Navigating the complexities of modern car diagnostics can be daunting, even for seasoned DIY enthusiasts. Recently, an Audi A7 owner encountered a perplexing issue with their vehicle’s rear spoiler, turning to the VCDS (VAG-COM Diagnostic System) for answers. This article dives into their experience, exploring the fault codes, troubleshooting steps, and potential solutions for an Audi A7 Rear Wing malfunction. We’ll break down the diagnostic process, examine the rear spoiler mechanism, and offer insights for those facing similar challenges.
Decoding VCDS Fault Codes: The First Step in Diagnosis
The journey began with a VCDS autoscan, revealing a primary fault related to the rear spoiler. The fault code indicated a problem with the “Limit Switch for Rear Spoiler Movement (F135/F136),” accompanied by an “Implausible Signal” error. This immediately suggested a potential issue within the spoiler mechanism itself, possibly involving the sensors that dictate the spoiler’s position. Alongside this, there were also intermittent fault codes for the fuel filler cap and glass break sensors, which were noted as clearable and less immediately concerning than the rear wing problem.
To understand the depth of the issue, it’s crucial to interpret these codes correctly. A fault in the limit switch circuit (F135/F136) could mean several things: a faulty sensor, wiring problems, or even mechanical obstruction preventing the spoiler from reaching its intended positions. The “Implausible Signal” error further reinforces the idea that the control system is receiving incorrect or inconsistent data from the spoiler’s position sensors.
Friday,10,April,2015,11:19:15:11367 VCDS -- Windows Based VAG/VAS Emulator
VCDS Version: 14.10.2.0 Data version: 20150311
www.Ross-Tech.com
VIN: WAUZZZ4G3CN Mileage: 34913km-21693mi Repair Order:
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Chassis Type: 4G (4G0) Scan: 01 02 03 05 08 09 10 15 16 17 19 30 36 3B 42 44 46 52 53 55 5F 62 6D 72
VIN: WAUZZZ4G3CN Mileage: 34913km-21693miles
01-Engine -- Status: OK 0000
02-Auto Trans -- Status: OK 0000
03-ABS Brakes -- Status: OK 0000
04-Steering Angle -- Status: OK 0000
05-Acc/Start Auth. -- Status: OK 0000
08-Auto HVAC -- Status: OK 0000
09-Cent. Elect. -- Status: OK 0000
10-Park/Steer Assist -- Status: OK 0000
15-Airbags -- Status: OK 0000
16-Steering wheel -- Status: OK 0000
17-Instruments -- Status: OK 0000
19-CAN Gateway -- Status: OK 0000
30-Special Function II -- Status: OK 0000
36-Seat Mem. Drvr -- Status: OK 0000
3B-Sensor Elect. -- Status: OK 0000
42-Door Elect, Driver -- Status: OK 0000
44-Steering Assist -- Status: OK 0000
46-Central Conv. -- Status: Malfunction 0010
52-Door Elect, Pass. -- Status: OK 0000
53-Parking Brake -- Status: OK 0000
55-Headlight Range -- Status: OK 0000
5F-Information Electr. -- Status: Malfunction 0010
62-Door, Rear Left -- Status: OK 0000
6D-Trunk Elect. -- Status: OK 0000
72-Door, Rear Right -- Status: OK 0000
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Address 46: Central Conv. (J393) Labels: 4H0-907-064-46.clb
Part No SW: 4H0 907 064 BN HW: 4H0 907 064 BN
Component: BCM2 2.0 H31 0333
Revision: 00002001 Serial number: 0161758965
Coding: 013B062220B9BC0083200A0400010000000000000000000000000000000000
Shop #: WSC 02391 785 00200
VCID: 76E3DB26C1EB5A91443-8023
Subsystem 1 - Part No: 4G0 951 177
Component: DWA-Sensor H01 0010
Subsystem 2 - Part No: 1K0 951 605 C
Component: LIN BACKUP HO H05 1501
Subsystem 3 - Part No SW: 4G8 959 252 HW: 4G8 959 252
Component: HSP-SG H09 0027
3 Faults Found:
03132 - Limit Switch for Rear Spoiler Movement (F135/F136)
008 - Implausible Signal - Intermittent
Freeze Frame:
Fault Status: 00101000
Fault Priority: 2
Fault Frequency: 58
Reset counter: 202
Mileage: 34611 km
Time Indication: 0
Date: 2015.03.27
Time: 15:53:15
01403 - Glass-Break Sensors; Rear
011 - Open Circuit - Intermittent
Freeze Frame:
Fault Status: 00101011
Fault Priority: 2
Fault Frequency: 15
Reset counter: 201
Mileage: 34857 km
Time Indication: 0
Date: 2015.04.07
Time: 13:56:54
02615 - Fuel Tank Cap; Lock
009 - Open or Short to Ground - Intermittent
Freeze Frame:
Fault Status: 00101001
Fault Priority: 2
Fault Frequency: 1
Reset counter: 202
Mileage: 34913 km
Time Indication: 0
Date: 2015.04.09
Time: 15:19:40Investigating the Audi A7 Rear Spoiler Mechanism
Driven by the fault code, the Audi A7 owner decided to delve into the rear spoiler mechanism itself. They noted that the spoiler was exhibiting erratic behavior, continuously moving up and down until it eventually triggered a fault. Upon disassembly, a broken plastic shaft support within the mechanism was discovered, suggesting a potential mechanical failure point.
Image: Close-up view of the disassembled Audi A7 rear spoiler mechanism, highlighting a broken plastic component. Alt text: Broken plastic shaft support in Audi A7 rear spoiler mechanism.
The owner’s inspection also focused on the limit switches or proximity sensors, crucial for the system to know the spoiler’s position. They observed what appeared to be a limit switch at the motor’s drive end, interacting with a white sprocket. However, the accessibility and removability of these sensors were limited compared to older spoiler designs, making individual sensor replacement challenging. The complexity of modern Audi electronics is evident here, with potentially integrated sensors that are not easily serviceable as separate components.
Image: A detailed view of the motor end of the Audi A7 rear spoiler mechanism, pointing out a potential limit switch or sensor. Alt text: Possible limit switch location on Audi A7 rear spoiler motor.
Image: Internal components of the Audi A7 rear spoiler mechanism after disassembly. Alt text: Internal view of Audi A7 rear spoiler mechanism showing gears and components.
Seeking Professional Advice and Considering DIY Solutions
Facing a potentially complex repair, the Audi A7 owner sought advice from a local independent mechanic. The mechanic’s diagnosis was vague, suggesting a sensor replacement for a significant cost without providing specific part numbers or detailed explanations. This lack of clarity, coupled with a high estimated price, prompted the owner to explore DIY solutions further.
Undeterred, the owner considered purchasing a used Audi A7 drive unit from eBay as a potential replacement part. However, a crucial question remained: was the fault solely within the drive unit itself, or could the issue lie with the spoiler controller? Simply replacing the drive unit might not resolve the problem if the controller was sending erroneous signals or misinterpreting sensor data. This highlights a common challenge in modern car repair – pinpointing the exact faulty component within interconnected electronic systems.
Image: An overview of the Audi A7 rear spoiler mechanism before disassembly, showing its overall structure. Alt text: Audi A7 rear spoiler mechanism original condition before repair attempt.
Before proceeding with parts replacement, the owner wisely considered further diagnostics, such as continuity testing of the limit switch wiring back to the controller. This step, although not performed immediately, represents a sound approach to isolate the fault. By testing the wiring, it’s possible to rule out harness issues and further narrow down whether the problem resides in the sensors, the drive unit, or the controller.
DIY Success in Another Area: Antenna Repair
Adding a note of DIY success, the owner mentioned resolving a separate “antenna open circuit” fault. Faced with a costly quote from Audi for a new rear windscreen, they ingeniously repaired the antenna using conductive silver paint and insulation tape for a fraction of the cost. This demonstrates both resourcefulness and a valid reason to explore independent repair options before resorting to expensive dealership services.
This Audi A7 rear wing troubleshooting case illustrates the blend of diagnostic tools, mechanical investigation, and problem-solving required for modern car repairs. While the rear spoiler issue remained unresolved at the time of writing, the detailed VCDS scan, mechanism inspection, and consideration of various repair strategies provide valuable insights for anyone facing similar Audi A7 rear wing challenges. Further investigation, potentially including wiring checks and careful consideration of controller compatibility with a replacement drive unit, will be crucial in finding a definitive solution.
