Originally Posted by 8VETTE7

Couple of items in your post. The NHTSA recall did NOT start until Jan. 2004. So any work that GM did to the car back in 2002 was done as a part of the predacessor program to the actual recall. GM had a CSP 01004 that they were using and trying to avoid the recall. It did some of the same steps that were actually done under the recall but the program was NOT implemented uniformly and the exact work done to your car under it, if the actual recall was not done again after Jan 2004, is questionable at best. Get a copy of the GMVIS and see if there was a later service done to the column lock system.

The removing or actual bypassing of the "spliced purple wire and relay mod" is only done to 99 and 2000 manual trans cars that the owner want to install a CLB. Just bypassing the relay with the jumper wire DOES NOT correct the Column Lock symptoms unless you are installing a CLB.

Here is a link to a thread that speaks in detail to the bypassing of the column lock relay in 99 and 2000 manual trans cars:

http://Forums.corvetteforum.com/c5-t...installed.html

Scroll down to about post 13 and begin reading. The detail pictures in my post #15 in that thread were not available when I looked at it just moments ago because the site hosting the pictures was having problems. Hopefully the site will be back operational soon. You may have to try again later today or tomorrow to see those pictures.

There is a potential negative impact to the BCM if you do the bypass and DO NOT install a CLB. Namely the BCM is directly driving the column lock motor and it is possible to fry the column lock circuits in the BCM if the battery goes low when this mod is done.

And yes the jumper is a permanent step in that the relay head is NOT reinstalled.

If you are having column lock symptoms on your 99, I recommend that you install the LMC5 rather than a CLB. It does NOT require the bypassing of the Column Lock Relay and is IMHO a better solution at least for 99 and 2000 manual trans cars.

Lastly the MOST likely cause of the symptoms you are seeing is a weak or bad battery or loose or corroded battery connections including the one at the starter. I strongly suggest that you have the battery tested. The voltage across the battery posts with nothing else connected to the battery MUST be greater than 12.5 volts. If it is NOT greater than 12.5 volts then the electronics in the car will NOT function properly. This is particularly true of the column lock electronics. The car will start with 12.2 volts or less but the Column Lock Electronics will fail to function correctly. Having voltage after the car starts from the alternator does NOT help. That is because the column lock electronics does its thing BEFORE the engine starts. Voltage once the car starts is Too late to help. Try recharging the battery to full charge. A good battery at full charge will measure 12.7 to 12.9 volts or more. If you cannot charge the battery to at least 12.7 volts it is on its way out and needs to be replaced.

Originally Posted by 8VETTE7

CLB = Column Lock Bypass. It's a device that plugs into the wiring under the drivers knee bolster in place of the lock motor connection. The column gets unlocked, then you unplug the lock motor connector that goes to the BCM and plug in the CLB connector in its place. The lock motor will never operate again so the column is permanently unlocked even with no key in the ignition. The CLB is installed to accept the lock or unlock command from the BCM and then respond back to the BCM with the required "completed" signal to let the BCM "think" that the column was locked or unlocked as commanded. Without the appropriate "completed" signal the BCM thinks there is a problem with the column lock system and if it thinks the column is locked when it should be unlocked, the BCM commands the PCM to enable fuel shutoff. The PCM then shuts the fuel off at the defined speed. The Recall service set the speed to 2mph. It is possible to set the speed to a high number with the proper tuning software (HP Tuners or EFI Live). With the lock motor disconnected when the column was unlocked you can never get stranded by a locked column, only by the fuel shutoff unless that is reprogrammed. One of the benefits of a CLB is that it is much more reliable (if properly installed) than the lock motor was at responding to the BCM commands so that you are FAR less likely to experience a fuel shutoff if you don't reprogram the fuel shutoff speed. MOST people that install a CLB do NOT have the shutoff speed reprogrammed and very, very few ever have fuel shutoff issues. Properly installed means removing the GM K Harness if one was installed and for 99 and 2000 manual trans cars, bypassing the Column Lock relay if the spliced purple wire and relay mod was don as a part of the recall service.


LMC5 = Lock Module C5. It is a fairly new approach (last 2 years) to bypassing the lock motor. Rather than leaving car wiring between the BCM and the CLB, the LMC5 connects directly to the BCM. It does much of the same process, namely responding to the BCM when lock or unlock commands are issued by the BCM. It is claimed to be simpler to install than a CLB and given the unknowns of what may have been done by the dealer Techs or previous owners to the column lock system, it probably is. For a CLB to be properly installed you MUST disconnect the GM K Harness that MAY have been installed before plugging in the CLB. For a CLB on 99 and 2000 manual trans C5's you also need to bypass the Column Lock Relay. For the LMC5. since you disconnect and reconnect wires right at the BCM you don't need to know what may have been done by GM Techs or previous owners as the car wiring is left intact but disconnected. The down side if there is one to the LMC5 is that there are 3 different variations to the product, LMC5, LMC5-R and 5 wire LMC5. Apparently this is necessary because some C5's do not respond 100% correctly to the base LMC5 that everyone starts with. Some C5 with the base LMC5 installed continue to get the "Pull key..." message when they start the car. The good news is that the vendor is very good to work with. Call them and explain your issues and after insuring you correctly installed the product they send you the LMC5-R to try. If that still doesn't work, call back and you will get the 5 wire LMC5. I have not heard of any cases where the 3rd product doesn't completely bypass the column lock system.

The 99 and 2000 manual trans cars are the worst to deal with on Column Lock problems but even those can be made to work with either a CLB or LMC5.

Without one of these two aftermarket solutions it is just a matter of time untill a C5 that can experience the column lock symptoms does experience them. Worst is when the car is NOT close to home where you can work on the issue without getting taken by a Stealership. GM has NEVER had a permanent fix for the C5 column lock symptoms and anything a stealership does for repairs to the column lock system WILL fail again.

Originally Posted by mayajpm

I have the LMC5 on order. It should show up in a day or so. I will let you know how it goes once I install it.

Originally Posted by 8VETTE7

Call or email Compliance, the maker of the LMC5. Google Compliance parts for email address and phone info.

Originally Posted by 1998BlackPlasticToy

Ok. Thanks!! I'll call tomorrow.

Originally Posted by bjones7131

Contact the guys u got lmc5 from, they r good n fixing your problem, i got one ordered and my cl is working fine, but who knows when it will lock.

Originally Posted by vette girl 1953

I have a 2000 corvette stick shift. My steering wheel locked up and spoke with dealer and he said I can tow to dealer OR try to disconnect battery and touch the cables together and hook back up and see if the computer resets...any ideas ?

Originally Posted by bjones7131

Order the lmc5 device, have it overnight shipped, 40.00 plus shipping. I installed it on mine lsat week. Pretty easy to install. Search for the youtube on it.