The SBM uses information from other systems in order to execute certain functions. Before further diagnosis, refer to the general information on how the SBM operates and how each system interacts with the SBM. This will save diagnostic time, future misdiagnosis, and unnecessary parts replacement.

Use a scan tool in order to diagnose the SBM as referred to in diagnostic procedures. The scan tool can preform the following functions:

Become familiar with the SBM capabilities and diagnostic features. The self-diagnostic features are referenced in the DTC tables and are very useful in diagnosing non-DTC setting malfunctions as well.

Replace the SBM only if the diagnostic procedures direct you to do so. Every input to the SBM and every output from the SBM is ground/short to battery protected, so the SBM does not automatically need to be replaced when a short is found in the wiring. Repair the wiring first. Then inspect the system for further problems. Most system malfunctions are traceable to faulty wiring and connectors, and occasionally to components. The SBM is very reliable and not the likely cause of a system malfunction. Replacing the SBM before a complete diagnosis usually results in a recurrence of the original complaint malfunction.

The SBM stores DTCs as current as history codes. If the SBM detects a system malfunction, the SBM stores a DTC that corresponds to that particular malfunction. The SBM does not send a message to the IPC to display a message. If a current DTC stores and the fault is no longer present, some DTCs remain current until the first ignition cycle. Other DTCs become history when the fault is no longer present and does not require an ignition cycle. History DTCs are intermittent malfunctions and must be diagnosed differently than current DTCs. Refer to Intermittents and Poor Connections .

Use a scan tool in order to read DTCs.