UK-POLOS.NET - THE VW Polo Forum

Hi, my second unplug question. Am doing a lot of mods, but i still am not certain how robust vehicle ECUs are to this type of thing.

I am having to unplug my speedometer from the 2013 polo bluemotion so I can test another one with upgraded Blue LEDs (but not coded to my car) just to check its works and looks how it should. If I like it a friend will recode the blue one using software. Before I arrange doing this, can anybody confirm if this will be ok.

1. I understand plugging in the blue unit without being coded the car will not start, but will it at least light up its blue LED’s so I can check it ?

2. That plugging in an uncoded unit (presuming it’s a sound unit) wont throw a wobbler in my ECU, and I can still plug the old speedo back in and the car will start ?

I would strongly recommend against doing this

iichel wrote: Wed Apr 20, 2022 4:38 pm I would strongly recommend against doing this

Why?
I've never had a problem doing similar tests...

Because it will cause your ABS to lose its coding (VIN mismatch between the cluster, ECU and VIN based ABS coding). And your radio will ask for the code.
Unless the cluster is already coded to your car. Then only the radio will ask for the code.

iichel wrote: Wed Apr 20, 2022 8:35 pm Because it will cause your ABS to lose its coding (VIN mismatch between the cluster, ECU and VIN based ABS coding). And your radio will ask for the code.
Unless the cluster is already coded to your car. Then only the radio will ask for the code.

So, this could be the reason behind frequent threads across the VW Group motoring forums concerning "ABS controller lost its coding", I've always wondered why that could have happened to so many people without some external influence.

iichel wrote: Wed Apr 20, 2022 8:35 pm Because it will cause your ABS to lose its coding (VIN mismatch between the cluster, ECU and VIN based ABS coding). And your radio will ask for the code.
Unless the cluster is already coded to your car. Then only the radio will ask for the code.

thanks for the headsup, glad I asked now. So are you saying that even if was to not bother with the replacement cluster, but just unplug my existing cluster, (which i was going to anyway for other mods) then plug it back in my radio would need its code ?

The radio will ask for the code as soon as it talks to a different cluster than it's used to.

Radio code came with original car paperwork ( manual, service book...) at least for my car.

iichel wrote: Wed Apr 20, 2022 8:35 pm Because it will cause your ABS to lose its coding (VIN mismatch between the cluster, ECU and VIN based ABS coding). And your radio will ask for the code.
Unless the cluster is already coded to your car. Then only the radio will ask for the code.

OK thank you . My fault , I did not remember that I am a very prepared boy and I always have the solution at hand for this type of incident.

As soon as I knew/seeed the code of my radio/nav sys, it was sealed in my mind.
For the other incident/s, previous VCDS Autoscan.

amer6R wrote: Thu Apr 21, 2022 3:58 am Radio code came with original car paperwork ( manual, service book...) at least for my car.

Mine too, I told the seller that I wouldn't buy the car if he didn't provide it to me.

ciclo wrote: Thu Apr 21, 2022 4:00 am

amer6R wrote: Thu Apr 21, 2022 3:58 am Radio code came with original car paperwork ( manual, service book...) at least for my car.

Mine too, I told the seller that I wouldn't buy the car if he didn't provide it to me.

codes not in my RCD310 manual.. thankfully I see online services provide these for £5.

So, I'm guessing with VW Polos, it was not until the 6C was launched that radio codes, as in a set of numbers on a scrap of paper, were done away with, I got no radio code with my wife's August 2015 VW Polo when it was bought new as I thought that the radio was "assigned" to that chassis at factory and if replaced, I would need to get CP removed and the next radio "assigned" to that chassis by VW Mothership - which was exactly what I needed to do when I bought a used "but with DAB" radio for my 2011 Audi S4 - ie the VW Group Indie would, when I handed my car in for getting that new radio "assigned" to my car, connect up to Audi Mothership and it would check if that next used radio was logged as being stolen and if not convert it from being a "previously assigned" radio to a "virgin" radio, and then add it to my car.

Yes, the component protection was mainly introduced to the VW's along the MQB platform, with some small exceptions for the Discover Media PQ devices and some other parts like ACC radars. These parts also have CP but are provided to the PQ25/PQ35 platform, like the Transporter T6, the latest Sciroccos and the Passat NMS.