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TuningBot DTC Database · v4.37.14

U0636 Lost Communication With Hybrid/EV Battery Pack Coolant Control Valve A

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

U · NetworkNetworkOBD2

What U0636 means

U0636
Lost Communication With Hybrid/EV Battery Pack Coolant Control Valve A Generic · network Data confidence 65%

The control module stopped receiving expected network messages from the Hybrid/EV Battery Pack Coolant Control Valve A 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 U0636

U

Network: communication between control units.

0

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

636

Specific fault index within the subsystem.

Frequently asked questions about U0636

What does U0636 mean?

Lost Communication With Hybrid/EV Battery Pack Coolant Control Valve A. The control module stopped receiving expected network messages from the Hybrid/EV Battery Pack Coolant Control Valve A node on the vehicle communication bus.

Is U0636 generic or manufacturer-specific?

U0636 is a generic OBD-II code: it has the same meaning on every make and model that follows the SAE standard.

Can TuningBot remove U0636 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 U0636 is removable in your case.

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