BMW 750Li flame failure cases for no reason

BMW 750Li flame failure cases for no reason Model: 750Li engine chassis E65 N62
Symptom: vehicles in the process, there have been several auto turn off problem, every time
the car again barely. But after the last turn off, however hard, start the engine do not
have any signs, vehicles had to be dragged into the repair shop to be checked.
Troubleshooting: First the test, the ignition key into the CAS outlet, press the start
button, the dashboard appears "Drivingstabilityaffected" warning message, the meaning of
driving stability system fault. Slam the brake pedal, hold down the start button, the
dashboard appears "dynamicdriveinactive" warning, meaning the dynamic driving system is not
activated. Ready to lift the vehicle into the repair station, but no matter how toggle on
the steering column shift lever, transmission, have been locked in the P file, and the
dashboard display "Traansmissionfailsafedrivemoderaterly" warning, meaning failure to start
automatic transmission Safe Mode. In addition, throughout the testing process, dashboard
engine warning light had not lit, indicating that DME control module of the power supply is
not connected.
GT1 tester connected to self-diagnosis, click on the Quick test, the entire vehicle
electronic control system into the scanner, the detector did not search DME, VTC electronic
control system. After scanning the information into the list of interface failure, a number
of electronic control systems have fault codes stored records are as follows:
1CIM central chassis electronic control system has a fault code stored
5D35 vertical Hall-effect sensor no signal, the current does not exist
2ZGM (CAN / Byteflight) central gateway electronic control system has five fault codes
stored
D711EHC control module KCAN bus communication failure, the current does not exist
9C90IHKA DME control module engine control module communication failure, the current exists.
D1E1ARS DME control module CAN bus from the cooling temperature signal failure, the current
existence of
D98FCIM system control module engine control module information is missing, currently
exists.
CF16EGS control module engine control system information is missing, currently exists.
3EDC electronic damping control system there are two fault codes stored
5FFD electronic damping control system wake-up bus failure, the current existence of
5FFE bus voltage on the negative short-circuit current exists
4SCM-SIM electronic control system has a fault code
93FC system voltage is too low, does not currently exist.
Detector will return to GT1 diagnostic main menu, click on the Quick Delete, the entire
vehicle electronic control system for the fault code cleared, after re-query CIM, EDC, SCM-
SIM electronic control system trouble code is cleared, ZGM Central Gateway only the
electronic control system malfunction code D98FCF16. Try to start the vehicle, the engine is
still no response. GT1 tester can not be combined with the previous search engine control
system can determine the fault appears in the DME control module and its connections, the
DME control module so check the power cable ground wire, click on the function selection
key, find the DME electronic control system The power supply circuit diagram, the figure
shows three fuses were used, components are marked F34.F40.F001. the actual examination,
were good. To rule out the possibility of bad connections in the engine compartment of the
electronic control box to find the right DME control module, the control circuit, the power
and ground pins for testing, are normal, thus excluding the power supply side of the fault
may sex.
The next step is to identify the GT1 tester DME control module search not the reason.
According to information we can see, VTC use LOCAN bus to communicate with the DME control
module connector, LOCAN bus belonging to the engine control system LAN bus, VTC control
module only through the DME control module can be the gateway control module identification,
and thus can not search GT1 Tester to. So long as the DME control module to solve the
communication problems, VTC communication problems will be solved. Relevant information,
that is PTCAN DME control module bus users, the bus is also connected ARSEDCEGSDSCEMF other
control modules, only DME control module is not searchable, indicating that there are two
possibilities, one car DME control module is damaged, two DME is a bus connection control
module PTCAN bad.
PTCAN bus measurement
Resistance measurement method. In order to avoid signal reflection effect, PTCAN bus
with a LOW / HIGH two-wire, wire, connecting a 120 ohm resistor, as an alternative
resistance. Disconnect the control module in the wiring harness plug, you can use the method
of measuring the resistance between the double check, because the line is parallel, the
resistance should be 60 Euro DC voltage measurement method. Turn the ignition switch and the
engine not operating under the conditions by measuring two-to-ground voltage, to determine
whether there is a short or open PTCAN failure. The standard values ??are measured line
2.4VHOGH line LOW 2.6V
Waveform measurement. In turn the ignition switch and the engine is not running
conditions, you can use the oscilloscope PTCAN bus signal waveform measurements, the
measurement should be the standard value as LOW output 2.5, ~ 3.3V square wave signal, HIGH
output line should be 3.5 ~ 5.0 v square wave signal.
DME control module wake-up function, which is achieved through the bus, which means that
the vehicle starts the process, the start button signal is not sent directly to the DME
control module, but first sent to the control module CAS, CAS control module in the ignition
key After testing the legality of, and through a separate data line, wake to the relevant
instructions issued by the control module (ie the 15th power signal), which is called 15WUP
bus data lines, along with PTCAN bus, designed with a protection sets the special wiring
harness. The next job is to PTCAN test bus and the bus 5WUP actual measurements. Consistent
with the standard measurement system. To be prudent, the DSC control module has been
measured, the measurement value is completely normal. At this point you can determine the
cause of the malfunction DME control module damage. After the failure to replace the DME
troubleshooting summary E65 chassis models, using the vehicle's communication bus network,
and his central network control module (ZGM) is the GT1 tester and the vehicle electronic
control system diagnostic communication interface, if PTCAN DME can not be found on only to,
you can issue simple, direct detection of DME on the line.