Cscokd

Ok, it appears now that there's a whole new wave of column lock issues again most likely because C5 owners are selling their cars and we have a new generation of first-time owners of used C5 corvettes.

What makes things worse this time around is that new owners don't know what mods have been done by the previous owner(s) and in some cases by GM. And now GM no longer supports these owners. So this will be my attempt to help you new owners diagnose what exactly you have just purchased with regard to the column lock situation.

Normally I would say to first check with the dealer to discover what GM recall mods were performed by the dealer, but it seems moot now because many previous owners have made their own mods post GM recall mods, so the dealer information cannot be strictly relied upon by a new C5 owner. So let's begin with some FAQs that I seem to get on a daily basis...

When I insert my key, I still hear the column-lock motor make a noise. Does that mean I don't have the K Harness?
No. It means you either have a stock configuration without the GM K Harness mod, or you have a K Harness. It also means you do not have a CLB installed.
When I drive my car, I hear a strange clicking noise when I turn my steering wheel. What does that mean?
This is likely a situation where the column lock motor lock pin is partially extended and rubbing on your lock plate. Since we don't know if the lock plate has been removed, you should check this out BEFORE driving your car again. This could be a life threatening condition should the lock pin engage the lock plate while you're driving!
I get the Column Lock Error and can't drive my car above 2 mph
This is the most common complaint and usually happens right after your battery has discharged or failed. What can we say about this condition? Well, we know the PCM has been reprogrammed to shut off your fuel when you get a Service Column Lock error. Can you turn your steering wheel? If not, we know your lock plate has NOT been removed, we also know your column lock motor is wired into the system, so you DO NOT have a CLB installed. So either you have a stock configuration or you have the K Harness installed. If you CAN turn your steering wheel, it means 1) your column lock motor has failed with the pin retracted, 2) your lock plate has been removed 3) your column lock motor harness has been disconnected. What should I do? Install a CLB.
How can I tell whether I have a K Harness installed or a CLB?
Can you hear the column-lock motor activate when you insert your key? If yes, then you DO NOT have a CLB. If you cannot hear the column-lock motor activate, there’s no conclusive proof because the column lock motor could be in a failed condition, disconnected or a CLB installed. The only sure way to know is to remove the knee bolster and inspect your wiring harness. Locate the connector to your steering column and follow it to the source. The K Harness will have a "Y" wiring configuration with 4 wires going to a GM relay tie wrapped to the left of the steering column and 2 wires going up to the steering column lock motor. A CLB will NOT have any fork in the wiring and the steering column lock motor harness will be disconnected completely.
I installed a CLB and I still get the Service Column Lock error. Why didn’t this fix the problem?
There are several possibilities. Usually the CLB fixes the problem, but not always. Here are a few things to look for:

1. Is your battery fully charged?
2. Did you install your CLB correctly? Some folks not realizing they already have a K Harness installed, locate the wiring harness going up into to the steering column and plug their CLB into this connector which does nothing but disconnect the column lock motor leaving the K Harness still in the circuit. Locate the K Harness and completely remove it. Then connect your CLB per instructions.
3. Sometimes while troubleshooting and working under the dash, you accidentally short out something and pop a fuse. Ensure fuse 23 in the passenger footwell is good. This fuse powers the BCM column-lock motor circuits.
4. If you installed your CLB correctly and fuses are all good, but still get the Service Column Lock error the next step is to determine if you have a secondary GM relay mod (Procedure 1B of the GM recall bulletin). There are two ways to tell: 1) the 4-pin connector where your CLB plugs into will have white, purple, green, black wires or 2) there will be two relays located just above your BCM. The one on the upper rightmost side will be the one to look at. You'll see purple, white, orange, orange, dark green wires coming from it. NO purple wire? Then you don't have the this mod implemented. If you do have this relay mod, the relay could have failed completely or may be causing switching spikes on the 12V line that triggers your CLB to change states immediately after it switched to the correct state thus defeating the CLB operation. The procedure here is a little complicated for those non-electrical types, but the goal is to remove and discard this relay and then jumper between the orange wire (pin 87) and the white wire (pin 30). Note there are two orange wires, so get the correct one! This operation often ends up with a blown fuse 23, so check it before you finish. Email me for photos and instructions if you need them.
5. So none of the above steps have fixed the problem, what now? This is a difficult spot to be in because it only leaves physical wiring faults and the BCM itself. On a few C5s we've found that water got into the passenger footwell and corroded contacts and connector pins. If this happened to you, it's a whole different ballgame to troubleshoot. Personally I’ve never seen a BCM fail in all the years I’ve been helping forum members, so my first suspicion is always fuses, wiring, connector issues or miswire in step #4.

I'm so frustrated I'm ready to drive my car off a cliff. Now what should I do?
Give it to me. I'll gladly pay for the shipping. ha ha

I will add more as time allows, but I hope this is useful information for the forum members.
John (cscokd@gmail.com)

itzza427

Well done,,kinda brings back some bad memories !!! The only thing I ran into,,pulling just 1 fuse didn't do it for mine. After studying the fuse cover diagram ,,there are 3 BCM fuses,,,pulled all three,,let her sit. put them back THEN she worked. Thought it MIGHT help too. Again great write up,,,you have more patience than I do(probably type a lot better than I do too)!!

John Galt

After having worked this issue on my car several times, I think I have found the very best solution. Get the lock removed so your wheel will never lock again, then get someone to use HP Tuner to set the column lock to not installed and disable the fuel cutoff.

I think that is the best and most conclusive solution to this issue.

ljthe2nd

That sounds like the cheapest way to address the problem but couldn't you just get one of the CLB harnesses that the vendors sell to take care of the problem. (I haven't really followed this problem to close because I have an 04, car with the A4 trans so this doesn't affect my car, so I could be wrong)

Cscokd

I understand what you're saying except you'll have a Service Column Lock message on your DIC to reset everytime you want to see anything on your DIC.

The very best solution is to remove the lock plate, install the CLB and reprogram your PCM with HP Tuner to eliminate the fuel cutoff. At least that way you'll never be stranded if/when you get a Service Column Lock error.

I designed and installed my own CLB years ago and I've not had one error message...period. That includes several low battery conditions over the years. When you get it right, it WILL be reliable.

bluvette79

thanks csco. good write up for all of those in need of some definitive advice regarding the cbl. you get 6 attaboys

mrkzoo

Good write up! Once the 6" of snow outside that we got last night melts I can start working on the problem.

Thanks
Tim

02impactblue

What does the "K" harness do? When I bought the car it had the column lock recall done but from what I understand there were several versions of the recall. I think I just have the ecm reprogram but not sure. I guess I need the clb to be sure I'm covered.

Cscokd

first things first, check and see what you have installed before you buy anything

TEXHAWK0

The above guide is very good in determining what to check, especially if you are getting an error message.

If you are not having problems, you still need to determine 1. if you still hear the actuator cycle when the key is turned (if so, then you could have the Harness K kit installed or it could still be stock with no relay) 2. if you hear the actuator cycle, and the column does not lock, then you probably have the Harness K kit installed and the lockplate has been removed.

One way to know for sure what you have is to pull the panel below the steering column and 1. see if the actuator connection is still connected to the stock harness, 2. the actuator has been disconnected and a relay is connected to the factory wiring harness with the actuator left disconnected , or 3. the Harness K relay harness has been connected in between the main wiring harness and the actuator. (the actuator is still in the circuit, and will cycle when the key is turned)

John Galt

You can, but, if the CLB fails (and they do fail), you will still be stuck because of the fuel cutoff...you need to get that programmed out with HP Tuner.

seawolf

Great, and very helpful, post. One question I still have. My 02 has had all the updates done by GM. I know to get the fuel shut off programed out but what exactly do I have to do now to install the CLB. That is still confusing to me with the information I have read. Thanks.

bluvette79

i bought mine from corvettes of houston and it came with instructions. there are several instruction threads on this forum - here is the one i used along with the instructions from houston:

http://www.ls1howto.com/index.php?article=24

you can also do a search on this forum or review the stickey as i believe it has instructions as well.

Bill Curlee

Does EFI Live have the same fuel shut off programing capability as HP Tuners????

ROCKnROLL

TTT