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TuningBot DTC Database · v4.37.14

U0621 Lost Communication With Exhaust Gas Temperature Sensor Bank 2 Sensor 1

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

U · NetworkNetworkOBD2

What U0621 means

U0621
Lost Communication With Exhaust Gas Temperature Sensor Bank 2 Sensor 1 Generic · network Data confidence 65%

The control module stopped receiving expected network messages from the Exhaust Gas Temperature Sensor Bank 2 Sensor 1 node on the vehicle communication bus.

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

How to read U0621

U

Network: communication between control units.

0

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

621

Specific fault index within the subsystem.

Frequently asked questions about U0621

What does U0621 mean?

Lost Communication With Exhaust Gas Temperature Sensor Bank 2 Sensor 1. The control module stopped receiving expected network messages from the Exhaust Gas Temperature Sensor Bank 2 Sensor 1 node on the vehicle communication bus.

Is U0621 generic or manufacturer-specific?

U0621 is a generic OBD-II code: it has the same meaning on every make and model that follows the SAE standard.

Can TuningBot remove U0621 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 U0621 is removable in your case.

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