A few days ago, the power liftgate on my Volkswagen Tiguan began malfunctioning. Pressing the soft-touch button on the hatch unlocks the trunk, and it starts to open but stops prematurely. Holding the button allows it to open incrementally, requiring 4-5 attempts to fully open. Once open, the power closing feature is completely unresponsive, forcing manual closure. While the owner’s manual states that manual closure is permissible, it feels unnatural and potentially damaging to the power liftgate mechanism.
TrunkLidButtons.jpg
The interior trunk release buttons, including the auto-close button on the left, are also unresponsive. Adding to the mystery, the LED light within the right-side trunk lid switch, typically illuminated when the hatch is open, remains off.
VCDS Scan Reveals No Faults in Tiguan Trunk Electronics
A VCDS scan of the vehicle, specifically module 6D – Trunk Electrics and the BCM, revealed no fault codes. This is perplexing given the clear malfunction. The complete Auto-Scan results are included below. While the car is still under warranty, understanding the potential cause is desirable.
Possible Causes and Solutions for a Malfunctioning VW Tiguan Trunk
Although no fault codes were found, several possibilities could explain the issue:
- Faulty Trunk Lid Switch: The unresponsive buttons and unlit LED suggest a potential problem with the switch assembly in the trunk lid. This could involve a broken connection, damaged wiring, or a malfunctioning switch component.
- Wiring Harness Issue: Damage or a loose connection within the wiring harness that connects the trunk lid switch to the liftgate motor could be the culprit. This might require a visual inspection and continuity testing.
- Liftgate Motor Malfunction: While less likely given the incremental opening, a problem with the liftgate motor itself could be contributing to the issue. Further testing of the motor might be necessary.
- Software Glitch: Although less common, a software glitch within the Trunk Electrics module could be interfering with proper operation. A software update or reset might resolve this.
Complete VCDS Auto-Scan Data for VW Tiguan Trunk Issue
The following data was obtained from a full VCDS Auto-Scan of the affected Tiguan:
Tuesday,18,April,2023,18:31:43:10821 VCDS -- Windows Based VAG/VAS Emulator Running on Windows 10 x64 VCDS Version: 23.4.0.1 (x64) HEX-NET CB: 0.4634.4 Data version: 20230228 DS348.0 www.Ross-Tech.com VIN: 3VV4B7AX8JM153175 License Plate: Chassis Type: AX-VW37 (3Q0) Scan: 01 02 03 05 08 09 10 13 15 16 17 19 22 29 2B 36 39 3C 42 44 47 4B 52 5F 69 6C 6D 75 A5 BB BC CA D6 D7 ... (Full scan data as provided in the original post)The lack of fault codes in the VCDS scan presents a challenge in diagnosing the root cause of the Tiguan’s trunk malfunction. Further investigation, potentially involving more advanced diagnostics at a dealership, might be required to pinpoint the issue and implement the appropriate solution.
