Drain converter

Expert information

Until now it was necessary to open a special oil drain plug in the transmission, in order to drain the waste oil from the converter when changing the oil in the DIWA.5 transmission. Therefore the mechanic inevitably comes into contact with waste oil. This is to be avoided in future. The oil change support is a method for draining as much waste oil as possible from the converter without having to open the internal plug. The following conditions must be met for oil change support / converter draining:

Transmission oil temperature > 60°

Transmission in neutral position

Engine is running

Vehicle not running

Once all conditions are met, the converter can be drained. To do so, the PB solenoid valve is switched on for 2 minutes. At the same time, the WP solenoid valve is activated for 0.5 seconds. After the converter has been drained, the engine can be shut off and the oil drain plug can be opened. Successful draining of the converter is saved together with the time stamp and transmission mileage in the control unit and serves as proof of correct maintenance. The history storage of the control unit is used for this purpose. The Oil Change Support / Drain Converter function can be called up in all diagnosticModes. The control unit provides protection against dangerous conditions caused by the control of solenoid valves by diagnostic services. The oil change support is performed in two steps:
The diagnostic service StartRoutineByLocalIdentifier is used to start the converter draining. A corresponding LId is read cyclically via the ReadDataByLocalIdentifier service, in order to monitor the diagnostic information that is relevant to the oil change.
The LId can also be read at any time independent of the converter draining. Procedure: The procedure is started by the StartRoutineByLocalIdentifier diagnostic service. If the conditions for performing the oil change support are not met, the control unit will give a negative response. The reason for rejecting the control can then be read in detail in the LId. The KWP does not offer all of the NRCs (Negative Response Code) required for this. If there are no obstacles for starting the procedure, the control unit will give a positive response and simultaneously start the solenoid valve required for the oil change support. The status of the oil change support can be monitored at any time using an LId (Local Identifier). This LId also provides detailed information on possible obstacles that might cause an abortion of the action.

The StartRoutineByLocalIdentifier service with the routineLocalIdentifier = "Flush" parameter is used to start draining of the converter. With the DIWA.5 transmission, solenoid valves PB and WP are switched on for this purpose to drain the converter as completely as possible while the engine is running. Solenoid valve PB is switched on for 2 minutes, solenoid valve WP for 0.5 seconds. Solenoid valve PB remains on, even after the converter has been drained, until the engine is shut off.