VAG help needed

[macattax]

I have posted this on navplus forum but I may get just as much help here maybe more.

I was checking to see what cabling was behind my dash over the weekend to see what kind of work needed to be done for a Nav+ project.
The dash removal went fine no problems I unplugged the 3 sockets from the back of the dash and then had a good look around.
I put all the sockets back into the dash and the screwed the dash back into place.
Everything seemed fine the radio worked ok etc.
When I tried to start the car it took maybe 8 tries felt like the battery was low or something (which it isnt) car started and everything seemed fine.
As I was driving I went over a bad bump in the road and the radio went blank and the sound cut out there is a mecahnical noise coming from the radio and thats all.
If I slap the radio it will come back on also if i slap the dash the radio will come back on too.
I checked all the cables again and everything seems fine.
So I did a vag scan yesterday to see what errors it might find and it threw up a few that I am very worried about.

Here are the errors it found.

Address 01 -------------------------------------------------------
Controller: 4B0 906 018
Component: 1.8L R4 5VT 01 0004
Coding: 05001
Shop #: WSC 06335
2 Faults Found:
18010 - Power Supply Terminal 30: Voltage too Low
P1602 - 35-10 - - - Intermittent
18084 - EPC Warning Lamp (K132) Circuit: Electrical Malfunction
P1676 - 35-10 - - - Intermittent
Readiness: 0000 0000

Address 56 -------------------------------------------------------
Controller: 4B0 035 186
Component: Radio 0001
Coding: 00207
Shop #: WSC 06335
1 Fault Found:
00854 - Radio Display Output in dash Panel insert
49-10 - No Communications - Intermittent


Does anyone know what is causing these errors and how it can be fixed?
I hvae cleared the faults but they still come back.

 

[macattax]

Bump! anyone?

 

[shineydave]

looking at the wiring diagrams you've got a bad connection on plug T32 which goes into the back of the dash, that's the plug which carries the radio, accelerator and main power from the ignition switch.

now the confusing bit is the drawings describe it as a 26 pin connector but shows it as a 32 pin connector. depending on which page i look at there's 2 x 32 pin connectors or 1 x 26 and 1 x 4 pin, it doesn't mention 3 connectors though, only 2 so which connector it actually is is anyones guess. i'm going to suggest it's a yellow (but it might be blue) connector. in any case it's the one with the most wires going into it.

when you pulled the plugs you haven't managed to damage the ribbons on the back of the board have you?, if i recall the plugs are connected directly to the board and can quite easily pull away from the ribbons on the circuit boards.

 

[macattax]

God I hope I havent damaged ribbons.
Its the plug to the far right of the dash that controls the radio.
I will need to open up that connector then to check the wires havent come loose then.
So from what you say it may be a yellow or blue wire that came loose?
If they are ok how do I check if the ribbons are ok?
Do I need to open up the dash unit more?

 

[shineydave]

i meant a yellow or blue plug, it could be the ribbon on the circuit board, not the plug, i think the plugs are pretty robust. you'll prolly be able to see any damage as the connector on the board will be loose

 

[macattax]

There were some connectors which would slip in and out of the connector quite loosely. I couldnt figure out how to tighten up the connection once I had it pushed it into the connector. 2 wires are quite loose so how do I make them fit more snug into the connector?

 

[shineydave]

there should be a tang on them that locates inside the housing, just bend them out a bit

 

[macattax]

OK I tried that but the radio still goes off and on when going over bumps!
So it must be the ribbon then?
I tried to get the plastic cover off but its a real pain in the *** to get all them clips to stay open. I open say 3 clips and the start to open another clip and then the ones I had open will clip into place again ***!
Is the ribbon cable just below this plastic cover?

 

[shineydave]

when i say ribbon i mean the soldered tracks on the circuit board, i've had it before when unclipping the plugs that the socket on the board has pulled away from the board damaging the contact with the tracks, had to resolder the plug back in place

 

[macattax]

So if you relaese all the tabs is that socket under the plastic?
Im quite skilled with the soldering gun so I may check this out this evening.

 

[macattax]

I opened up the instrument panel over the weekend to look to see if the soldering on the board was damaged but all looks fine.
The connector does not feel loose and the soldering on the circuit board seems intact. Could it be possible that while I was moving the cables about that the cable on the back of the radio came loose?
I dont have radio removal keys yet but they are in the post from Germany so should have them soon.
If its not a loose connection at the radio then I will be very annoyed indeed.

 

[macattax]

Took the car to an auto elec specialist.
****** hell what an embarrasing outcome lmao it was a 20p piece hopping around inside of the headunit.
My wee fella is the likely suspect for doing this.
I didnt have the removal keys otherwise I would have checked this.
So basically I checked everything else except the actual headunit lol.
It still cost me €30 to have this looked at which was a 5min job.
But I guess for peace of mind its not a bad price.
Gremlins eh!