ASC
DTC C2100: Abnormality in battery voltage (low voltage)Solenoid Valve and Motor Power Supply Circuit:
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.
CIRCUIT OPERATION
^ The ASC-ECU is energized by the valve power supply circuit (terminal No. 26).
^ When the power is supplied from the ignition switch (IG1) to the IG1 relay in ETACS-ECU, IG1 relay is turned on. At this time, the valve power supply circuit (terminal No. 26) energizes the ASC-ECU.
DTC SET CONDITIONS
This diagnostic trouble code is set in the following case.
^ When the ASC-ECU power supply voltage drops below 9.7 ± 0.3 volts during driving
^ When the ASC-ECU power supply voltage drops below 8.0 ± 0.5 volts during driving
PROBABLE CAUSES
^ Battery failure
^ Battery terminal looseness
^ Charging system failed
^ Damaged wiring harness and connectors
^ ASC-ECU malfunction
^ Fusible link malfunction
DIAGNOSIS
Required Special Tools:
^ 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
^ MB991997: ASC check harness
STEP 1. M.U.T.-III CAN bus diagnostics
Use scan tool to diagnose the CAN bus lines.
Q: Is the check result normal?
YES: Go to Step 3.
NO: Repair the CAN bus lines. On completion, go to Step 2.
STEP 2. Diagnostic Trouble code recheck after resetting CAN bus lines
Q: Is DTC C2100 set?
YES: Go to Step 3.
NO: The procedure is complete.
STEP 3. Fusible link check: Check the fusible link No. 27.
Visually check for open circuit in the fusible link No. 27.
Q: Is the check result normal?
YES: Go to Step 4.
NO: Replace the fusible link No.27.
STEP 4. Battery check
Q: Is the battery in good condition?
YES: Go to Step 5.
NO: Charge or replace the battery.
STEP 5. Charging system check
Q: Is the charging system in good condition?
YES: Go to Step 6.
NO: Repair or replace the charging system component(s).
STEP 6. Voltage measurement at the A-02 ASC-ECU connector
(1) Disconnect the connector, connect special tool MB991997 to the harness-side connector, and measure the voltage at the special tool connector side.
NOTE: Do not connect the special tool MB991997 to ASC-ECU.
(2) Turn the ignition switch to the ON position.
(3) Measure the voltage between the terminal No. 32 and the body ground.
OK: 12 volts (Battery voltage)
Q: Is the check result normal?
YES: Go to Step 8.
NO: Go to Step 7.
STEP 7. Connector check: A-02 ASC-ECU connector
Q: Is the check result normal?
YES: The open or short circuit may be present in the power supply circuit. Repair the wiring harness between the A-02 ASC-ECU connector terminal No. 32 and the fusible link No. 27.
NO: Repair the defective connector.
STEP 8. Resistance measurement at A-02 ASC-ECU connector
(1) Disconnect the connector, connect special tool MB991997 to the harness-side connector, and measure the voltage at the special tool connector side.
NOTE: Do not connect the special tool MB991997 to ASC-ECU.
(2) Resistance between the terminal No. 16 and the body ground
OK: Continuity exists (2 ohms or less)
Q: Is the check result normal?
YES: Go to Step 10.
NO: Go to Step 9.
STEP 9. Connector check: A-02 ASC-ECU connector
Q: Is the check result normal?
YES: An open circuit may be present in the ground circuit. Repair the wiring harness between the A-02 ASC-ECU connector terminal No. 16 and the body ground.
NO: Repair the defective connector.
STEP 10. Check whether the diagnostic Trouble code is reset.
Q: Is DTC C2100 set?
YES: Replace the ASC-ECU.
NO: Intermittent malfunction.