PWT bus acknowledgement test not performed.
â–¶ How to fix
Check the wiring and connectors on TMS (E5) and EMS (E44). Check if EMS has any DTCs and troubleshoot those. If any software upgrade is available for the EMS or the TMS, proceed with the upgrade. If none of the above helps replace EMS and ultimately replace TMS.
What you'll see
System can not guarantee a end to end protected communication between TMS (E5) and EMS (E44)
System reaction
Yellow warning lamp
Diagnostic depth
Detection
ECU indicating that acknowledgment test can not be performed.
Possible cause
ECU is considering EMS not to be awake.