Audi A4 Cabriolet - iMPLAUSIBLE SIGNAL ---help !!!!!!!!!!!!


Registered User
I have had a major headache with this, i have replaced all the roof tray and components that are in the boot as i broke that. I have had a full VAGCOM rest done and when it read the code sequence for the roof open and shut it came up with this

Address 26: Auto Roof (8H0 959 255 )

19:19:31 Group 001: Convertible Top Status (Actual)
Not Oper. Convertible Top Control Switch
00100001 Switches && Positions I
10 1010 Switches && Positions II
30.0 Top Frame Position (G356)



Address 26: Auto Roof (8H0 959 255 )

19:13:35 Group 001: Convertible Top Status (Actual)
Not Oper. Convertible Top Control Switch
00011010 Switches && Positions I
10 1010 Switches && Positions II
138.0 Top Frame Position (G356)

Address 26: Auto Roof Labels:
Control Module Part Number: 8H0 959 255
Component and/or Version: VSG B6 CABRIO 6286
Software Coding:
Work Shop Code: WSC 00672 785 00200
1 Fault Found:

02000 - Switch Position
008 - Implausible Signal

Now apparantly the code sequence for the first few digits on the SWITCHES & POSITIONS 1 are wrong

The first set should read

00101001 but reads 00100001 (open)

The second reads

11011010 but reads 00011010 (closed)

Please can someone tell me which microswitch or switches need changing if that is the case, many thanks in advance, Nick


Registered User
Many thanks murran for that great piece of work , i can which sensor that g356 is, hopefuuly it wont be a nightmare to replace, do yuo think that Audi dealer is the best place to buy the switch/sensor ? many thanks again, Nick


Registered User
it might not even need replacing.
a 55 plate vw beetle i was looking at at the beginning of the week......
the hood would work to a point then stop when the hood down locking devices started working.
the vas5052 we have at work gave a switch implausible fault like your fault code.
running thru the guided fault finding program and looking at the switch values at different hood positions. you could see the switches for the hood down locking mech. were contradicting each other.

stripped it down, removing back seat and rear panel cards. i could see the locking devices had a min and a max position switch on each side, i pressed each switch in turn with my finger and one didnt click on the n/s unit, but on bending the little metal tag/lever back slightly it did click. on pressing it again like i did the first time, it now clicked.

and thats all it was! two little switches contradicting itself making the ecu think the n/s roof down locking mechanism wasnt working.