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TuningBot DTC Database · v4.37.15

U040A Invalid Data Received From Air Conditioning Control Module

Generic (OBD-II) interpretation in the TuningBot DTC database.

U · NetworkNetworkOBD2

What U040A means

U040A
Invalid Data Received From Air Conditioning Control Module Generic · network Data confidence 65%

The control module registered the fault condition described as "Invalid Data Received From Air Conditioning Control Module".

Symptoms

  • Multiple warning lamps possible
  • Functions of the affected module unavailable

Possible causes

  • CAN bus wiring fault (open, short, chafed harness)
  • Faulty control module loading the bus
  • Connector or terminal corrosion
  • Power supply or ground fault of a module

Recommended checks

  • Perform a full-module scan to map which modules communicate
  • Check CAN bus resistance and voltages at the diagnostic connector
  • Inspect wiring and connectors of the affected module
  • Check module power supply and grounds
  • Disconnect suspect modules one at a time only with a documented procedure

Related and nearby codes

U04 range
U0400U0401U0402U0403U0404U0405U0406U0407U0408U0409U040BU040CU040DU040EU040FU0410U0411U0412

How to read U040A

U

Network: communication between control units.

0

Generic SAE-standard code: same meaning on every make.

40A

Specific fault index within the subsystem.

Frequently asked questions about U040A

What does U040A mean?

Invalid Data Received From Air Conditioning Control Module. The control module registered the fault condition described as "Invalid Data Received From Air Conditioning Control Module".

Is U040A generic or manufacturer-specific?

U040A is a generic OBD-II code: it has the same meaning on every make and model that follows the SAE standard.

Can TuningBot remove U040A at file level?

Not guaranteed. Powertrain (P) codes can be reliably disabled in the ECU calibration, but body, chassis and network codes depend on the specific control unit and how the fault is implemented - some can be handled, some cannot. Ask for a quote and our engineers will check your file and tell you, free of charge, whether U040A is removable in your case.

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