One customer describe his 2013 BMW F18 525Li with 61000km mileage got trouble.The car engine warning light on and central display “Transmission malfunction”.But it can start engine and accelerate normally.More repair cases about BMW,please check here:BMW Trouble Repair
Use BMW ISID to diagnose,got trouble code as below:
Fault Code: 135401
Fault Explanation: Valvetronic: overloaded amplifier
DME temperature: Overtemperature
Valvetronic servomotor, activation: short circuit to ground
Valvetronic supply voltage malfunction.
Valvetronic: No movement identified” stored in the Digital Motor Electronics (DME)
According to the repair service information from ISTA,perform electronic valve limit position learning,but got the learning failure message.And turn off ignition the servo motor can feedback action sound.After reprogramming,the trouble code:13568 code still exit and can not be deleted.
Check the harness wire between DME and electronic valve motor,the power supply and ground work well.To implement the inspection plan, the system recommends replacing the DME and servo motor.After remove and disassemble the servo motor,mechanic found the upper part of the worm of the servo motor damaged.The position corresponding to the eccentric shaft gear also has deep marks of wear.The motor stuck symptom is consistent with the trouble code 135608.
Finally, based on the results of the inspection, replace the DME, servo motor, and eccentric shaft and delete the fault memory. Then, through the ISTA system, perform learning for the extreme position of the electronic valve system,the learning successful, and the fault is completely eliminated.