Circuit/System Testing
WARNING: This page is about a different car, the 2008 GMC Yukon and 2008 Chevrolet Tahoe. However, it is still accessible from the selected car via links, so may be relevant.
- Verify no HPCM or ECM DTCs are set. Repair any HPCM or ECM DTCs prior to performing this diagnostic procedure.
- Engine at idle, observe the HPCM Autostop Inhibit Reasons and Hybrid Batt Max Cell Temp scan tool parameters.
- Compare the parameter display to the Typical Scan Tool Data information.
- Identify which Autostop inhibit conditions have prohibited Autostop operation. An Inhibit condition will display YES on the scan tool.
- Determine if the Autostop inhibit conditions are the result of normal operating conditions or the result of a fault condition.
- Repair the conditions that are the result of a fault condition. For example, a hood switch that indicates hood status as open when the hood is actually closed.
- Advise the vehicle operator of the normal operating conditions that will normally inhibit Autostop. For example, advise that Autostop is disabled when Hybrid Battery temperature is less than 10°C (50°F).