Looks like you have codes for a low battery. If you haven't changed it out, I would maybe do that. Low voltage can cause all sorts of funky things to happen.

 

the battery has been replaced yesterday with a new battery. it has not changed the symptoms.

 

Since it is a new battery check the cables make sure they are tight and the battery voltage is getting every place it should. A multimeter is your friend in this trouble shooting endeavor

Without the car running check your battery voltage, it should be 12.6-8, what ever it is you should have that same voltage to the bolt on your starter the bolt on your alternator and on each side of the fuses on top of the battery. If any of these places show less you've got a problem with the wire.

 

I have checked all those places with a multimeter and All have 12.7 volts

 

Since, you have VCDS; this video, might be helpful in understanding the bus system and checking for bus status, possible narrowing down of component failures.

 

Did you clear the codes and see what comes back? You have a bunch of codes that are a result of low voltage from the previous battery. Try clearing the codes and then disconnecting the battery cables holding them together for about a minute then reconnect and see what you have.

 

I am familier with the bus system and k line in this car, all the cables and connectors asociated with this communication has been checked and look ok. no rodent damage or corrosion on the connections.

 

all of the low voltage codes cleared with the new battery. most modules are communicating with vcds but the ecu, immo, can gateway and instruments are not communicating with vcds or each other. the enigine will start and then the immo kills it when the key is released to on. the immo light in the instrument cluster started blinking when this started. I am currently cheking the wire harness for any issues between these modules.

 

Have you tried a hard reset like I described above? Holding the disconnected battery cables together for a minute or so. Sometimes this will reset the ecu and clear some really weird
issues.

 

Definitely, try the hard reset, of the ecu; charging issues, can cause the immobilizer to go goofy and kick on the immobilizer, for no particular reason (aside from low voltage). A test of the charging system; to confirm, it is working correctly, is always a first step on these cars.

If the hard reset of the ecu, doesn't make the immobilizer stop kicking on; I would confirm, the immo issue with a full auto scan. Typical, immobilizer faults; will throw a trouble code, normally this would be:

"17978 (P1570) Engine Start Blocked by Immobilizer"

17978/P1570/005488 - Ross-Tech Wiki

wiki.ross-tech.com

If the code comes up; that would confirm, a immobilizer issue is present. Here is a excellent overview of the immo system and how it works.

VW immobilizer technical information and problem troubleshooting

How to troubleshoot VW immobilizer and fix, bypass or detele the immo if car won't start or engine shuts off

www.myturbodiesel.com

Consistent, ongoing immobilizer activation; would then, require troubleshooting to narrow down the issue or another option, is to ship out the ecu, for a immobilizer delete service. This is a common "work around"; for immo issues, that owners or mechanics do, when they are not able to figure things out. We are seeing immo issues become more of a issue; as these cars age and many electrical issues come up, various parts die or wiring problems occur.

I had a ongoing immobilizer problem; that took me awhile, to figure out and in my case, the speedo cluster was defective, a replacement solved the problem (immobilizer chip reside in the speedo cluster). Having VCDS, is definitely helpful; detailed live data testing, self testing of the speedo cluster, confirming the rfid chip in the key fob, is being "seen" by the immo system, etc, can be done, narrowing down the cause of the problem.

Examples of various measuring blocks; to confirm, status of the immobilizer and components, related to it, working or not.

Ross-Tech: VAG-COM: Immobilizer 3 Measuring Blocks

This can be a challenge, a process of elimination but it can be done.