Inspection Procedure 3: Abnormality in KOS-ECU power supply and ground circuits: Diagnosis

WARNING: This page is about a different car, the 2008 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

STEP 1. Check KOS-ECU connector C-05 and ETACS-ECU connector C-317 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
Q: Is the KOS-ECU connector C-05 and ETACS-ECU connector C-317 in good condition?

YES : Go to Step 2.

NO : Repair the defective connector.
STEP 2. Check the wiring harness between the KOS-ECU connector C-05 (terminal No.38, 39) and the ETACS-ECU connector C-317 (terminal No.10, 5) for open circuit.
1. Disconnect KOS-ECU connector C-05 and ETACS-ECU connector C-317, and check the wiring harness.
2. Check the wiring harness between KOS-ECU connector C-05 (terminal No.38) and ETACS-ECU connector C-317 (terminal No.10)
  OK: Continuity exists (2 Ω or less)
  
  Fig 1: Checking Wiring Harness Between KOS-ECU Connector C-05 Terminal 38And ETACS-ECU Connector C-317 Terminal 10
  Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
3. Check the wiring harness between KOS-ECU connector C-05 (terminal No.39) and ETACS-ECU connector C-317 (terminal No.5)
  OK: Continuity exists (2 Ω or less)
  
  Fig 2: Checking Wiring Harness Between KOS-ECU Connector C-05 Terminal 39 And ETACS-ECU Connector C-317 Terminal 5
  Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
Q: Is the wiring harness between KOS-ECU connector C-05 (terminal No.38, 39) and the ETACS-ECU connector C-317 (terminal No.10, 5) in good condition?

YES : Go to Step 3.

NO : Repair the wiring harness between KOS-ECU connector C-05 (terminal No.38, 39) and the ETACS-ECU connector C-317 (terminal No.10, 5).
STEP 3. Check the wiring harness between the KOS-ECU connector C-05 (terminal No.38, 39) and the ground for short circuit.
1. Disconnect KOS-ECU connector C-05, and check the wiring harness.
2. Check the wiring harness between KOS-ECU connector C-05 (terminal No.38) and ground
  OK: No continuity
  
  Fig 3: Checking Wiring Harness Between KOS-ECU Connector C-05 Terminal 38 And Ground
  Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
3. Check the wiring harness between KOS-ECU connector C-05 (terminal No.39) and ground
  OK: No continuity
  
  Fig 4: Checking Wiring Harness Between KOS-ECU Connector C-05 Terminal 39 And Ground
  Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
Q: Is the wiring harness between KOS-ECU connector C-05 (terminal No.38, 39) and the ground in good condition?

YES : Go to Step 4.

NO : Repair the wiring harness between KOS-ECU connector C-05 (terminal No.38, 39) and the ground.
STEP 4. Check the wiring harness between the KOS-ECU connector C-05 and the ground for open circuit.
1. Disconnect KOS-ECU connector C-05, and check the wiring harness.
2. Check the wiring harness between KOS-ECU connector C-05 (terminal No.14) and ground.
  OK: Continuity exists (2 Ω or less)
  
  Fig 5: Checking Wiring Harness Between KOS-ECU Connector C-05 Terminal 14 And Ground
  Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
Q: Is the wiring harness between KOS-ECU connector C-05 and the ground in good condition?

YES : Go to Step 5.

NO : Repair the wiring harness between KOS-ECU connector C-07 and ground.
STEP 5. Retest the system
Q: Does the abnormality in KOS-ECU power supply and ground circuits in good condition?

YES : The trouble can be an intermittent malfunction (Refer to HOW TO COPE WITH INTERMITTENT MALFUNCTION ).

NO : Replace KOS-ECU and register the ID codes (Refer to ID CODE REGISTRATION NECESSITY JUDGMENT TABLE ).