On-Board Diagnostics

DIAGNOSIS FUNCTION

ON-BOARD DIAGNOSTICS

The multi-center display displays input/output signals (some signals all the time and others under specified conditions). When an irregular signal is initially monitored, the multi-center display decides that a malfunction has occurred and records the occurrence as a diagnostic trouble code. There are 9 diagnostic items. The diagnostic results can be read with a scan tool MB991958 (M.U.T.-III sub assembly). Diagnostic trouble codes are kept in memory by direct battery feed. The codes are retained in memory even if the ignition switch is in the "LOCK" (OFF) position. Diagnostic trouble codes will, however, be erased when a battery terminal or the multi-center display connector is disconnected. In addition, the diagnostic trouble code can also be erased by scan tool MB991958 (M.U.T.-III sub assembly).
NOTE:
If a connector or sensor is disconnected when the ignition switch is in the "ON" position, a diagnostic trouble code is stored in memory. In this case, erase the DTC using the scan tool.

NOTE:
The 9 diagnostic items are displayed in numeric order.