A Touran (1.8T) multi-purpose light vehicle, engine model BPL, engine management system for the Bosch ME7.5, hand-row one-speed transmission 09G (HHH).
    Symptom: start the engine idling run. Turn the cruise control (GRA) main switch integrated from the turn signal and the variable light switch control handle from OFF to the ON, and the green cruise lights on the meter display. Turn the turn signal switch handle when the car turns, and when the car completes the turn, the switch handle is automatically turned off and the cruise lamp suddenly goes out. And then how to fiddle with the GRA main switch, the dashboard cruise lights are not bright, can not set the current speed of the vehicle, cruise failure, into the factory repair.
    Fault diagnosis: after the car on the car before the first test. The fault is basically the same as the owner's description. Start diagnosis, connected to the VAS5051 diagnostic equipment for the vehicle to guide the query, in the engine control unit, steering control unit are shown the same fault, fixed speed control switch E45 signal unreliable (accidental); then enter 01-02 Fault query, there is a fault code 60895, into the 16-02 fault code 16952, fixed speed control switch E45 signal unreliable. According to the fault code prompt, E45 switch may be bad contact. Resulting in signal failure, can not transmit electrical signals. As the vehicle technology content is high, there is no similar fault-related maintenance experience. Need to first clarify the idea, under normal circumstances E45 switch is through the switch within the resistor divider sent to the J527 steering column electronic control unit input memory, according to the program configuration connection input value, processed by the microprocessor, the result is copied To its send memory. In order to process the CAN-BUS information, the J527 control unit has an additional CAN memory area for receiving and transmitting information, which is integrated in the microcontroller's chip, in fact a receive and transmit amplifier, the serial bit of the cAN module Stream logic level 0 or 1 converted to the corresponding signal level 0V or 5V, through the CAN-BUS data bus to send data at 100kB / s, sent to the J533 data bus diagnostic interface, in fact, it is a gateway (GatewayCorltorller), with From a network protocol to another protocol to convert information between the ability to coordinate data communication between high and low speed networks. Once the information is received. The gateway can perform the external read and write operation of receiving the CAN chip. Followed by the implementation of the logic information conversion information, and then perform an external write operation, the next network CAN chip for transmission programming, and then through the data bus to 500kB / s rate of data to the instrument and trigger the GRA light. At the same time, J220 engine control unit and J217 automatic transmission control unit. This time. Once the GRA combination switch is set, the SET / first-order signal data is transferred. J220, its real-time acquisition and analysis of many signals for data processing operations comparison. And then issued a command to the J338 throttle control unit. By precisely controlling the throttle opening, ME-Motronic's electronic throttle actuator has been integrated in the ETC function module to fully meet the requirements of constant speed control without the need for the driver to operate the accelerator pedal to maintain a stable vehicle speed. So when the driver turns on the GRA main switch ON. The green cruise lights on the instrument panel, when the speed of 45km / h or more, according to their own speed and then press the switch handle on the side of the SET / 1 or RES / + switch to achieve the following functions: ① set SET; ② RES ; ③ acceleration + (by 1.5km / h increments); ④ deceleration (by 1.5km / h decreasing). Rely on its unique structure. The GRA combination switch can control multiple functions.
    Analysis of this, it seems the problem should be GRA main switch, because it is and switch lights and other switch assembly integration, only to replace a set of the assembly. After troubleshooting, GRA cruise function is restored. Replacement of spare parts due to power cut. Need to use V. A. S5051 do 01 a 04-060 throttle set; 01 a 04-063Kickdowvn set, and then self-learning, do turn the corner sensor G85 set, power window anti-folder function recovery and a series of settings.
    Fault Summary: GRA main switch E45 is actually a coding switch. Trigger J1527, through the data bus to the gateway J1533. And then to J1220 throttle control unit J338. E45 contact is not good, can not be encoded lead to some failure. The two fault codes are obtained by the OBD-ll diagnostic interface through the K-line and CAN-BUS data bus respectively. Modern new high-tech content of the car, troubleshooting is simple. But the problem to be clear, the key is to diagnose. Do not talk about the gateway to confused, unable to start, available screening method one by one rule out.