LMC5 Failure?/ Service Column Lock Code
Thread Starter
Instructor
Joined: Feb 2014
Posts: 123
Likes: 70
LMC5 Failure?/ Service Column Lock Code
Hey guys my daily driver C5Z is acting up. Starting this week I started getting a service Column Lock error. I have also Noticed that when I turn the key off I do not hear the clicking from the bcm area of what I am guessing the LMC5 doing its work. I have also noticed that at the same time that when I go to start the car I can turn the key to start the starter will click like a bad solenoid. However before I let the key go you might hear another click or the starter engage. Seeing that the lmc5 says to look at the key switch I removed it from the car and put in a brand new ac delco unit. Bad news on that front as the new ignition switch would not crank the car over at all. Thank you made in china garbage. I took apart the old switch and the contacts were gross. I cleaned them up and put the old unit back in. I cleared the bcm and everything looked good. However on startup the starter clicked five times while holding the key in start. So I guess I will order another new switch while at work tomorrow. Thinking the switch could still be bad.
Anybody have their LMC5 Fail. The previous owner put the unit in. I saw it when I got power for my radio. Car still drives but I do not want to risk it dying on me so going to park the car till I figure this out.
Anything else I should look at it?
Anybody have their LMC5 Fail. The previous owner put the unit in. I saw it when I got power for my radio. Car still drives but I do not want to risk it dying on me so going to park the car till I figure this out.
Anything else I should look at it?
Thread Starter
Instructor
Joined: Feb 2014
Posts: 123
Likes: 70
Might order a new module. It went in late 2017. Battery is a brand new AGM unit that went in January 22. 12.3 volts on the display after 1 hour of light on work in the car. I had got some error codes before when the old battery died.
Safety Car
Joined: Dec 2011
Posts: 4,704
Likes: 239
From: Redondo Beach CA
If you get stuck, you can always furiously pound and jerk the steering wheel in frustration until if frees up. of course, not something a reasonable man would include in his travel plans, but good to know. if for no other reason that to explain why you are pounding on your stuck steering wheel like a mad man all of a sudden, just pretend it is a logical response.
Drifting
Joined: May 2020
Posts: 1,663
Likes: 702
From: Baton Rouge, Louisiana, metro area
Call Richard at Compliance Automotive.
I have talked to him numerous times on both the LMC5 and VATS bypass for my 99.
He is very helpful and knowledgeable.
He can likely help you troubleshoot.
http://www.complianceparts.com/contactus.html
I have talked to him numerous times on both the LMC5 and VATS bypass for my 99.
He is very helpful and knowledgeable.
He can likely help you troubleshoot.
http://www.complianceparts.com/contactus.html
Administrator
Joined: Mar 2001
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From: In a parallel universe. Currently own 2014 Stingray Coupe.
C7 of the Year - Modified Finalist 2021
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St. Jude Donor '03 thru '26
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Moved to C5 Tech.
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Safety Car
Joined: Sep 2000
Posts: 3,572
Likes: 420
From: Taildragers rule! USA1
I'd dump the LMC-5 for the old fashioned CLB
https://www.ebay.com/itm/11442726933...oAAOSwn25aGE~H
These are just WAY simpler, you never have to "call Richard" and never have to do the "brown wire mod."
https://www.ebay.com/itm/11442726933...oAAOSwn25aGE~H
These are just WAY simpler, you never have to "call Richard" and never have to do the "brown wire mod."
Drifting
Joined: Jun 2006
Posts: 1,444
Likes: 401
From: Palm City
St. Jude Donor '06-'11
How old is the battery? Very slight voltage drops cause lots of weird issues with these cars. A new battery has solved lots of issues for me with C5’s and C6’s over the years.
Thread Starter
Instructor
Joined: Feb 2014
Posts: 123
Likes: 70
So went out today and played with some more. Fixed the new switch as it was not making contact. Still error codes. Figured it was not a switch problem. Decided to reset the bcm and pulled both bolts....well negative screwed out like normal. The positive fell out. Raided spare bolt I kept from junking a car a few months back and installed it. Well boom everything works. Starter clicking is gone, error messages are gone, starter is much stronger and my jumping voltage on the gauge has smoothed out to were it was when I bought the car. So seems it is fixed. All this over a one bad battery bolt.
