Variable Valve Timing Solenoid: Testing and Inspection

Camshaft timing control system, checking
Special tools and workshop equipment required





^ VAS 5051 and VAS 5051/1

Requirements
^ Coolant temperature at least 80 ° C
^ Vehicles with automatic transmission: selector lever in position P or N

Work sequence
^ Connect vehicle diagnostic, testing and information system VAS 5051 and select vehicle system "01 - Engine electronics" from menu. Engine should be idling.

WARNING:
^ Test equipment must always be secured on the rear seat and operated from the rear seat by a second person.
^ If test equipment is operated from the front passenger seat, the occupant could be injured by the passenger's airbag in an accident.





Display on VAS 5051:
^ Select diagnosis function "04 - Basic settings" from menu -1-.





Display on VAS 5051:
1 - Enter display group
- Using keypad -2-, enter "094" to select Display group 094 and confirm entry with Q button.





Display on VAS 5051:
- Press button -A- to activate Basic setting.
- Increase engine speed to above 2000 rpm for approximately 10 seconds.
- Check readouts in display zones -3- and 4-.





If the specification "Syst. O.K." is not attained:
- Press <- Button twice.





Display on VAS 5051:
- Select diagnosis function "08 - Read data block" from menu -1-.





Display on VAS 5051:
1 - Enter display group
- Using keypad -2-, enter "090" to select Display group 090 and confirm entry with Q button.





Display on VAS 5051:

Requirement
^ Engine idling.

- Check readouts in display zones -3- and 4-.





- Take vehicle for a test drive.
- Check readouts in display zones -3- and 4-.





- Press <- button to exit from function "08 - Read data block".

If the specifications are not obtained:
- Check valves for camshaft adjustment.

Note: If only a value between 6.0 ° cr/shaft and 16.0 ° cr/shaft is displayed during the test, the electric valve for camshaft adjustment is correctly transferring oil pressure to the mechanical camshaft adjuster, but the mechanical adjuster cannot reach its end position (for example, because it is not moving freely).