DTC B2353: Ignition Power Supply (Low Input); DTC B2354: Ignition Power Supply (High Input): Diagnosis

Required Special Tools: 

• MB991223: Harness Set
• MB992006: Extra Fine Probe
• MB991958 Scan Tool (M.U.T.-III Sub Assembly)
  • MB991824: Vehicle Communication Interface (V.C.I).
  • MB991827 M.U.T.-III USB Cable
  • MB991910 M.U.T.-III Main Harness A (Vehicles with CAN communication system)

1. STEP 1. Using scan tool MB991958, check data list. 

   Check the ignition power supply voltage.

   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 THE SCAN TOOL (M.U.T.-III)  ".
   2. Check the ETACS data list.
      • Turn the ignition switch to the "ON" position.
        ITEM CONDITION CHART
        
        

        Item No.	Item name	Normal condition
        Item 254	IG voltage	Approximately 12 volts (battery positive voltage)

   3. Turn the ignition switch to the "LOCK" (OFF) position.

   Q: Do the scan tool MB991958 display the item "IG voltage" is normal condition? 

   YES  : Go to  Step 7.

   NO  : Go to Step 2.

   Fig 1: Connecting Special Tool To Data Link Connector

   Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
2. STEP 2. Battery check 

   Refer to BATTERY TEST .

   Q: Is the battery in good condition? 

   YES  : Go to Step 3.

   NO  : Charge or replace the battery.

3. STEP 3. Charging system check 

   Refer to OUTPUT CURRENT TEST .

   Q: Is the charging system in good condition? 

   YES  : Go to Step 4.

   NO  : Repair or replace the charging system component(s).

4. STEP 4. Check ETACS-ECU connector C-317 for loose, corroded or damaged terminals, or terminals pushed back in the connector. 

   Q: Is ETACS-ECU connector C-317 in good condition? 

   YES  : Go to Step 5.

   NO  : Repair or replace the component(s). Refer to HARNESS CONNECTOR INSPECTION .

5. STEP 5. Check the ignition switch (IG1) circuit to the ETACS-ECU. Measure the voltage at ETACS-ECU connector C-317. 
   1. Disconnect ETACS-ECU connector C-317 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 6 and ground.
      • The voltage should measure approximately 12 volts (battery positive voltage).

   Q: Is the measured voltage approximately 12 volts (battery positive voltage)? 

   YES  : Go to  Step 7.

   NO  : Go to Step 6.

   Fig 2: Measuring Voltage At ETACS-ECU Connector C-317

   Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
6. STEP 6. Check the wiring harness between ETACS-ECU connector C-317 (terminal 6) and the ignition switch (IG1). 

   Check the power supply line for open circuit and short circuit.

   Q: Is the wiring harness between ETACS-ECU connector C-317 (terminal 6) and the ignition switch (IG1) in good condition? 

   YES  : No action is necessary and testing is complete.

   NO  : The wiring harness may be damaged or the connector(s) may have loose, corroded or damaged terminals, or terminals pushed back in the connector. Repair the wiring harness as necessary.

7. STEP 7. Recheck for diagnostic trouble. 

   Check again if the DTC is set to the ETACS-ECU.

   1. Erase the DTC.
   2. Turn the ignition switch from "LOCK" (OFF) position to "ON" position.
   3. Check if DTC is set.
   4. Turn the ignition switch to the "LOCK" (OFF) position.

   Q: Is the DTC set? 

   YES  : Replace the ETACS-ECU.

   NO  : The trouble can be an intermittent malfunction (Refer to HOW TO COPE WITH INTERMITTENT MALFUNCTION ).