Check UL1 Circuit

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

Possible causes

Defective UL1 solenoid coil
Damaged control relay
Exposed or broken wires
Microprocessor port failure

Recommended actions

Measure UL1 coil resistance
Check solenoid with test magnet
Inspect harness near compressor
Verify operation in diagnostic mode

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