I bought my C5 last year.

The column lock recall had been addressed by the previous owner and a semi-local dealer.
Up until today, I have never had the column lock, it would turn without the key.
Now it won't unlock!

Just a few days ago, a local shop turned off the F45 mag ride shock option after I installed Bilsteins.
This of course meant the program in the BCM was changed.

Could the problem with the column be related?

I will trickle charge over night, disconnect the battery for a couple minutes in the morning to reset everything.
I will also check fuse 25 in passenger foot well.

Any other ideas, besides shake, shake, shake?

Is removing the lock plate and a CLB the only way to put this issue to rest?

FRUSTRATED as HELL. Roy

PS. I ordered the LMC5 device from Compliance Parts along with the unlock tool.

PPS. I spent hours last night trying to get through the sticky on this subject. Just my 2 cents, but

There should be a cleaner and easier to understand resource for folks with this issue.
The sticky has been cluttered up with tons of replies, and it is real hard to tell what is fact.
It should be broken into 2 different sections, one for manual transmission cars,
and one specifically for automatic transmission equipped cars.
It should also be titled a "Must Read for new C5 Owners !!! "

 

the people that manufacture the LMC5 also have an unlock tool that you can use to unlock the column

 

The LMC5 should be your solution. I just went ahead and did the brown wire mod on mine as I was installing it. No problem since.

 

When mine locked up, it wouldn't unlock with the unlocker. Richard at compliance parts said to loosen/remove the steering column shroud (not real easy) and tap on the lock with a screwdriver and hammer. That worked.

 

Back in 2003 when I bought my 1999 C5 I experienced the dreaded column lock failure because the original batter had died. The IDIOTS at GM couldn't have anticipated this problem, right? I heard that the column lock was known to deploy WHILE DRIVING CAUSING CRASHES & I would not allow that to happen to me so I put in a jumper to defeat the column lock, so it would never be able to lock the column. It was located on the passenger side floor under the dash. I have kept my battery charged and never had a problem until now. I have a "Service Steering Column Lock" on the dash read out, a check gauges red idiot light on, a empty reading on the fuel gauge with a full tank and a low fuel warning on the display. NO trouble codes. I'm disconnecting he battery to reboot the computers but don't expect this to correct the problem. Does anybody have any suggestions?

 

Could very well be pitted contacts on the Ignition switch contact block which are known to cause this kind of problems. The lack of any codes rule out the serial data network as the culprit.