C2100

DTC C2100: Battery Voltage Malfunction (Low Voltage)

















CAUTION
^ If there is any problem in the CAN bus lines, an incorrect diagnostic trouble code may be set. Prior to this diagnosis, diagnose the CAN bus lines.
^ Whenever the ECU is replaced, ensure that the CAN bus lines are normal.

OPERATION
AWC-ECU power supply is provided from the battery via ETACS-ECU.

DTC SET CONDITIONS
This diagnostic trouble code is set when the abnormality below is detected:
^ When the AWC-ECU power supply voltage and solenoid valve power supply voltage are 9 V or less.
^ When ASC-ECU low voltage is detected.

PROBABLE CAUSES
^ Malfunction of ASC-ECU
^ Malfunction of the ETACS-ECU
^ Defective battery
^ Charging system failed
^ Damaged harness wires and connectors
^ Malfunction of AWC-ECU

DIAGNOSTIC PROCEDURE

STEP 1. Scan tool CAN bus diagnostics
Using scan tool MB991958, diagnose the CAN bus lines.
Q: Is the check result normal?
YES: Go to Step 3.
NO: Repair the CAN bus lines. After repairing the CAN bus line, go to Step 2.

STEP 2. Check whether the DTC is reset.
Q: Is DTC No. C2100 set?
YES: Go to Step 3.
NO: This diagnosis is complete.

STEP 3. Scan tool diagnostic trouble code
Check the ASC diagnostic trouble code. Diagnostic Trouble Code Descriptions
Q: Is the DTC set?
YES: Perform the relevant troubleshooting.
NO: Go to Step 4.

STEP 4. Scan tool diagnostic trouble code
Check the ETACS diagnostic trouble code. (Diagnostic Trouble Code Descriptions)
Q: Is the DTC set?
YES: Perform the relevant troubleshooting.
NO: Go to Step 5.

STEP 5. Check the battery.
Battery Test.
Q: Is the check result normal?
YES: Go to Step 7.
NO: Charge or replace the battery. Then go to Step 6.

STEP 6. Check the charging system.
Generator Output Line Voltage Drop Test
Q: Is the check result normal?
YES: Go to Step 7.
NO: Repair or replace the charging system component(s).

STEP 7. Voltage measurement at C-46 AWC-ECU connector
Measure the voltage between C-46 AWC-ECU connector terminal No. 12 - and the body ground.
OK: Battery positive voltage
Q: Is the check result normal?
YES: Go to Step 11.
NO: Go to Step 8.

STEP 8. AWC-ECU connector, ETACS-ECU connector check: C-46, C-315
Q: Is the check result normal?
YES: Go to Step 9.
NO: Repair the defective connector. Then go to Step 14.

STEP 9. Check the wiring harness between C-46 AWC-ECU connector terminal No. 12 and C-315 ETACS-ECU connector terminal No.4.
Check the wiring harness for open or short circuit (short to ground).
Q: Is the check result normal?
YES: Go to Step 10.
NO: Check C-41 intermediate connector, C-43 J/C (4), C-103 J/C (3). When no problem is found, repair the wiring harness. Then go to Step 14.

STEP 10. Scan tool service data
Item No. 43: Battery voltage (Data List Reference Table)
Q: Is the check result normal?
YES: Intermittent malfunction.
NO: Replace the ETACS-ECU. Then go to Step 14.

STEP 11. AWC-ECU connector check: C-46
Q: Is the check result normal?
YES: Go to Step 12.
NO: Repair the defective connector. Then go to Step 14.

STEP 12. Check the wiring harness between C-46 AWC-ECU connector terminal No. 13 and body ground.
Check the wiring harness for open circuit.
Q: Is the check result normal?
YES: Go to Step 13.
NO: Repair the wiring harness. Then go to Step 14.

STEP 13. Scan tool service data
Item No. 43: Battery voltage (Data List Reference Table)
Q: Is the check result normal?
YES: Intermittent malfunction.
NO: Replace the AWC-ECU. Then go to Step 14.

STEP 14. Check whether the DTC is reset.
Q: Is DTC No. C2100 set?
YES: Return to Step 1.
NO: This diagnosis is complete.