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T.4.3.1 A Brake System Encoder or switch to measure brake pedal position or brake system pressure must be fitted to check for plausibility
T.4.3.2 The BSE must be able to be checked during Technical Inspection by having one of:
A separate detachable connector(s) for any BSE signal(s) to the main ECU without affecting any other connections
An inline switchable breakout box available that allows disconnection of each BSE signal(s) to the main ECU without affecting any other connections.
T.4.3.3 The BSE or switch signals must be sent directly to a controller using an analogue signal or via a digital data transmission bus such as CAN or FlexRay.
Any failure of the BSE or BSE wiring that persists more than 100 msec must be detectable by the controller and treated like an implausibility such that power to the (IC) electronic throttle
/ (EV) motor(s) is immediately and completely shut down.
(EV only) It is not necessary to completely deactivate the Tractive System, the motor controller(s) shutting down the power to the motor(s) is sufficient.
T.4.3.4 When an analogue signal is used, the BSE sensors will be considered to have failed when they achieve an open circuit or short circuit condition which generates a signal outside of the normal operating range, for example <0.5 V or >4.5 V.
The circuitry used to evaluate the sensor must use pull down or pull up resistors to ensure that open circuit signals result in a failure being detected.
T.4.3.5 When any kind of digital data transmission is used to transmit the BSE signal:
a. The FMEA study must contain a detailed description of all the potential failure modes that can occur, the strategy that is used to detect these failures and the tests that have been conducted to prove that the detection strategy works.
b. The failures modes must include but are not limited to the failure of the sensor, sensor signals being out of range, corruption of the message and loss of messages and the associated time outs.
c. In all cases a sensor failure must immediately shutdown power to the motor(s).