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IC.4.3.4 Late or non submission will prevent use of ETC, see DR.3.4.1 IC.4.4 Throttle Position Sensor - TPS
IC.4.4.1 The TPS must measure the position of the throttle or the throttle actuator.
Throttle position is defined as percent of travel from fully closed to wide open where 0% is fully closed and 100% is fully open.
IC.4.4.2 Two or more separate sensors must be used as TPSs. The TPSs may share the same supply and reference lines only if effects of supply and/or reference line voltage offsets can be detected.
IC.4.4.3 Implausibility is defined as a deviation of more than 10% throttle position between the sensors or other failure as defined in Section IC.4. Use of larger values may be considered on a case by case basis and require justification in the FMEA.
IC.4.4.4 If an implausibility occurs between the values of the two TPSs and persists for more than 100 msec, the power to the electronic throttle must be immediately shut down.
IC.4.4.5 If three sensors are used, then in the case of a TPS failure, any two TPSs that agree within 10% throttle position may be used to define the throttle position target and the 3rd TPS may be ignored.
IC.4.4.6 Each TPS must be able to be checked during Technical Inspection by having one of:
a. A separate detachable connector(s) for any TPS signal(s) to the main ECU without affecting any other connections
b. An inline switchable breakout box available that allows disconnection of each TPS signal(s) to the main ECU without affecting any other connections
IC.4.4.7 The TPS signals must be sent directly to the throttle controller using an analogue signal or via a digital data transmission bus such as CAN or FlexRay. Any failure of the TPSs or TPS wiring must be detectable by the controller and must be treated like implausibility.
IC.4.4.8 When an analogue signal is used, the TPSs 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.
IC.4.4.9 When any kind of digital data transmission is used to transmit the TPS 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 to be considered must include but are not limited to the failure of the TPS, TPS signals being out of range, corruption of the message and loss of messages and the associated time outs.