U1021: SCP (J1850) Invalid or Missing Data for Air Conditioning Clutch
LowNetwork/CommunicationNetwork Communication
What does U1021 mean?
U1021 is a diagnostic trouble code indicating "SCP (J1850) Invalid or Missing Data for Air Conditioning Clutch". This code relates to your vehicle's network communication and should be diagnosed to determine the root cause. The severity level helps indicate how urgently this should be addressed.
Common causes
- Faulty network communication component
- Wiring or connector issue in the related circuit
- Failed sensor providing incorrect readings
- Software/calibration issue requiring ECU update
- Related component causing secondary fault
What should you do?
This is a minor or informational code. Monitor for any changes in vehicle behaviour and address it during your next scheduled service visit.
Get a diagnosis for YOUR car
Code U1021 can mean different things depending on your vehicle. TorqueBot gives you a diagnosis specific to your make, model, and year.