I finally got around to installing the LMC5 module, so far all is well.

My car is a 98, mid December build. When I got my oil changed, they let me look under the car to see where the ECBM is located. Mine has the rear mounted version, so it is an 'early' 98.

I called Richard before starting to clarify a few things I read here.

I read that there is a slightly different lmc5 module for early C5s. According to Richard, there are 2 versions of the BCM. Version 1 is on all C5s built approximately before Feb 1998. From Feb 1998 through March 1998 it may have either version 1 or version 2. After March 1998 should all be version 2.

Mine should have the version 1 BCM.

He has found that with a very small number of version 1 BCMs, you may get the "pull key wait 10 sec" message. The 'other' lmc5 module fixes this. He said if I see the message, call him.

I also asked about the optional brown wire mod, and if I should just do it. He said no, it has no effect on a version 1 BCM, it is only effective on the version 2 BCM.

Even though some version (I don't know which) of the recall was performed, mine still locked. So I had to do the fuse 23 part. I recommend having a pair of needle nose pliers handy for pulling the fuse.

When disconnecting the neg terminal on the battery, I heard some clicking which I assume was relays somewhere. I found that a bit disconcerting.

I had some trouble getting the orange wire out of the green connector. I called Richard, he suggested several things which didn't work. Finally he said to try plan B, which was to get a good grip on the wire and firmly pull it out (don't yank). That worked. The purple and green wires went much easier.

I don't have a column lock relay to pull.

Put everything back in, reconnected the battery (more clicking), and went through the described test procedure. The column did not lock, and no 'pull key' messages. All appeared to be well.

I took the car out for a spin, everything was good. I noticed it was estimating only 160 mile range for my full tank of gas, which finally crept up to about 420 after some driving around.

Got home, and when I tried to lock the car the fobs didn't work. Retraining fixed that.

During the test drive, I got my usual 'service vehicle soon' message, which I have been ignoring.

After getting home, I pulled the codes before shutting off the engine. In addition to the TCS C1281, I also had a TCS C1255 H (history, not current) which is a bit worrisome. I haven't seen that before. I also had a few other codes. I'm hoping the extra codes are due to the battery being disconnected. I cleared them all will see if they come back.

I still need to reset the clock, not sure if there is anything else that needs to be reset. The theftloc on the stereo was never activated, so didn't need to do anything with it.

 

Nice report... glad things are going smoothly...

I feel your pain with the wire NOT releasing... I tried a drill bit, a larger alan wrench, I push, I pulled, I twisted, cussed, fumed... and finally called Richard and just pulled the dang thing out...after about thirty minutes of wrestling with it... and it was the LAST wire... just couldn't figure out what I was doing different or wrong..lol

 

I went for another long test drive, the only code that reappeared is the TCS 1281, along with the 'service vehicle soon' message. This is a common code for this car that has been going on since the car was new. The dealer was never able to figure out why. Other than the message, it has had no effect on the car, so is just a minor irritant.

I need to figure out how to turn off the 'ding' when the messages appears, before it was silent.

So far, all is well.

 

 

https://www.corvetteforum.com/forums...hat-is-it.html

 

Is there a method for determine if magnasteer is functioning? Should clearing the code re-enable it? I can't tell any difference before and after message appears.

This is the only corvette I have ever driven, so you are correct that it may not be working and I don't know the difference.

It doesn't feel twitchy at highway speed. Not sure if this is in any way comparable, but my 97 Tahoe has variable assist - not magnasteer, but by varying an oriface in the hydraulic system to change pressure. The level of assist in the corvette feels better than the Tahoe.

The corvette steering does feel a bit numb. I was expecting better, but I have gotten used to it.

 

In our car you can definitely tell when your cornering at higher speeds the steering is much tighter... or going down the hiway at 75 you can feel that is the steering is heavier...
this link may have the info you need...

https://www.corvetteforum.com/forums...r-failing.html

 

My steering doesn't feel loose like that link describes. There is no play in the steering and it doesn't feel like it is too light in the corners, although I don't do high speed corners much.

I just bought a Mercedes GLK a few months back. It has electric steering, the corvette is a little heavier but similar feel.

That link implies that if the ECBM fails, it takes magnasteer with it. That is new to me, I thought it only affected ABS and traction control. I don't have active handling.

 

 

I had the car at the dealer this morning to recharge the A/C, and asked them about the 1281 code if there was a way determine if magnasteer is actually working.

I had already cleared the code out, so they didn't find any problems. They did say that it was working normally, but I don't know if they know for sure it is working, or just assuming it is because there was no code.

If there are no codes in the system, then magnasteer should be working on the next ignition cycle? If that is the case, then I don't think the code is disabling it. I normally clear the code when I stop the car, so it is clear on the next restart. while driving down the road, the message intermittently appears, but the feel of the steering doesn't change. From this, it sounds like I should continue ignoring it.

They didn't do the seatbelt recall, they didn't have the parts. Don't know why they didn't check and order the parts when I was in last week and made the appointment...

LMC5 seems to be ok, I have not had any weird problems or 'pull key' messages.

 

The code doesn't disable anything bud, it just reports that there is a problem some where in a certain module BCM, PCM, etc.. and is reporting it to you via the DIC... I would just ignore it and enjoy the ride brother

 

So I went for another test drive last night, about 10:30, so it was dark out. TCS 1281 popped up again. I wasn't on a curvy road, so the steering didn't feel like it changed. I wish it would happen on a road with turns so I could really determine if magnasteer is going out.

I never really drove much at night before, but went away with a couple points:

Summer night, clear dark sky, away from the light pollution of the city, with the top down, is pretty awesome. Cruising down the road and able to see all the stars and moon is a lot of fun.

The lowbeams suck. I didn't realize how bad until I saw that you are almost through a turn on an unlit road before you see it. The high beams are much better.

Want the thrill of doing 100 mph without the risk of going to jail? Drive down a dark unlit road with the lowbeams. Felt like I was really flying, only to look down and see I was barely doing the speed limit.

 

I did find a used SWPS, and did confirm with the dealer that I have the correct part number. So I have that available if I determine that I have a real problem.

 

After some reading, I found a thread that suggests that c1281 codes can be caused by the connection between the SWPS and the EBCM. I'm beginning to suspect that may be the issue, sometimes I get the SVS message after hitting a bump.

I can't do anything about it now, I will going out of town, so the car goes back to sleep on the battery tender.