Those with a scan tool and/or OBD reader may be interested in this from OASIS: Jun 06 2014 5013 -Unexpected Scan Tool And/Or Vehicle Electronic Module Behavior During Diagnostics During diagnostics some vehicles may exhibit unexpected vehicle electronic module or IDS / scan tool behavior. For example, on-demand self test failure, missing Parameter Identification Data (PIDs) selections in data logger, and/or other IDS / scan tool functional concerns. This may be caused by excessively high or low battery voltage. Verify that vehicle battery voltage is no higher than 14.75 volts and no lower than 12 volts during diagnostics when using IDS / scan tool.