Bill Curlee

A SOLDERED connection is always the best! Then the crimped connection with the appropriate anti corrosion compound and last but not least the crush connection. If you look under the plastic cable connection sovers you will see that GM used a crimp connection and it sometimes fails.

silvertonbass

Hi Guys,

My 99 vette was running fine, i shut it off, came back to it in about an hour, the power came on as i was going to start it, it make a few clicking sounds, and then there is no power at all. Could this be a fuse that was blown or a ground somewhere? If anyone could help, i would appreciate it greatly.

thanks

bob

02Z06EB

thanks bill, i figured soldered was the best but when i saw the compression type i was curious because of the ease of use.

for what ever reason my electrical issue is gone, i did tightend down on the side post terminals but im leary of them and will get the top mount solder type done this weekend.

thanks for the informative and great thread, this community is what makes owning a vette even better, that we can avoid high cost at repair shops.

02Z06EB

ok this is getting frustrating.

i thought i had something drawing a load while the vehicle was off. then tested it per your instructions and it appeared that i only had a .01 draw in sleep mode.

but i was till going to change my terminals out to top mount, i suspected they may vibrate loose, i just dont trust them after having to change the bolts out and feeling like i may have slightly stripped them.

but for the past 3 days ive let it sit, and been checking the battery voltage once or twice a day. it was holding at or above 12V each time. i even started it once and the dash volt reading would get up to 14.1.

so i thought all is well, no current drawing gremlims. so today i get in it to take a drive and before i do i read the battery voltage across the battery and its above 12V. im happy.

i get in an crank it over and all i get is clicks. i re-read the voltage across the battery terminals and its barely above 9V

how in the hell did it drop it down like that?

i dont understand, im getting .01 when hooking up my meter in series to test for current draw while in sleep mode.

ive always been able to let my car sit days or even weeks without ever having a problem of starting it right up.

could a loose terminal do this. is it possible the loose terminal is micro arching and shifting the electronics into non-sleep mode and back to sleep mode throughout the sitting period?

or could it be my battery? its only a month old and its a redtop optima. when i first bought it, it wasnt charged which i thought was strange. maybe it was old and wont hold a good charge?

problems like these almost drive me to just saying to hell with it and trading it in for a newer C6Z(which i love my FRC but cant stand problems like this)

Bill Curlee

For a battery to go from 12 VDC to 9 VDC would require one or both of theses things to happen:

- The battery is bad. (have it checked out at autozone)
- The battery connections are still bad and there is some sort of resistance at the terminals (not likely)

Have the battery tested and that will prove that theory out. Your BCM goes into sleep mode after a time period of no additional current draw. If it detect current draw, it comes out of sleep mode and monitors the rest of the modules for information.

After the period of inactivity required for sleep mode, it goes back to sleep.

If you have a bad connection at the starter or a bad solenoid, it will cause it to NOT energize the starter.

If you have a bad start enable circuit, it will also cause the engine /starter to not crank.

BC

02Z06EB

yep took the battery out and had o'riely's check it out, it was bad.

when i first installed the battery it was dead but i went ahead and jumped it. now looking back it makes sense. i was driving it daily so it seemed to hold up. but the first time i let it sit for 3 days it was dead.

and just for everyone's info who doesnt know this, the guy told me not to charge these optima redtops with a standard charger, it will cook them, because thats what happened to me. i noticed after i put it on the charger it was burning hot. but i believe the battery was bad before that, i only bought the charger because it would go dead.

he said you need a amg charger.

anyways, im gonna install the new battery in the morning and see.

wcsinx

I had a few electrical gremlins, and I just found this thread this morning. Let me start by saying WOW what a wealth of information, and thank you Bill for your contributions.

Bill, in your opinion are the grounds that terminate to those plastic junction plugs much more subject to failure than the plain old bundle of wires crimped together type? I have 0 problem with hacking off those plugs and soldering everything together. I ask because all the lugs I see look fine ... no corrosion, but I haven't yanked anything apart yet, and I've seen those pics you posted of yours.

I'm thinking cleaning those grounds might clear up a few of my minor electrical gremlins. I'm getting the following codes...

B0432 Rear Defogger Relay Circuit
B0332 Outside Air Temp Sensor Short to Ground
B0337 Inside Air Temp Sensor Short to GND
B0361 Left Actuator Feedback Short to GND
B0365 Right Actuator Feedback Short to GND
B2265 Vertical Position Sensor Circuit

Those all show History btw. Any idea which ground lug those point to?

I'm also getting an intermittent Service ABS/TC/AH message, but I'm 99% sure that I can clear that up by cleaning/fixing/replacing the wheel sensor harness as is indicated by the C1232 code I'm getting.

Thanks again!

Rick Perkins

I removed and did the ignition switch service today. I found nothing really wrong with the switch. I also took the climate control out while I was there and did the soldering on the problem points. It actually works now. I changed the rear rotors and pads today also but that's another story.
I found a broken wire on the A/C compressor and sodered it together and coated it with liquid tape. I put everything back together, started the car and got and almost immediate Reduced Power alarm along with the same multiple alarms I've been getting. The car actually seems to be coding more often than it did before. I pulled multiple history codes after I shut the car off and reset everything. The one that really bothers me is the A6SCM No Communication. I looked up what codes were common and it seems most all of them are communication errors from the computers. The most common ones are U1064, 1096,1016, 1096,1255. These are in every catagory. There are a few other oddball codes but they all go to commuication losses. I'm at a loss where to go next.
New as of 1/26/09. Drove the car to work today. "NO CODES" except for the security light came on. Then I hit a bump in the road on the way home and it began coding.
My question is: Could the VATS be part of the problem? I can turn the ignition switch off and on two or three times and everything seems to clear up. Like I said: I bought the car knowing it had a few issues. I'm just trying to be patient and fix everything right. By the way. I did find a bunch of wires to no where behind the climate control. Possible previous stereo. Makes me wonder if installer mess up some wires.

Thanks for any assistance.
Rick Perkins

paulmcp

I am new at this but i hope this gets on to the threads.
As usual Bill Curlee is a huge help, again Bill thanks for all your help.
I have been reading the threads, and see so many problems with codes popping. Before i put the car to sleep for the winter as Bill knows, i had more lights than a christmas tree, some of the codes were:
Traction control, tork signal malfunction, rear defoger circut,several no coms and on and on.
Well I bought the car from a reputalbe BMW dealer, and they did take care of me. The key for all the codes for me was: "Repaired connectin at the fuse box, and repositioned fuse in box" That is what they say they did and i drove the car several more times before i put it up for the winter, and had no codes at all. A mechanic friend of mine told me that any drop in voltage in the intire system will set off codes.
I hope this helps for you folks that are having codes. This spring i am going to cleann all the grounding connections i can, as Bill sugested.
My Vette is a 2001 Thanks Paul

wcsinx

I pulled those 2 front plug-type ground terminals this weekend, and there was quite a bit of corrosion on the driver's side but not much on the passenger side. I sanded them down, then sprayed them with contact cleaner, globbed some silicone grease on everything then plugged them back in.

Annnd voila! The HVAC codes aren't coming back up. They used to pop back up within seconds of clearing them. Funny considering I never had the first problem with the HVAC.

Also pulled both front wheel harnesses and did the same thing there. Curiously enough, the harness for the wheel that the code came up for had fallen off that black plastic clip that holds the inboard end still. So I put that back together and also made a ziptie loop around the lower a-arm so that the wires wouldn't dangle beneath it anymore. (Can't believe that's how it was designed ) No more codes from that wheel now .. fingers crossed

Next on the list ... pull the door harness out and take a look. Those pictures 2 pages back scare me.

Rick Perkins

The door harness is actually pretty easy. It's harder getting the accordian tube out of the way for the plug disconnect than anything. When you put it back, push the connectors back under the dash side. Put a little dish washing soap on your finger and spread it around the leading edge of the tube. It will pop right back in the hole without a lot of cursing.
Rick

Bill Curlee

Back in 2005 I spoke to a GM Engineer about the POOR GROUND CONNECTOR design and if they had any plans on making them better on the C6 Vettes. He said " I recommend that you hack off those connectors and terminate them in an eyelet terminal and make sure that you solder and crimp them in.

Well low and behold, the C6 Corvettes have the ground wires in a crimp/soldered eyelet terminal. So, if you want to , YES, it will make life easier.

Rick Perkins

I've got to tell someone about this. I did the service on the ignition switch contacts and then had the key cylinder changed out. ( the key would vibrate out of the ignition)
I kept getting a A6 SCM No Communication along with multiple other codes and a reduced engine power alarm. So I looked under the driver seat and low and behold 6 wires had been cut. One to the telescopic wheel was cut and 5 of the 6 to the scm. I repaired all of the wires and so far no more codes. I truly cannot understand why someone would cut those wires. I was not aware that so many different circuits in these cars had such an effect on so many other systems. Just goes to show that you have to fix em all.
Rick

blktie8

Hey Bill
I noticed the 2000 corvette HVAC is not working right
Blower works sounds normal
but no real heat or cool is coming into the car
Any ideas
John

Bill Curlee

John

I need a LOT more info that what you provided to fix this issue.

MANUAL or Duel Climate Control?
Any DTCs for the HVAC System?
Can you control the HVAC vent locations and does the air come out only where you direct it to?

Thanks

BC

cruisemon

Bill - the ground location schematic looks like it is in a Helm Service Manual. I have looked at every page in Section 8 in my manual and cannot find those schematics. Where are they? Section and page number would be great.

Charlie

Bill Curlee

Charlie

Yes there from the factory service manual. Its out of a 98 manual. Some of the newer manuals are different and may not have that exact drawing. The newe manuals have one that looks like this:



Im in Guam so I dont have access to my manuals.

Bill

ruffian

Hey Bill, or anyone, Hoping for some ideas ...

Wife was driving on the freeway, calls me laughing says, "haha funny trick changing the speedo to kilometers" I hadn't changed it... she then pokes the Reset button, vs the km/m button on the cluster and bam! Instrument cluster goes dim, odo blank, she immediately is decelerating and cluster comes back with "reduced engine power". She pulls to the shoulder asap and checks her shorts... lol Tells me that she couldnt' maintain speed at all and was about to get run over by a semi! Great! Just what I want to hear... I asked her to turn engine off and restart the car presuming the PCM needed a reboot. "Fixed" she says... no further problems that day. Very scary situation.

I checked the codes when she got home and I pulled quite a few:

PCM - P1416 H C - (I know this guy, I need to clean the AIR valve.. unrelated imho)
BCM - B2482 H Backup light relay
U1016 H Loss of comm to PCM.
SDM - U1016 H
U1040 H TCS loss of comm to PCM.
IPC - U1040 H
U1016 H
Radio- U1016 H
LDCM- U1016 H
RDCM- U1016 H
SCM - U1016 H
B2606 H Rear seat vertical sensor
RFA - U1016 H

Ok, so my take on this looking at the common denominator, Loss of Comm between several modules and the PCM... Bad connector connection, or maybe power/ground in common? I've checked the under hood grounds, I've got tight connections at Battery, and any connector I can put my hand on without removing an access panel. No smoking guns.

Next day.... She is driving along and at two stop lights in a row, the rolls to stop, clutch in, and the odo fades to nothing and reduced engine power comes on momentarily along with check engine light and both go away. No other issues.

I pulled codes and I get PCM 1416C H - yeah yeah I know already... ;-)
and SCM B2606 H. These both showed up previously and I can't see a reason why 1416 would create a problem, so I am ruling it out. However... the SCM seat back code, that's weird. She's 5'5" tall and runs the seat far forward compared to me, I run the seat all the way back. She was on the brakes for both of these last incidents, but the first major she was on the gas. No brake relay this time either...

I'm over thinking this I'm sure... But I have Never (knocking on wood) had a problem where the car behaved badly except when I almost allowed a rubber intake spacer to get ingested into the intake manifold...

Can you think of a reason why the seat back vertical sensor would cause a problem with PCM comm?

I need a nice dry day when I can go crawl around next to and under the car so I can really dig for problems. But I would really like some ideas. My wife is losing confidence in the car and doesn't want to get stranded, for that matter I don't want her to get stranded.

It's her car, if mama isn't happy, I'm not happy... Thanks in advance! Bob

Bill Curlee

Your and my wife would get along well. She has her own Vette/s also (71 and 06 Z51) I get the same phone calls. (cars doing weird stuff, come get it!) I love my wife so I always respond rapidly and resolve the issues.

First thing that I would check would be the seat control module wiring harness for damage. Those under seat wiring harnesses and connectors can take a beating.

Next is the passengers and drivers door wiring harnesses. Pop out the accordion tube and fish out the door wiring harnesses from the door frame opening. Look for bare wires.





Seal that bare wire with liqiud electrical tape.

Report back the reults

BC

ruffian

Thanks Bill,

I'll check out those areas you suggested. When you mention the seat harness, it rang a bell. The previous owner said he had the dealership he bought the car from replace the driver seat shortly after he bought the car. He said it was rocking badly.

I'll report back, it's supposed to be raining next few days so may not be until the weekend.

In the meantime I need to teach my wife how to pull codes. ;-)

bob