Do you have a picture of EXACTLY where the grounds are on drivers side near the door (1 and 2)? They are hard to find.

 

My DIC lit up like a christmas tree on me today....and neither window would go down. I had the window thing happen to me once just before I stored the car last November, but the next morning all was fine.

Today, went to Radio Shack and all was fine. Put the window up before getting out of the car. When I got back in the car and started her up the windows wouldn't go down. So I drive off. Didn't get out of the parking lot and the Service Traction Control came on...followed by Reduced Engine Power...Check Tire Pressure....Check Tire Pressure Monitors...Low Washer Level (I get that now and then...never use the washers)...Low Fuel (gas gauge went to zero - more than 3 quarters in the tank)...during the ride home the gas gauge went back to normal but all the other things kept coming up.

When I got home I put the tender on the battery. It's been about 3 hours, went out and wiggled the driver's side ground behind the headlight (mine's a nut on a threaded shaft and I don't have the correct deep socket - it's bigger than 3/8 but smaller than 7/16). With the battery tender still connected I put the key in and turned it to accessory and hit the window down button and down the window went. I don't know if it's because the battery tender lifted the battery power or the wiggling of the ground coupler (I popped one side of the coupler back a little with a screw driver but not being able to get the nut off I couldn't remove the coupler completely).

 

Well, today I checked the gang grounds behind the headlights. Both looked pretty good. Driver's side looked great...wire brushed everything (ring terminals & fingers) anyway and used dieleltric grease. Passenger side was just a bit oily on the ring terminals...cleaned everything, wire brushed and dielectric grease.

Started the car up and everything seemed ok...except the windows didn't work...opened the driver's door and tried the window and it worked...closed it and it didn't. Shut the car off and watched the rest of The Masters golf tourny. After the event I started it up and everything worked, windows and everything. Took it for a 7 mile ride. Everything ok. Next weekend I'm gonna check out the window wire couplers.

 

vettedawg-

the connector for the wireharness that goes thru the door needs attention. I'll look for my post to fix this

Here it is:

I've been lurking for weeks trying to self diagnosis my problem. What happened about three weeks ago all the warnings came on and it said check tire pressure, low power mode, check active handling. Had no power windows, what a mess. So being the do it yourselfer I am, I disconnected the battery and it temporally fixed it for the last 1,000 or so miles. And now it.
's back, can't clear it what ever I do it keeps coming back. Also lots of trouble codes, I mean LOTS! Like 24.
I notice that when it was sort of working ok the memory seat doesn't always work every time, also when I drove it at dark in the morning about 1/2 mile from home the lights would dim slightly for a brief moment then be ok. If I need a PCM where's a good place to get it from. I did clean and check the grounds under the hood, 4 of them and they were super clean to begin with. The car has 30,000 miles and is in terrific condition. when I relearn the PCM clear the codes it runs great, then it starts usually with the buttons not functioning on the drivers door, then the active handling light coming on then after a few sec's everything goes REAL WACKY. I need help TIA Dan from MI

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Hi All- on the way to work this morn it did it again. After clearing all codes the dr door switches were still inoperable. So I opened the door and grabbed the wires in the dr opening and moved them back and forth while pushing the buttons and then the switches started working. I think the dr door harness is where the problem is? I talked to a service eng. at GM this morn and he said that’s the place to start if it was a BCM it wouldn't be intermittent like I'm having. He said harnesses that pass thru doors is a big problem.

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His fix for me:
Power door lock or power window may be inoperative or intermittently may not work from one of the doors.



Recommendation/Instructions:

While attempting to operate the function, grab the conduit of the C201
connector and move it back and forth. If the function now operates, check
corresponding connectors to ensure that all of the connector pins are fully
seated and are free of any corrosion.

Care should be taken to check for a deformed (too large internal diameter)
female pin. Replace loose/damaged female terminals in connector. Usually
terminals A, B, C (power and/or ground) C200 and C201 are located in
corresponding "A" pillar just inboard of door hinge area harness
conduit/pass-through.
-It's fixed, good as new

 

Thanks muchly!
...just trying to envision the "A" pillar. When I think "A" pillar I think up at the rear of the windshield.

 

All I cleaned the grounds and still had the same issue. So I was starting to look and all of my wires that are near the exhaust and found that the main harness going to the starter and to sending units on the block and the oil pan were melted together. So I pulled the passenger header off and the starter and pulled apart the individual wires and most of them were showing (COPPER).

I guess my 1st question is, Is there any heat resistant material I can use to place my wires in.
2nd question is should I replace the melted wire with a heavier gauge wire.

Thanks

 

I assume you have aftermarket headers? I was under my car last winter and noticed that I was starting to see some melting on the main wire harness insulation as well. I went down to the auto store and bought some muffler tape as a quick fix. I think after seeing this that I am going to order some header wrap and cover those wires before I have the same problem...

 

Yes i do have aftermarket headers(kooks) brothers with a 3" collector. I zipped tied all of the wires away from the header as best as I could. there is a lot of heat so I would recommend a header rap. Or just the collector.
Thanks

 

[QUOTE=TheeMike;1564491331]I am amazed at the response time!QUOTE]

...me too.

 

All, I have read Bill Curlee thread up and down. I went to my 02 Z06 and cleaned all of the grounds. I cleaned them and most of them were in pretty good shape. The car is rarely driven in the rain or snow. I live in St.Louis MO. I did find some frayed/melted wire going down to the starter. I replaced the wires and shielded them. Went to start the car after all of the repairs and got the dreaded service traction control, low voltage, reduced engine power,and service ABS. I turned car off and then it started just fine. I know this sound like the grounding issue. The check engine light come on is the one for the throttle body getting low voltage. I clear the code and the car starts and runs fine. I drive the car somewhere park it and then when I return it does the dreaded lights flickering on and off for a few seconds then starts. I can't figure it out. Any help would be great because I hate to see my Z just sitting in my garage with the car cover on it.
Thanks ALL.........

 

In the electric world, they make this cool stuff called heat schrink only draw back is the larger diameter the more expensive it is. look like the connectors are about 2 inches, you can buy a long strip before you take them apart, do all of your cleaning then slip it over the connector, put it back together, apply a little heat, it will schrink up nice and tight and should prevent further corrosion, especially if you use somekind of anti corrosion as well. just some food for thought.

 

I too have the infamous "Reduce Engine Power" etc electrical faults in my '99 Coupe, auto trans, 41,000 miles. Just a brief description of events. While driving along at 30 MPH (school zone), I lost power to both doors, radio, gages went wild, and DIC flashed about every warning known to man. Having just read Bill Curlees post about poor or compromised chassis grounds, I'd like to check out grounds G201 (left side 'A' pillar) and G202 (right side 'A' pillar) as they are related to the door modules. Does anyone have experience accessing these two ground points? Does it require fussy removal of body panels or interior shrouds? Or am I heading down the wrong path? All comments are appreciated.

 

Yep! Wrong path! Go STRAIGHT to the wiring harnesses in the door accordion tube! If the doors lost comms, that the MOST LIKELY cause of your problems! Go there first and PLEASE let me know what you find and how you had to repair the problem. Look foe damaged wires and seperate EACH connector and examine each female pin.

BC

 

would that make dic work only when it want to?

 

That just sounds BAD... (and way too easy)

 

Bill - I have a 2002 Z06 and may have this problem. 3-4 minutes after start, bells, warning lites, all gages go to full deflection or zero, display cycles thru all warnings. I stop the car, turn it off, wait a minute and restart. Usually goes away but it is happening more frequently. Does that sound like ground problems or a module??? Thanks. Les - Dice13

 

Normally when mulitple modules are effected,,the fault is the serial data buss. A ground or short to another signal wire can and will cause it to FREAK OUT. The only reason I suggest the door harness is that LOTs of people have this very issue and that causes the problem. There have also had simular problems with the drivers seat control module connector (has the same serial data wire in there too )

Another place that will cause TONs of lights, bells, whistles and codes is the Body Control Module (BCM).
If it gets wet / damp/ or gets corossion on the back of the circuit board (yes they do corrode if you have a wet passengers foot well) the car will freak out.

So,, your mission is to figure where the serial data wire is having issues.

I start at the door accordion tube. Its easy and quick!

BC

 

About the fuel sender, I was advised of the solution to this issue. I solved thesame issue on my C5.The problem starts when i fill up and my fuel goes below 3/4 tank then my guage suddenyt drops to empty. I had to set my trip meter before each fill-up just to make sure that I did not ran out of gas.I started adding Chevron with techron gas additives. I did this for bout 4 times in two months using the 20oz. bottle and emptying it before filling up the tank. I also use Chevron with techron gas station as much as possible, ( I'm not advertising, I promise!), In the first month I tried it I noticed a dramatic effect and at the end of the second month the problem totally dissapeared. I was releived. I hope this works for you and for everyone!

 

So do you guys agree that the P1571, C1277 is a problem on 97s that can not be fixed?

 

does anyone have dic for sale i cant even clear change oil message