INSPECTION PROCEDURE 5: When the TCL Switch is Push On, TCL System dose not Cancelled.: Diagnosis

WARNING: This page is about a different car, the 2004 Mitsubishi Galant. However, it is still accessible from the selected car via links, so may be relevant.

Required Special Tools:

MB991223: Harness set
MB991958: Scan tool (MUT-III sub assembly)
MB991824: V.C.I.
MB991827: MUT-III USB cable
MB991910: MUT-III main harness A
MB991970: ABS check harness

STEP 1. Measure the terminal voltage at ABS/TCL-ECU connector A-02.
1. Disconnect all the connectors from the ABS/TCL-ECU.
  
  Fig 1: Identifying ABS/TCL-ECU Connector A-02
  Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
2. Connect special tool MB991970 between the ABS/TCL-EUC and the body-side harness connector.
3. Turn the ignition switch to the "ON" position.
4. Measure the terminal voltage between special tool MB991970 connector terminal 6 (ABS/TCL-ECU connector A-02 terminal 6) and ground.
  - When the TCL switch is not pressed, the voltage should measure battery positive voltage (approximately 12 volts).
  - When the TCL switch is pressed, the voltage should measure 1 volt or less.
5. Turn the ignition switch to the "LOCK" (OFF) position.
6. Disconnect special tool MB991970 between the ABS/TCL-ECU and the body-side harness connector.
7. Connect all the connectors from the ABS/TCL-ECU.
  
  Fig 2: Measuring Voltage Between Special Tool And Ground
  Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
  
  Q: Is the terminal voltage battery terminal voltage when the TCL switch is not pressed, and is the terminal voltage 1 volt or less when the TCL switch is pressed?
  1. YES: Go to Step 6.
  2. NO: Go to Step 2.
STEP 2. Check the TCL switch.
1. Remove the TCL switch (Refer to TCL SWITCH ).
2. Connect an ohmmeter to the TCL switch between terminals 1 and 2.
3. Check the continuity between terminals 1 and 2 when the TCL switch is operated.
  - There is no continuity between terminals 1 and 2 when the TCL switch is not pressed.
  - There is continuity between terminals 1 and 2 when the TCL switch is pressed.
    
    Fig 3: Checking Continuity Between TCL Switch Terminals 1 And 2
    Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    
    Q: Is there no continuity between terminals 1 and 2 when the TCL switch is not pressed, and is there continuity when the TCL switch is pressed?
    1. YES: Install the TCL switch (Refer to TCL SWITCH ). Then go to Step 6.
    2. NO: Replace the TCL switch (Refer to TCL SWITCH ). Then go to Step 7.
STEP 3. Check ABS/TCL-ECU connector A-02, intermediate connector C-29 and TCL switch connectors C-131 for loose, corroded or damaged terminals, or terminals pushed back in the connector.

Fig 4: Identifying Connector A-02
Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

Fig 5: Identifying Connectors C-29 & C-131
Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

Q: Are there connectors and terminals in good condition?
1. YES: Go to Step 4.
2. NO: Repair or replace the faulty connector (Refer to HARNESS CONNECTOR INSPECTION ). Then go to Step 7.
STEP 4. Check the harness wire between ABS/TCL-ECU connector A-02 terminal 6 and TCL switch connector C-131 terminal 1 for damage.

Fig 6: Identifying ABS/TCL-ECU Connector A-02
Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

Fig 7: Identifying TCL Switch Connector C-131
Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

Q: Are there harness wires in good condition?
1. YES: Go to Step 5.
2. NO: Repair the damaged harness wire. Then go to Step 7.
STEP 5. Check the harness wire between TCL switch connector C-131 terminal 2 and ground for damage.

Fig 8: Identifying TCL Switch Connector C-131
Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

Fig 9: Identifying Ground
Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

Q: Is the harness wire in good condition?
1. YES: Go to Step 6.
2. NO: Repair the damaged harness wire. Then go to Step 7.
STEP 6. Retest the system
Q: Dose TCL system cancelled, when the TCL switch is push on?
1. YES: It can be assumed that this malfunction is intermittent (Refer to HOW TO COPE WITH INTERMITTENT MALFUNCTIONS ).
2. NO: Replace the hydraulic unit (integrated with ABS/TCL-ECU) (Refer to HYDRAULIC UNIT ). Then go to Step 7.
STEP 7. Retest the system
Q: Dose TCL system cancelled, when the TCL switch is push on?
1. YES: The procedure is complete.
2. NO: Return to Step 1.