Howdy all,

So, I decided to install an LMC5 from Compliance Parts as a bit of preventative maintenance on the ‘01 Z. I did the install on my old ‘02 Z without any issues. However, this time around I’m a bit stumped. I followed the instructions per my situation (no column lock messages or pull key messages on the DIC), and got everything installed with no real issues (other than destroying one of the 20 year old brittle blue retention clips for the harness on the BCM...photo below). Once the module was installed, I went to turn the ignition to “on” to make sure I didn’t have any nasty messages on the DIC. None! Perfect, so I go to crank the car over and...nothing. I try one more time and even more nothing. As in, now I have zero power going to anything. When the key is in the “on” position, I have no power lighting up gauges, DIC, center console, etc.

Looking at Compliance Parts’ LCM5 trouble shooting page, I go through all of the fuses that have anything to do with the BCM. They are all good; none are blown. I thought perhaps my battery wasn’t as good as I thought, so overnight I put it back on the CTEK to charge/recondition the battery. This morning the CTEK shows everything is dressed-right-dress on the battery, so I go to crank the engine...and again; nothing. No power going to anything.

I realize Richard from Compliance Parts is very helpful, however, it is Sunday and I know he needs time off just like anyone else. Before I start calling him tomorrow, can you guys offer up any possible solutions? I’m certain there is some random fuse somewhere that I am not checking. And the negative cable for the battery is securely reinstalled. Maybe the blue retention clip on the green BCM harness is the culprit? Anyone know of where a replacement one can be purchased?


The remains of the blue retention clip...

I’m open to any suggestions and thank you in advance!

 

One other bit of information; I uninstalled the LMC5 thinking perhaps it was the module itself, but I still have zero power going to the car. So, I’m almost certain it is a fuse somewhere. Yet, all the BCM fuses are good.

Out in the garage checking fuses...

 

Do you have any interior or parking lights?

 

No. None at all.

 

fuse 25, 23 13 & 9 are used for the BCM I would check those first
Do you have a meter or test light

 

Checked all of those already and they were all good. I will go back and check again. I have both a test light and meter.

 

If you turn the key to ON what does the battery voltage read across the battery terminals?

 

fuse 25 & 23 should have power at all times, you could pull the fuse and check that there is 12v at the socket or if you can sometimes probe the top of the fuse with it in place

 

10-4. Standby and I will go check. I appreciate your help with this.

 

10.66v across the terminals.

But here is something else weird, when I first touched the hot side of the battery, the car “came alive.” The interior lights came on. So, I hopped in to try and start it, had the courtesy tone when I put the key in, gauges were alive. Turned the ignition to start...and...nothing. Now everything is dead again.

 

No joy at fuses 25 & 23.

 

If it were me, next I would pull the battery out and bring it to an auto parts store and let them load test it. Most of them will be able to do this for you.

 

My thoughts exactly. Weird that it did this with the installation of the LMC5 though. Car was operating perfect prior to this. Could the installation cause a rapid draw on the battery? I know C5s are very sensitive to battery issues though.

Off to the auto parts store...

Thank you again for your help.

 

Take a good look at your battery cables while you're in there. You should probably still read some voltage at fuses 25 & 23, even if it's below 12v and too weak to run your car

 

So, here’s what I love about cars. Right when you have the confidence to think you know what you’re doing, you’ll be shown the error of your ways. Lol.

I go to pull the battery and the negative cable is nice and secure. Remove it and move to the positive side. Barely half a turn of the box-end wrench and it falls right off. Hmmm. Re-secure it and re-secure the negative; car comes alive.

Fires right up.

How many beers do I owe you Old School?

 

 

LMC5 re-installed and the CAGS-SKIP module installed. Z is still alive!

This is a good lesson in not jumping to conclusions about what the problem might be. With the information I had at-hand, I was sure the LMC5 was at fault. However, once I discovered the positive battery cable was loose, obviously the problem was the guy behind the wrenches.

Thanks again Old School for helping me take a second objective look at everything!

 

I had a similar problem with the side mount battery terminals on my Buick. Long story short, the positive cable bolt wouldn’t snug tight. Ended up replacing the terminal bolt for one with more threads.

 

I agree, load test the battery. But it sounds more like a connection issue! Clean the terminals and cable ends with a wire brush. Or if you don't have that, baking soda and water will dissolve the build up on the terminal from the hydrogen gas. Even if you don't see any, that doesn't mean there isn't any hidden in the threads of the battery or the cable ends if you have a side post. If you have a top post, wire brush or even scrap the posts and inside of the cable ends with the edge of something to clean them and get a good connection. It doesn't take much to stop from getting a good connection. Also makes sure to snug tighten the connections when you test again. A loose connection will cause the same troubles your describing.

 

Nothing like a loose positive battery cable to humble you on a weekend. I’ll hit the terminals with baking soda and vinegar later this week. Snugged up the positive side and got it nice and tight. It all works now much to my wife’s disbelief!