Hitachi BED501

7F-10-22 KWP DiagnosticSessionControl RX error

Method: OBD

Issue: The tool reports an error because the ECU has rejected the request to start a diagnostic or programming session.

Solution

Carefully check the required conditions listed in the Bflash software's HELP section for this specific protocol. Ensure all conditions (e.g., battery voltage, engine temperature, ignition state) are met before retrying the operation.

To understand more

ECUs have built-in safety checks to prevent modification under unsafe or unstable conditions. This error is a protective measure, indicating that the vehicle's state (like low battery voltage or incorrect ignition status) does not meet the manufacturer's required parameters for safe flashing. Fulfilling these conditions allows the ECU to grant the necessary security access for programming.

Further Information on Hitachi BED501 - RH850

About the Control Unit

The Hitachi BED501 control unit, featuring a Renesas RH850 processor, is commonly found in modern petrol engines from Renault and Alpine. It is responsible for managing critical engine functions, including fuel injection, ignition timing, and emissions systems, and features advanced security protocols for diagnostics and programming.

Common Car Models

Renault Clio V

Renault Captur II

Renault Megane IV

Alpine A110

Renault Arkana

Dacia Duster 2

Technical Concepts Explained

Diagnostic Session Control

A command used in vehicle diagnostics (like KWP or UDS) to request that an ECU enters a specific mode, such as programming, default, or an extended diagnostic session, to allow for advanced functions.

KWP (Keyword Protocol 2000)

A common automotive communication protocol used for on-board diagnostics (OBD). It defines how data is exchanged between a diagnostic tool and the vehicle's electronic control units.

Hitachi BED501 - RH850

Errors

7F-10-22 KWP DiagnosticSessionControl RX error

Concerns vehicles from

7F-10-22 KWP DiagnosticSessionControl RX error

To understand more