Park Assist Control Module Falls Off CAN Bus

The Park Assist Control Module (PACM) may fall off the Controller Area Network (CAN) bus when other control modules are serviced on some 2020 CT5 models due to incorrect PACM software operation.

When some control modules are serviced — unplugging the Electronic Brake Control Module, for example — it breaks the CAN lines and the PACM does not recover until a power reset/fuse removal takes place. As a result, the PACM completely falls off the bus and no longer communicates. When this occurs, GDS 2 cannot be used to communicate or key provision the PACM.

The PACM uses the ultrasonic object sensors located in the fascias to provide distance measurements to nearby objects. (Fig. 20) The K182 PACM communicates with the K124 Image Processing Module on CAN 1.

To recover the PACM, cycle the PACM fuse or perform a battery disconnect.


Fig. 20


Refer to #PIC6393 for additional information.


– Thanks to Dave Antal

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