Fault Symptoms E65

Particularly when carrying out troubleshooting in the MOST system network it is important to know the precise significance of visible and audible symptoms. With this information it is possible to locate and correct faults much faster.

The starting point for locating faults should always be to pose detailed questions relating to the fault to the customer. This information can then be used to formulate initial consideration before the BMW diagnosis system is connected.

The following information should be available to the technician:

• When does the fault occur? E.g. already during engine start or while driving?
• Since when does the fault occur?
• Does the fault depend on temperature? When cold, hot or after longer period of vehicle operation?
• Do several functions fail simultaneously? If so, which?
• Is the fault still present after shutting down and restarting the vehicle?
• Was something switched on or off immediately before the fault occurred?
• Is it necessary to enter the telephone PIN after restarting the system?
• Does the radio/CD need to be switched on separately after restarting the system?
• How often does the system fail?
• How long does audio failure last?
• Can a loud clicking noise be heard in connection with the fault?
• Is the system OK again after switching terminal 15 off and on?
• What was shown on the main screen and in the assistance window?
• Does the control display fail?
• Is the display white or black or does it flicker in connection with the fault?
• Can a status line still be seen?
• What is shown after resetting the MOST bus (last menu, basic menu/start menu, BMW logo)?
• Does the CD changer make a noise after audio failure?

In addition, various factors that could also cause malfunctions in the system should be clarified:

• What control units have already been replaced?
• Did the fault symptom change after replacing control units?
• Was the light intensity reduced for the control units?
• Were the plug connections at the MOST control units checked?
• Was another or new road DVD inserted?
• What road DVD was used?
• Was something retrofitted on the vehicle or a repair carried out?
• To what CIP status (integration stage) does the vehicle correspond?
• Were other-make parts retrofitted in the electrical systems?

Based on the information provided by the customer and after examining any changes in the system it may be possible to determine faults already at this stage.

Why are these statements important? Examples from visual applications: