I installed an LMC5 over a year ago. It has worked fine with an occasional pull key message. I was concerned that if the LMC5 ever stopped working I would still be stranded. So I had the fuel shutoff set to a higher number and had them take care of the skip shift at the same.

Now I feel confident the column lock issue will never leave me stranded and I don't have to put up with that annoying skip shift.

bj1k........if I'm following this right, there must be 3 versions of the LMC5 now.

 

I think someone was counting the ground wire too. On the first version there is only three colored wires ,orange ,purple, and green, then one black ground wire with the bolt loop on the end. On the second version there is four wires and a ground , orange , purple, green, and black , then there is also a black wire for the ground with the bolt loop on the end. I guess it depends if you are counting the ground wire , otherwise there is only the three wire and the four wire versions. There is also a small schematic printed right on the module. Very simple.

 

As 8VETTE7 and others in this string have tried to relate, the first trouble shooting step is to check the battery.

I have the Corvettes of Houston Column Lock Bypass solution just to be safe, but 88% of all these column lock problems are battery related.

Please invest some time and watch the two videos below no matter what kind of battery you currently have or prefer.

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Recommended battery for the C5 is:
AC Delco Professional 78-6YR 700 CCA 120 RC (Part Number 19001632)
Note: 2004 C5 needs 86-6YR 700 CCA 120 RC

Both batteries have 30 month guarantees of free replacement

(GM/Chevy Dealers will try to sell you the cheaper version of this battery with a better margin for them. The cheaper ones have a carrying handle and a different part number.)
........................................ ........................................ ..............

These battery specs are critical to how the C5 electrical system functions BEFORE you start the car. Successfully starting the car is not the important issue. That is secondary. What matters is what happens in the first seconds after the ignition key is inserted and switched ON before the start is initiated.

An annual battery test should yield minimum 12.5 volts and 500 CCA … this test is CRITICAL for C5 Vettes and avoiding column lock issues and other electrical problems.

Also it is recommended to never remove positive lead, remove negative lead anytime car will sit for 30+ days. On reinstall torque to 11 lbs.

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Paul Koerner, World Class GM Technician, @ Carlisle Seminars on C5 Column Lock Issues, Electrical Issues and the Right Battery

Part 1: World Class Technician, Paul Koerner, discusses C5 Column Lock Seminar

http://www.vettetube.com/view_video....e=&category=mr

Part 2: World Class Technician, Paul Koerner, discusses C5 Column Lock Seminar Part 2

http://www.vettetube.com/view_video....e=&category=mr

 

Thank you and 8VETTE7, I thought I read that somewhere - thanks for the correction.

 

I went to the AC Delco website and the part number 19001632 was not a valid PN and the 78 6 yr spec sheet says, 12 Volt Auto & Lt Trk Battery, Group 78, 675 CCA, 110 RC, w/ Side Term - Threaded Insert, Skid Qty = 66. The next one is a 78-7YR 12 Volt Auto & Lt Trk Battery, Group 78, 770 CCA, 120 RC, w/ Side Term - Threaded Insert, Skid Qty = 66. None are 700 CCA and 120. Will the 78-7yr fit in a 2002 coupe?

 

First off, if it is a group 78 it should fit. Here's an update from Paul Koerner about batteries. He posted this information last week.

 

Thanks for the update

By any chance, did Paul specify a new part number for a specific 78PS Battery?

The best I could get out of the AC Delco website Tonight was that a 75 5 yr battery with side posts is the correct battery for a 1997-2002 Corvette. In my experience, AC Delco & Chevrolet parts catalogs & Chevrolet Dealer Parts Departments NEVER recommend the correct battery.

 

No, he doesn't give a part number other than 78PS. He's a Chevrolet Dealer technician so I assume that is the Chevrolet part number. If you go to a Chevy dealer they should either have that one in stock or can get it for you.

 

Thanks for the gouge.

 

All of you know my dilemma on the SCL pull key message. Installed the LMC5 then the LMC5R and still got the PK message. Installed the LMC5 5 wire. Pretty easy so far so good. No pull key message.

 

What do you mean by 5 wire ? Are you counting the black ground wire with the bolt loop as one of the 5 wires ? There would be orange , purple, green, one black connector that plugs into the pink plug and one black ground wire with bolt loop that grounds to the bottom of the BCM. Anyway just glad it fixed it for you.

 

I took my 2002 Corvette to the dealership in September 2012 to fix both these issues. They replaced the relay and charged me $538.61. $49.11 for the part and $489.50 for labor. Unfortunately I had to leave the car parked for awhile and the battery died. I charged the battery and tried to start the car and the pull key message came up, then the service column lock came up. I had to have it taken back to the dealer by flatbed thinking they would correct the problem. I was told they actually disconnected something that would stop the pull key wait 10 sec message. (which I had to take the car back in for them to do since it came on as I was driving down the street from the dealer). I received a phone call from the dealer stating that it was the motor now so it is a different problem and was probably brought about by the battery dying and that it would be $1,000 to repair!! Now my dilemma is that the car is at the dealership and I have to have it towed back if I don't have them fix it. If I buy column lock bypass that I have seen people suggesting can I install it at this point??

I can't afford to pay the $1,000 right now to have it repaired. I have been dealing with this problem for awhile and am thoroughly disgusted. Can anyone suggest the best route to take at this point? I would appreciate any suggestions. Thanks!!

 

The dealer will do nothing but take your money. 8vette7 is the man where column lock problems are concerned. He has helped many people on the forum and has saved them no telling how much money. I feel sure a clb or Lmc5 will cure your problem. My only experience is dealing with it BEFORE it malfunctions. Just don't let the dealer do any more to it. GM does not have a permanent fix.

 

The 5 wire has two black wires. The other black wire goes into the and replaces a dark green wire. All of the other wires go where the original wires went with the original LMC5. 5 days now and no PK message. Yaaaaa hooooooo