Diagnostic Item 11

DIAGNOSTIC ITEM 11: Diagnose when the scan tool cannot receive the data sent by TCL/ASC-ECU.

CAUTION: When servicing a CAN bus line, ground yourself by touching a metal object such as an unpainted water pipe. If you fail to do so, a component connected to the CAN bus line may be damaged.

FUNCTION
The diagnostic result demonstrates that "the scan tool cannot receive the sent data from TCL/ASC-ECU" when the scan tool MB991958 checks the periodically sent data from each ECU and cannot receive TCL/ASC-ECU data only.

TROUBLE JUDGEMENT CONDITIONS
Scan tool MB991958 judges the trouble when the periodically sent data from TCL/ASC-ECU cannot be received and sent.

TROUBLESHOOTING HINTS
- The wiring harness may be defective [open circuit between TCL/ASC-ECU and joint connector (3)]
- The connector may be defective [poor connection of joint connector (3) or TCL/ASC-ECU connector]
- Power supply circuit malfunction of TCL/ASC-ECU
- The TCL/ASC-ECU may be defective (internal open circuit)
- The TCL/ASC-ECU may be defective

DIAGNOSIS

- Diagnose the ASC system. Refer to TCL/ASC Diagnosis - Symptom procedures, TCL/ASC-ECU power supply circuit system. Inspection Procedure 3: TCL/ASC-ECU Power Supply Circuit System