Tag Archives: GWS

BMW 523Li sedan GWS line fault

Mileage of about 80,000 km, models is the F18 BMW 523Li sedan 2012 . Users reflect: This vehicle can not change gear when travel, instrument displays “shift lever can not shift,” the central information display shows “shift lever failure, may not switch gears.”

Troubleshooting: Vehicle towed back to the shop after checking found no bright lights on GWS, first connect ISID diagnostic testing, failure to read as follows:

· CF17A1 information (status: shift button, 0x197) Missing: EGS receiver, GWS transmitter

· CF17B1 information (status: shift button, 0x197) Missing: EGS receiver, GWS transmitter

· CF1701 shift button interface : ( shift button states: communication complete failure, 0x197) signal is invalid

· S0001 unable to communicate with the following devices: the shift button

The GWS fault code refers to the shift lever switch, shift switch (GWS) by the electronic control unit and shift lever components. Sport button (EDC button) has been integrated into the shift switch, an integrated sensor to detect the shift lever position and the shift of the locking member unintentionally in the electronic control device. Shift switch (GWS) is used to select automatic transmission with Steptronic mode and a sport mode programs running gear. Transmission shift switch is mounted in the front portion of the center console area of ​​the vehicle and is designed as a dedicated control module. Not mechanically but electronically controlled transmission by using a shift switch. Using the shift lever can choose from the following location:

· Function P for parking via a dedicated button on the steering shift switch

· For reverse gear

· For neutral

· For driving = automatic operation mode

· M for manual operation mode = Steptronic; S for Sport mode with automatic operation mode program = sporty characteristic line

A locking member to prevent inadvertent switching to position R. To cancel locking the brakes by pressing a spoon in addition to the brake pedal, but also must press the unlocking button on the shift lever. In the shift switch (GWS) for the three locking pieces installed a total of three actuators. For automatic reset bit from a manual transmission to automatic bit locking and automatic reset manual transmission bits, using motors in series with a transmission mechanism. The locking member in the R direction, the shift lever position, using a two-way, spring-centered double magnet (electromagnet). The shift lever position D along the direction of the locking member, using a spring-loaded single magnet (electromagnet). The locking member from the bus terminal KL. 15 plays before turning power. So make sure that any shift schedule in case of failure does not lock automatically run mode through the installation of the actuator under.

With the sensor without contact GWS shift lever position detection, and forwarded to the transmission control system (EGS) by PT-CAN.

· 7 Hall sensors detect the vehicle longitudinal direction shift lever position

· 4 Hall sensors detect the vehicle lateral shift lever position

The shift lever is configured to be the indicator function of the shift map, and the display position P, R, N, D, M / S. With the light-emitting diode (LED) in the shift map shown in linked into the driving gear. When the electronic transmission control system (EGS) has been performed in this state driver’s intention and feedback via the bus through a message to the shift switch (GWS), was shown in the figure hanging shift into a driving gear. As long as the PT-CAN bus communication or PT-CAN2 bus activation function indicator has been activated.

To improve reliability, the shift switch position signal through the PT-CAN and PT-CAN2 bus transfer. So that when the PT-CAN failure will also send a signal to the EGS. For safety reasons do not need to send this signal. Its safety is guaranteed by the counter-alive signal or the complementary signals. GWS through PT-CAN wake to wake up on the high wire. GWS itself does not have the ability to take the initiative to wake up.

Select the fault content execution “AT2461_GWSVER- shift button (GWS) power supply diagnostic” test plan, diagnostic system can communicate with GWS. Analyze possible causes are as follows:

· Vehicle network voltage is too low

· Control Module powered damaged

· Communication lines damaged

Then bring up the testing program in accordance with the requirements of the relevant circuit diagram GWS controlled basis to check.

Power Check the F64 fuse measuring GWS normal, 12V voltage, not blown damage; an inspection GWS’s foot-powered S45 * 1B for 12V voltage measurements 5 feet grounded properly; check the measurement of S45 * 1B GWS 2 feet 15WUP have 12V voltage, normal. Check measuring GWS’s 545 * 1 B 3 feet and 4 feet, PT-CAN signal voltage is normal; check the measurement GWS S45 “1B 6 feet and 7 feet, PT-CAN2 signal voltage is normal and other normal vehicle swap GWS. conduct a trial run, the results still can not rule out the gear fault indicator .GWS not lit, the fault is not the same as before the change, the fault car GWS installed on other vehicles can be used normally, indicating that the problem is not the GWS.

Measured from the beginning again, and found GWS S45 * 1B foot sometimes no electricity. Unplug the fuse is not blown damage inspection F64, F64 fuse measurements have 12V voltage supply terminal. Then measure the F64 fuse between GWS S45 * 1B is a foot wire is normal, not interrupting a short circuit. The F64 fuse installed back, shaking fuse line and GWS lines tested and found GWS S45 * 1B is a foot and sometimes no electricity. Hand to suppress the F64 fuse, it has been the normal power supply. Description is connected to terminals F64 fuse in question.

Remove the front fuse box Z1 * 8B plugs, found Z1 * 8B of 4 feet not fixed, it will move backward. Continue removing the Z1 * 8B of four feet, found four anti-card has been broken foot, causing the pins can not be fixed in the plug top, causing GWS sometimes lead to supply virtual access function failure. Z1 * 8B plug position in the junction box shown in Figure 2.

Replacing Z1 * 8B sockets and connectors, delete the fault memory, test troubleshooting.

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