Cleaned up all earth leads I can find and unplugged cleaned and plugged all connector blocks etc.., Door locks.. Windows.. Radio all work, but no ignition lights? And just get "vehicle protection system not available" alarm?
Loads of listings for this on Google and other forums but no definitive answer?
I had very similar problem in my 159 jtdm. no diagnostics possible etc. fault is is steering lock. problem in my case was that it was not turning enough (overused cog wheels they are plastic). there are 2 microswitches inside (on small PCB plugged into main PCB) one is open one is closed in one position of lock and opposite for other. in my unlucky case, it was basically "reporting" not unlocked state, so didn;t give out necessary signals to allow kick of other supplies and so all seemed like dead. most of cars has issue in oppostite state so they only report fault but ignition works OK.
What I did as very temporary fix was I opened the steering lock mechanism, removed the lock and cog wheels, shorted one of microswitches (don;t ask me which one, can;t remember, but you can figure out based on work on cog wheel which shoudl be pressed), and then car ignition started to work, just at ignition off was reporting vehicle proteciton not available (As expected, since microwitches were forced to report unlocked state).
after a few days I got brand new steering lock module. I was not sure if that does not need to be coded-paired togeteher with immobiliser/keys, so suspecting old lock electronics OK, I swapped my old motherboard to new unit.
One note here, sometime in 2006 they changed polarity of connecotr for electric motor inside this unit. I got new unit with reversed polarity, so I had to swap wires within connector of new motor to match old PCB polarity.
FYI, I was lucky to buy brand new steering lock mechanism for only like EUR30 (stock clearance, it was old part number (actually the same as my 2005 car's but internally had inversed motor connection as mentioend earlier), replaced many times with newer part numbers), but even in dealers brand new/latest rev cost liek EUR250 as far as I know.
DO NOT SCRAP YOUR TI!!! just get repaired this small failure.