R-Pro › Field cases › Transport refrigeration
Engine-to-Standby Auto Transfer Failure (ATS Fault)
Likely causes
ATS contact carbonized or worn
Check: Visually inspect ATS contacts — check for carbonization and discoloration; verify STANDBY display when shore power connected
What to do: Polish contacts or replace ATS unit → clean shore power plug and remove oxidation → re-test ATS transfer
ATS control coil open circuit — transfer operation impossible
Check: Measure ATS control coil resistance: typically 100–300Ω per manufacturer nameplate — outside range indicates faulty coil
What to do: Replace ATS coil/unit → after replacement, verify STANDBY display and transfer operation when shore power connected
Shore power frequency mismatch (50Hz/60Hz) or voltage detection threshold not configured
Check: Check shore power detection voltage threshold in controller service menu → verify 50Hz/60Hz selection setting
What to do: Set 50Hz/60Hz selection to match local power supply → reconfigure shore power detection threshold → re-test ATS transfer
ATS diagnostic: no STANDBY display after connecting shore power = ATS input detection fault; STANDBY shown but no transfer = ATS contact/coil fault — diagnose in two steps.
All 565 cases work offline in R-Pro, with error codes for 62 brands and P-T data for 108 refrigerants.
Open R-Pro →Related cases
- Reefer Truck Fails to Reach Setpoint During Driving
- Temperature Variation Inside Cargo Box — Uneven Cooling by Zone
- Poor Temperature Recovery After Door Opening
- Temperature Rise During Engine-Stop Standby Mode Switch
- Multi-Temperature Cargo Box Zone Failure — Partition Fault
- Diesel Engine Fails to Start or Shuts Down Prematurely