The D-Bug12XZ firmware combined with the Freescale LFBDMPGMR BDM programmer hardware provides a powerful low-level debugging environment for S12 and S12X MagniV devices. There are times when Electronic Control Modules (ECM) in a car will become inoperative or unresponsive to normal communication channels such as CAN or LIN. The Background Debug Module (BDM) on these devices combined with the D-Bug12XZ debugger provides the ability to reliably ‘hot-connect’ to the S12 and S12X MagniV devices without resetting or disturbing the running target. Once BDM communications is established with the target, the MCU’s I/O and memory resources can be uploaded for analysis. This session will teach the features and use of these tools to ‘hot connect’ to an unresponsive target MCU with the goal of determining the possible cause of the software and/or hardware failure.