01/11/2026
🟢Volkswagen Tiguan
🟢 Transmission DQ381
🟢 CUSTOMER COMPLAINT
Transmission fault message on dash, limp mode on
🟢 Fault code stored
P1735 Position Sensor for clutch 1 Electrical Malfunction
🟠 We confirmed that Clutch pressures sensor 1(K1) G545 had an implausible value at -0.94 Bar .
The pressure sensor had failed which causes the TCM not able to control the clutch and needs to be replaced.
🟠Thanks to John Gains and Andy Young for information on how to do this repair myself.
John even posted me a couple of sensors so I could get the job done quickly for my customer 👌.
The original sensors are mounted with factory spot welds on all 3 points. Drilling these out are quite tricky given that the actual area of the sensor is about 1/2 the size of a key battery. Some techniques include cutting off the "wiggly bars" completely and using wire to bridge the gap however if your careful enough we can simply drill out each weld and the Solder the sensor to the 3 mounting points.
🟠I was really happy with my repair if I'm honest 😉
🟠 I have added some images and a paragraph of Mechatronic unit pressure sensor operation
In the DQ381 gearbox, the mechatronic unit uses pressure sensors to monitor the hydraulic pressure supplied to the two clutch packs (K1 and K2). These sensors provide real-time pressure feedback to the transmission control unit (TCU), allowing it to regulate the hydraulic pressure applied to each clutch through electronically controlled solenoid valves. This ensures the clutches engage and disengage at the correct pressure and timing, providing smooth gear changes and preventing clutch slip or excessive wear. By continuously monitoring pressure, the mechatronic unit can adapt clutch operation to driving conditions, engine torque and gearbox temperature.