Aftermarket Radio blocking obd scanner connect.

[MYVW]

98 Jetta. How do I identify the k-wire location on the radio harness? I've been told aftermarket radio is blocking connection of diagnostic scanner. Was advised to diconnect k-wire. I assume it means I should disconnect the k-wire from the aftermarket radio harness which plugs into the cars's radio harness connectors. True?

Guidance appreciated...

[mk3vdubr]

I cant think of what that wire would be... on my aftermarket harness i can identify what all the wires are doing with no extras, and my diagnostic port works fine. Unless its the blue wire used for system control for subs and whatnot, that wire should not be plugged into the harness even if its not being used for aftermarket speakers...

[MYVW]

Originally Posted by mk3vdubr

I cant think of what that wire would be... on my aftermarket harness i can identify what all the wires are doing with no extras, and my diagnostic port works fine. Unless its the blue wire used for system control for subs and whatnot, that wire should not be plugged into the harness even if its not being used for aftermarket speakers...

Thanks very much for the quick response. Funny you say the "blue" wire, I was just
beginning to suspect that wire might be the issue. I am not using any aftermarket speakers nor amplifiers. Was a simple replace of the stock radio with a Pioneer DEH 1900MP. I'll try disconnecting the blue wire thats part of the harness that came with the radio. We'll see....


Thanks again for your advice...

...Bob

[MYVW]

Originally Posted by MYVW

Thanks very much for the quick response. Funny you say the "blue" wire, I was just
beginning to suspect that wire might be the issue. I am not using any aftermarket speakers nor amplifiers. Was a simple replace of the stock radio with a Pioneer DEH 1900MP. I'll try disconnecting the blue wire thats part of the harness that came with the radio. We'll see....


Thanks again for your advice...

...Bob

Eureka....problem was the blue wire. The guys that installed the radio had the blue and blue/white wires tied together in the radio adapter harness. Once the blue wire was cut the diagnostic computer was able to connect and read the obd's. What a fiasco.

[mk3vdubr]

where did you get your radio installed? I was reading a little about the whole k-wire thing apparently it can fry certian types of scanners if the aftermarket radio is installed wrong, but if they used the adapter harness its supposed to bring the k-wire to a dead plug so for you to have that problem they would have had to of been messing around with the harness??? unless they didnt use the adapter... i thought it was interesting tho some dealerships wont even plug into a mk3 with a aftermarket radio installed for fear of frying it, but i dont think its the obdII that is the problem

[MYVW]

Originally Posted by mk3vdubr

where did you get your radio installed? I was reading a little about the whole k-wire thing apparently it can fry certian types of scanners if the aftermarket radio is installed wrong, but if they used the adapter harness its supposed to bring the k-wire to a dead plug so for you to have that problem they would have had to of been messing around with the harness??? unless they didnt use the adapter... i thought it was interesting tho some dealerships wont even plug into a mk3 with a aftermarket radio installed for fear of frying it, but i dont think its the obdII that is the problem

Was purchased and installed at BestBuy. However, I must say they have been wonderful once I was able to convince them their installation was causing this problem. The did what a first class merchant should always try to do, convert a irritated customer into a delighted customer. They did! They agreed to pay all my diognostic and repair expenses from my local mechanic, plus a $100 gift card.

Yes, it did fry my mechanics MotorVehicle Inspection Computer, as he tired to see if it would communicate with the car after the VW diagnostic computer would not. The later computer was diode/fuse protected so no damage to it. As indicated in my previous post, they had the blue and blue/white wires tied together in the adapter harness. Once the blue wire was isolated the problem was solved.

[mk3vdubr]

Thats good to hear, sounds like it was an obvious mistake on there part. My experiences with Best Buy have been bad enough where i will not go there anymore for ANYTHING but it gives me a little reasurence that maybe there not all bad.