Really stuck on Column Lock - Maybe BCM?
Thread Starter
Intermediate
Joined: Mar 2009
Posts: 37
Likes: 0
From: San Diego CA
Really stuck on Column Lock - Maybe BCM?
My car is a 2002 z06. I have not driven it in several months due to health issues. The battery may have been bad before but went completely dead during this time and would not hold a charge.
I charged the battery once, drove the car to my work, went out to start it again - typical column lock problems.
I had already installed a Corvettes of Houston lock bypass last year when I had column lock issues - this fixed it.
I tried reinstall the bypass - no results. I ordered another bypass and installed it - no results. I tried pulling fuse 25 and 29 (even for 20 minutes) - no result. I tried pulling 23 as well - no results.
My car does not have the K harness installed, but the lockplate is removed. I removed the K harness when I put the CLB in last year. It also does not have the purple splice wire near the BCM.
I also just tried connecting Pin 30 and 87 in the relay above the BCM per instructions on the forums - this didnt change anything. I cleared the codes before turning the car on and it still came back.
Also, if I just hook up my factory harness without the CLB it has "Pull Key, Wait 10 Sec" message, but not the column lock message. Either way it still shuts off over a few mph.
Any suggestions? I solder PCBs as part of what I do for a living so I pulled the BCM and looked at it and nothing looks loose or bad connections. Corvettes of Houston suggested the BCM may be bad and I am not doubting their word, just wondering if there is anything else I should try.
Thanks
I charged the battery once, drove the car to my work, went out to start it again - typical column lock problems.
I had already installed a Corvettes of Houston lock bypass last year when I had column lock issues - this fixed it.
I tried reinstall the bypass - no results. I ordered another bypass and installed it - no results. I tried pulling fuse 25 and 29 (even for 20 minutes) - no result. I tried pulling 23 as well - no results.
My car does not have the K harness installed, but the lockplate is removed. I removed the K harness when I put the CLB in last year. It also does not have the purple splice wire near the BCM.
I also just tried connecting Pin 30 and 87 in the relay above the BCM per instructions on the forums - this didnt change anything. I cleared the codes before turning the car on and it still came back.
Also, if I just hook up my factory harness without the CLB it has "Pull Key, Wait 10 Sec" message, but not the column lock message. Either way it still shuts off over a few mph.
Any suggestions? I solder PCBs as part of what I do for a living so I pulled the BCM and looked at it and nothing looks loose or bad connections. Corvettes of Houston suggested the BCM may be bad and I am not doubting their word, just wondering if there is anything else I should try.
Thanks
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Before you get too deep in replacement parts, Try this:
Measure the voltages on each one of the BCM fuses to ground. Each fuse has TWO test points on top of the fuse. Make sure that the ignition switch is ON. You should see FULL battery voltage on each fuse. If it reads less,, thats an issue.
Post what you read.
BC
Measure the voltages on each one of the BCM fuses to ground. Each fuse has TWO test points on top of the fuse. Make sure that the ignition switch is ON. You should see FULL battery voltage on each fuse. If it reads less,, thats an issue.
Post what you read.
BC
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Once you check the fuses,, examine the schematic below:
If you apply 12 VDC directly to the Column Lock with the harness that came with the CLB, does the column lock motor move?
Its important to know if the Column Lock Moror works. If you reverse polarity on that Corvettes of Houston Harness that you have it should work in either direction freely.
I would also change the Steering Colume Lock Relay if you have not already.
If you apply 12 VDC directly to the Column Lock with the harness that came with the CLB, does the column lock motor move?
Its important to know if the Column Lock Moror works. If you reverse polarity on that Corvettes of Houston Harness that you have it should work in either direction freely.
I would also change the Steering Colume Lock Relay if you have not already.
Thread Starter
Intermediate
Joined: Mar 2009
Posts: 37
Likes: 0
From: San Diego CA
Bill, thank you, I will try to check voltages tomorrow since the car is stuck at my office.
The column lock motor does not move when I plug in the harness, but I assumed that was because it was already drawn back (I could always turn the wheel).
I do not know if it is normal or not but when I shut the car on or off the BCM does make a few clicking noises.
The column lock motor does not move when I plug in the harness, but I assumed that was because it was already drawn back (I could always turn the wheel).
I do not know if it is normal or not but when I shut the car on or off the BCM does make a few clicking noises.
Pro
Joined: Oct 2010
Posts: 564
Likes: 12
From: Vancouver British Columbia
Recall 04006c...
Bypassing the Column Lock relay is for the 99 and 2000 model year manual trans cars and NOT the 2001 and later model years.
Remove the jumper you installed if it is still connected.
I agree with Bill C that you should try replacing the column lock relay (the one you tried to bypass unsuccessfully). It's an SPDT relay and you may have to take the old one to the parts store to get one as their parts list doesn't always show the Column Lock relay.
You should also insure that your battery has greater than 12.5 volts measured across the battery posts with the neg battery cable disconnected. (ie NO LOAD voltage) The Column Lock electronics does not work correctly is the battery voltage is not greater than 12.5.
Remove the jumper you installed if it is still connected.
I agree with Bill C that you should try replacing the column lock relay (the one you tried to bypass unsuccessfully). It's an SPDT relay and you may have to take the old one to the parts store to get one as their parts list doesn't always show the Column Lock relay.
You should also insure that your battery has greater than 12.5 volts measured across the battery posts with the neg battery cable disconnected. (ie NO LOAD voltage) The Column Lock electronics does not work correctly is the battery voltage is not greater than 12.5.
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Its difficult to say what GM will honor these days! They will honor a government bailout mandate.
I wonder it the VOLT has a column lock issue??
OH WAIT,, they BURST into flames after an accident!
I wonder it the VOLT has a column lock issue??OH WAIT,, they BURST into flames after an accident!
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!
Michael S. Palmer
10 Revolutionary 'Corvette Firsts' Most People Don't Know
Joe Kucinski
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2
Michael S. Palmer
2027 Corvette vs The World: Every C8 vs Its Closest Competitor
Joe Kucinski
10 Most Common Corvette Problems of the Last 20 Years!
Joe Kucinski
5 MOST and 5 LEAST Popular Corvette Model Years in History!
Joe Kucinski
2027 Corvette Buyer's Guide: Everything You Need to Know!
Joe Kucinski
Thread Starter
Intermediate
Joined: Mar 2009
Posts: 37
Likes: 0
From: San Diego CA
Ended up just getting the LMC5.
I checked the voltages and those were fine. The relay could have been bad but the local auto parts store didnt stock one, and I dont have a lot of spare time. The LMC5 came in the mail, installed in 10 minutes and immediately removed all problems, I didnt even have to clear codes.
I checked the voltages and those were fine. The relay could have been bad but the local auto parts store didnt stock one, and I dont have a lot of spare time. The LMC5 came in the mail, installed in 10 minutes and immediately removed all problems, I didnt even have to clear codes.
Pro
Joined: Oct 2010
Posts: 564
Likes: 12
From: Vancouver British Columbia
Couple of technical details about 04006C column lock service. First it doesn't actually remove the lock plate. They replace the full diameter lock plate with the small diameter lock plate that is used on auto trans C5's. The lock pin cannot intercept that lock plate so the column never physically locks again once it is installed. The lock plate serves as the signal light cancellation cam plus it is required (or a spacer) to stack other things mounted on the column. Second since the PCM was reflashed with a load that sets the fuel shutoff to 2mph by all of the recall services BEFORE 04006C, it's a moot point for your car that 04006C does not call for the 2mph fuel shutoff. They DO NOT reprogram the PCM back to factory with 04006C so your stuck with that unless you pay a tuner to set it to a large number.
The question is whether or not you can get a local dealer to do the service free of charge. It's always worth a try but likely the answer is it depends totally on the local dealer. Extremely unlikely that GM is going to reimburse the dealer if they do the service. So the dealer would have to eat the cost or perhaps split the cost with you. I worked with a Forum member recently that was able to get his dealer to do the 04006C service for $180. (His car already had an earlier 04006 service done so GM would not pick up the tab). $180 is a reasonible cost for the work that has to be done. The column has to be totally dismantled to get to the lock plate, cost of the new lock plate, plus reassembly. Most dealers are getting 2 1/2 hours labor plus parts and shop supplies etc.
Personally I would do the CLB and have the fuel shutoff reprogrammed to a high number by a tuner that has either HP Tuners or EFI Live tuning software and leave it at that. With those two things the worst you are going to have even if the CLB were to fail (it won't) is an error message in the DIC about service column lock. You can never get stranded by either a locked column or by the fuel shutoff. My car has both those things since 4 years ago and although I did have the battery die, I have never been stranded by the column lock system. I personally would not install the LMC5 on my car but that could be an option if you are willing to install it on yours. The manufacturer claims that you do not need the to have the PCM reprogramed if their device is installed.
The question is whether or not you can get a local dealer to do the service free of charge. It's always worth a try but likely the answer is it depends totally on the local dealer. Extremely unlikely that GM is going to reimburse the dealer if they do the service. So the dealer would have to eat the cost or perhaps split the cost with you. I worked with a Forum member recently that was able to get his dealer to do the 04006C service for $180. (His car already had an earlier 04006 service done so GM would not pick up the tab). $180 is a reasonible cost for the work that has to be done. The column has to be totally dismantled to get to the lock plate, cost of the new lock plate, plus reassembly. Most dealers are getting 2 1/2 hours labor plus parts and shop supplies etc.
Personally I would do the CLB and have the fuel shutoff reprogrammed to a high number by a tuner that has either HP Tuners or EFI Live tuning software and leave it at that. With those two things the worst you are going to have even if the CLB were to fail (it won't) is an error message in the DIC about service column lock. You can never get stranded by either a locked column or by the fuel shutoff. My car has both those things since 4 years ago and although I did have the battery die, I have never been stranded by the column lock system. I personally would not install the LMC5 on my car but that could be an option if you are willing to install it on yours. The manufacturer claims that you do not need the to have the PCM reprogramed if their device is installed.
Last edited by tak06; Mar 2, 2012 at 08:21 PM.
Safety Car
Joined: Oct 2011
Posts: 4,831
Likes: 21
From: The Voice of Reason!
St. Jude Donor '14
Ended up just getting the LMC5.
I checked the voltages and those were fine. The relay could have been bad but the local auto parts store didnt stock one, and I dont have a lot of spare time. The LMC5 came in the mail, installed in 10 minutes and immediately removed all problems, I didnt even have to clear codes.
I checked the voltages and those were fine. The relay could have been bad but the local auto parts store didnt stock one, and I dont have a lot of spare time. The LMC5 came in the mail, installed in 10 minutes and immediately removed all problems, I didnt even have to clear codes.
