Electrical Faults (Voltage, Battery, Wiring)

Alarm 10 – Supply Air Temperature Sensor (SATS) Out of Range

Carrier Transicold alarm AL10 (Alarm Code 10) means the Advance microprocessor has detected the Supply Air Temperature Sensor (SATS/STS) reading is out of range, open, or shorted. The SATS lives in the discharge airstream after the evaporator on Vector, X4, X2 and Supra reefer units and is the primary control sensor when 'Supply' is selected. When AL10 latches, the controller falls back to the Return Air Sensor and box temperature control becomes unstable — a frequent cause of load-quality claims.

High A/C Amps

High electrical current detected in AC system components.

Battery Voltage Too High

The system detects a battery voltage exceeding 15.5V DC.

Battery Voltage Too Low

Battery voltage is below 10V DC during operation.

A/C Current Over Limit

AC current consumption exceeded pre-set limits.

Failed To Start – Auto Mode

Engine failed to start after maximum allowed automatic attempts.

Failed To Start – Manual

Failure to start the unit in manual mode.

Engine Failed to Stop

The engine does not shut down when the controller sends the signal.

Check Starter Circuit

Anomaly detected in the starter motor electrical circuit.

Check Engine RPM

The engine is not reaching or maintaining the required RPM for the operating cycle.

Check Engine Preheat Circuit

A problem has been detected in the preheat circuit (glow plugs), making cold starting difficult.

Alternator (Battery Charger) Not Charging

The alternator is not charging the unit's battery while the engine is running.

Check Remote Switch 1

Fail in the remote switch 1 circuit, usually related to door sensors or auxiliary switches.

Check Remote Switch 2

Failure in the remote switch 2 circuit, typically tied to a door sensor or auxiliary input. Close all compartment doors; if the unit remains shut down, repair immediately.

Datalogger Time Wrong

The internal data logger time and date do not match the current actual time.

Door Open

The sensor indicates a compartment door is open, stopping the unit.

Bad F2 or F3 Fuse

Failure in fuses F2 or F3 which control vital accessory power circuits.

Bad F4 or F6 Fuse

Failure detected in fuses F4 or F6, affecting control or lighting circuits.

AC Phase Reversed

External AC power phase is reversed, which can damage motors.

Compressor Motor Overload

The compressor motor overload relay has tripped due to excessive current.

Evap Motor Overheated

The evaporator fan motor is operating above its safe temperature threshold.

Check SV1 Circuit

Failure detected in the SV1 solenoid valve electrical circuit.

Check SV4 Circuit

Failure detected in the SV4 solenoid valve electrical circuit.

Check SV3 Circuit

Failure detected in the SV3 solenoid valve electrical circuit.

Check FHR Circuit

Failure in the Fuel Heater Relay (FHR) or heater circuit.

Check Remote Out of Range Light

The microprocessor detects an issue with the remote "Out of Range" indicator light.

Check Remote Defrost Light

Electrical issue detected in the remote Defrost indicator light circuit.

Check UL1 Circuit

Electrical failure detected in the Compressor Unloader 1 (UL1) circuit.

Check UL2 Circuit

Electrical failure detected in the Compressor Unloader 2 (UL2) circuit.

Check Remote Heat Light

The system reports a circuit problem with the remote heat indicator light.

Check Remote Cool Light

A problem has been detected in the remote cooling indicator light (Cool Light) circuit.

Check Remote Auto Light

Failure detected in the remote automatic mode light circuit (Auto Light).

Check AFA Solenoid Circuit

Problem in the air purifier solenoid circuit (AFA Solenoid).

Check 1HTCON1 Relay Coil

Failure in the 1HTCON1 relay coil (Heating Contactor 1).

Check 1HTCON2 Relay Coil

Failure in the 1HTCON2 relay coil (Heating Contactor 2).

Check Start Up Buzzer

Failure in the pre-start safety buzzer.

Check Comp Contactor 1

Error in compressor contactor 1.

Check CDCON Relay Coil

Failure in the CDCON relay coil (Condenser Fan).

Check GENCONR Relay Coil

Failure in the GENCONR relay coil (Generator Contactor).

Check SV2 Circuit

Issue detected in the SV2 (Hot Gas) solenoid valve circuit.

Check Standby Contactor

Failure in the electric standby mode contactor coil or circuit.

Check 2HTCON1 Relay Coil

Failure in the 2HTCON1 relay coil (Compartment 2 Heat 1).

Check 2HTCON2 Relay Coil

Failure in the 2HTCON2 relay coil (Compartment 2 Heat 2).

Check 3HTCON1 Relay Coil

Failure in the 3HTCON1 relay coil (Compartment 3 Heat 1).

Check 3HTCON2 Relay Coil

Failure in the 3HTCON2 relay coil (Compartment 3 Heat 2).

Check 2LSV Circuit

Issue in the Liquid Line Solenoid Valve 2 (2LSV) circuit.

Check 3LSV Circuit

Issue in the Liquid Line Solenoid Valve 3 (3LSV) circuit.

Check 1EVCON Relay Coil

Fault in the evaporator motor contactor 1 (1EVCON).

Check 2EVCON Relay Coil

Fault in the evaporator motor contactor 2 (2EVCON).

Check 3EVCON Relay Coil

Fault in the evaporator motor contactor 3 (3EVCON).

Check Economizer Circuit

Failure in the economizer circuit.

Check DCR2 Circuit

Fault in the DCR2 relay (Data Control Relay) circuit.

Check Return Air Sensor

Failure in the return air temperature sensor.

Check Supply Air Sensor

Fault detected on the supply air temperature sensor (SAS). If the unit shut down, repair immediately; otherwise report and repair at end of trip.

Check Defrost Termination 1 Sensor

Defrost termination sensor 1 detects an out-of-range or open circuit condition.

Check Suction Temp Sensor

Failure in the suction temperature sensor circuit.

Low/Unbalanced A/C Amps

Low or unbalanced AC current amperage detected at the generator.

Check Engine RPM Sensor

Signal loss or incorrect reading from the diesel engine RPM sensor.

Check Evap Temp Sensor

Failure detected in the evaporator coil temperature sensor.

Check Remote Temp Sensor 1

Signal error in remote temperature sensor number 1.

Check Remote Temp Sensor 2

Signal error in remote temperature sensor number 2.

C2 Check Supply Air Sensor

Supply air sensor error for compartment 2 (C2).

C3 Check Return Air Sensor

Return air sensor error for compartment 3 (C3).

C2 Check Defrost Sensor

Defrost sensor error for compartment 2 (C2).

Check Clutch Circuit

Compressor clutch circuit failure detected during Pretrip.

Check Speed Sol Circ

Failure in the engine speed solenoid circuit (high/low).

C2 Check Heater 1 Circuit

Failure in compartment 2 (C2) heater 1 circuit.

C2 Check Heater 2 Circuit

Failure in compartment 2 (C2) heater 2 circuit.

Check SV3 Circuit

Failure in solenoid valve 3 (SV3) circuit.

Check Eng Preheat Enable Circuit

Failure in the engine preheat enable circuit.

Check Fuel Solenoid Circuit

Failure detected in the fuel solenoid circuit (Run/Stop).

Check Return Air Sensor

Critical error in the return air sensor during Pretrip.

Check Supply Air Sensor

Critical error in the supply air sensor during Pretrip.

Check Coolant Temp Sensor

Engine coolant temperature sensor failure detected during Pretrip.

Check Bypass Circuit

Failure detected in the bypass valve circuit or operation.

Check Battery Current

Battery current reading is outside expected parameters during testing.

Check Ambient Air Sensor

Ambient air temperature sensor reports erratic values or is disconnected.

Check Suction Temp Sensor

Compressor suction temperature sensor is not responding correctly.

C3 Check Heater 1 Circuit

Failure in heating circuit 1 for compartment 3.

C2 Chk Supply Air Sensor

Failure in the compartment 2 supply air sensor.

C3 Check Heater 2 Circuit

Failure in the compartment 3 heating circuit 2.

Check LIV Circuit

Failure in the liquid injection valve (LIV) circuit.

Check UL1

Circuit failure for cylinder unloader number 1 (UL1).

Check Suction Mod Valve

Failure in the Suction Modulation Valve (SMV).

Check SV4 Valve

Failure in the circuit of solenoid valve SV4 (Hot Gas/Bypass Valve).

Check SV1 Valve

Failure in the solenoid valve SV1 circuit.

Check SV3 Valve

Failure in the solenoid valve SV3 circuit.

C2 Check Evap Fan Motor

Fault detected in the compartment 2 evaporator fan motor.

C3 Check Evap Fan Motor

Fault detected during Pretrip in the compartment 3 evaporator fan motor.

Check Evap Outlet Temp

The evaporator outlet temperature sensor does not respond correctly during tests.

Check Heater 1 Circuit

A fault was detected in the Heater 1 electrical circuit during Pretrip.

Check Heater 2 Circuit

Fault detected in the Heater 2 circuit, preventing effective defrost or heating.

Check Evap Fan Motor

General evaporator fan motor error detected during self-inspection.

Check Condenser Fan Motor

Fault in the condenser fan motor, compromising heat dissipation.

Check SV2 Circuit

Fault detected in the SV2 solenoid valve circuit.

Check Clutch

Failure in the coupling or electromagnetic clutch of the compressor.

Check Defrost Term 2 Sensor

Failure in the evaporator 2 defrost termination sensor.

Check Condenser Fan Circuit

Error in the control or power circuit of the condenser fans.

Check Comp Contact Circuit

Failure detected in the compressor contactor circuit (electric/standby mode).

Check Generator Cont Circ

Failure in the generator contactor circuit.

Check Standby Cont Circuit

Failure detected in the emergency power or standby circuit.

C3 Chk Return Air Sensor

Failure in the return air sensor for compartment 3.

Check Damper CR2 Circuit

Failure detected in the damper relay circuit CR2.

Check Damper CR1 Circuit

Failure in the control circuit for damper CR1.

Check Damper – Not Closing

The defrost damper does not close properly, preventing proper airflow during refrigeration.

Econo Calibrate Error

Error detected in the economizer sensor calibration.

Can Not Save Setting

The microprocessor cannot save changes made to settings or parameters.

Microprocessor Error

Generic internal microprocessor error; self-diagnostic failure.

Rear Panel Shutdown Requested

Unit shutdown requested from the rear or remote control panel.

Display Module Error

Communication failure or internal error in the display module.

Check Clutch Slip

Detection of clutch slip; loss of power transfer.

Check Remote Switch 3

Failure or abnormal status detected in auxiliary remote switch 3.

Fuel Pump Relay

Fault detected in the fuel pump relay circuit.

Diesel / Electric Relay

Problem with the relay that selects between Diesel and Electric (Standby) mode.

Bad F13 Fuse

Open or defective F13 fuse; generally affects auxiliary circuits.

Bad F9 Fuse

Open F9 fuse; this fuse typically protects control circuits.

Bad F5 Fuse

Blown F5 fuse; critical for safe system operation.

Bad F3 Fuse

Open F3 fuse; affects vital control logic components.

Bad F10 Fuse

Blown F10 fuse; interrupts critical control functions.

Check Standby Contactor 1

Failure in the electric mode (Standby) contactor number 1.