CP-A138
CP_a138_swcanCommsAcEvseFaulted
Also written as CP_A138 / CP A138 / CP_a138_swcanCommsAcEvseFaulted / cp_a138_swcancommsacevsefaulted
Why does the exact Tesla alert ID matter?
Record the exact alert ID, including underscores, suffixes, and companion alerts. Tesla alerts that look similar can point to different modules, timestamps, and service procedures.
What does CP-A138 mean?
Tesla alert code in the Charge Port (CP) module. AC EVSE communicating over SWCAN faults The EVSE reports it is faulted over SWCAN The EVSE reports via SWCAN that it is no longer faulted, or the cable is unplugged Charging may not start or may be interrupted unexpectedly. Latch calibration data is unavailable (Gen 1-2 only) EEPROM indicates that latch offset is not valid for more than one second EEPROM indicates that latch offset is valid Latch position may not be sensed correctly, latch may not engage or disengage The high voltage cover is not detected The high voltage cover is detected The CP has instigated a wake up event due to proximity Expected the cable to be latched in but latch is disengaged, may be frozen info from manualCP_A079 Charge port latch does not read engaged after being driven engaged and cold weather mode is active Charge port latch reads engaged Charge port latch may be frozen disengaged, AC charging rate may be limited and DC charging may not start
Original Description
AC EVSE communicating over SWCAN faults The EVSE reports it is faulted over SWCAN The EVSE reports via SWCAN that it is no longer faulted, or the cable is unplugged Charging may not start or may be interrupted unexpectedly. Latch calibration data is unavailable (Gen 1-2 only) EEPROM indicates that latch offset is not valid for more than one second EEPROM indicates that latch offset is valid Latch position may not be sensed correctly, latch may not engage or disengage The high voltage cover is not detected The high voltage cover is detected The CP has instigated a wake up event due to proximity Expected the cable to be latched in but latch is disengaged, may be frozen info from manualCP_A079 Charge port latch does not read engaged after being driven engaged and cold weather mode is active Charge port latch reads engaged Charge port latch may be frozen disengaged, AC charging rate may be limited and DC charging may not start
Affected Tesla Models
What You May Notice
- Charge port alert: AC EVSE communicating over SWCAN faults The EVSE reports it is faulted over SWCAN The EVSE reports via SWCAN that it is
- Charging session may be interrupted or not starting as expected
- Charge port light flashing amber or red
How to Diagnose and Resolve
- 1 Unplug and re-plug the charge cable
- 2 Try a different charging cable or Supercharger stall
- 3 Reboot the vehicle and attempt to charge again
- 4 If "AC EVSE communicating over SWCAN faults The EVSE r" persists, contact Tesla Roadside Assistance
- 5 Schedule a Service Center visit if the problem continues
Severity Notes
CP-A138 is an Alert in the Charge Port system. Confirm the vehicle screen and Tesla app show no driving or charging restrictions, and schedule service if the alert returns.