Bill Curlee

Try this:









Ground G-104



G-101



G-401 & G-402 Rear drivers and passengers fender well between the rear tire and the fender well.


Ground on the rear of the drivers side cylinder dead. (white/black wires)



Corrosion on the pins inside ground connector g-101





BC

Billdog350

Bill, thanks again for all of your pics and info. I'm also having issues with my 1997 C5 showing about .5 to 1 volt lower at the DIC vs the battery. I'm planning on ripping into every ground and seeing what's up. I'd REALLY like to get the DIC as close to the true voltage as possible, as well as provide enough ground so my various sensors don't lose power when I start up. Once your grounds were fixed, did you notice if the DIC matched a volt meter @ the battery?

Bill Curlee

On most C5, the DIC voltage level is lower than the actual battery voltage level. Some are worse than others. I will have to go out and see what my difference is.


Bill

cebars

Bill:

Thanks for the valuable information which I and many others will be able to put to good use. The time, money and aggravation saved will be substantial.

Bill Curlee

TTT

BC

Billdog350

After cleaning the under hood grounds, the ground by the battery, and the ground by the drivers side rear tire..the DIC is reading closer to the true voltage now, within a few tenths. The battery still doesn't seem to be holding a charge...it "floats" at 12.5 volts rather than 13.5.

Bill Curlee

Were the ground corroded? What do you mean the battery floats at 12.5? Is that with the key off and no load on the battery? If that is the case, your battery is GOOD. A fully charged new battery is 12.6 volts at rest.

BC

Billdog350

Bill, the grounds didn't seem badly corroded at all. I was hoping for some obvious greenish blue corrosion so I knew I found the problem, but nothing. The ground studs were a little rusted, but everything got sanded, cleaned with contact cleaner, and then dieelectric greased and reassembled.

This red-top supposedly floats (yes, key off, battery disconnected, not charging) at a higher voltage. I was told that it should sit closer to 13-13.5 volts compared to a regular lead acid that sits at 12.6 like you say. But maybe the other source was wrong? I need to buy a battery load tester soon so I can see what the battery drops down to with a draw. It sure seems like the smallest draw drops the voltage on that battery pretty quickly.

I need to check the fuse in my meter, it seems like its not working properly when I hook it up in series.

Bill Curlee

I wouldnt purchase a load tester unless it something that your going to use frequently! Just go to Advance Auto or Autozone and have them load test it. They can do a COMPLETE electrical system exam.

Bill

Billdog350

Harbor freight has one for $20 on sale....not a big loss.

Is it normal for your battery to drop to 12 volts when you turn your key on? it seems like it drops off pretty quickly (from 12.6 to 12) as soon as I open a door or turn on the key...another sign of a bad battery I would guess. The ground cleanup seemed to help though!

Pizzano

Maybe a silly ??, but before tackling the task of cleaning the grounds mentioned,especially the plug in types, does the Battery need to be disconnected, if so Will it reset any changes made to the computer, such as Headlight on/off sensor deactivated, etc.

And thanx for all the useful Info, I bet this Long thread has saved people various amounts of Money and Many Troublshooting hours, and torn out Hair folicles.

thnx

Pizzano

ttt

Bill Curlee

The PCM and BCM grounds do go to some of the grounds that your cleaning. Yes it is recommend that you disconnect the battery prior to cleaning the grounds. I didnt but it didnt hurt anything! It just the right thing to do. Disconnecting the battery is nothing special and all that you will loose is minor settings. One thing that you need to do is reset the code to your radio to something that you can remember. If you disconnect the battery and the radio has the security mode set, it will lock you out!

Pizzano

Thnx, is there a tech article that explains how to program another code in the stereo.

thnx

Bill Curlee

Take a look in TECH TIPS!! I think there is a really good article., If you cant find it, I will dig through my notes and post something.

BC

Pizzano

I emailed the previous owner and they claim there is no code for the stereo, they said they had a dead battery and replaced it and everything still worked normally, can this be true that the stereo does not have a security code assigned to it.

thnx

edlipman

ttt

Bill Curlee

Does it say LOCKED OUT on the display???

ljkuntz

had same fuel guage problem used redline fuel treatment and solved problem now use it every 2 months hope this helps

Bill Curlee

Pizzano

It is possible that the stereo does not have a code assigned to it. It comes with no security code assigned. If no one ever assigned one, you should be all set.

BC