  No action is necessary and testing is complete.
   • NO :  Replace the ETACS-ECU. If the functions described in "CIRCUIT OPERATION" work normally, the input signal from the column switch (turn-signal light and lighting switch) should be normal.