Help! gauges and DIC center only coming on about half the time and getting worse

[biggy-1]

I thought it was most likely a ground problem. I checked all the ground locations I could find and they seamed to be clean and tight. Anyone have any other ideas what may be causing it?

 

[dadaroo]

Please explain what "not coming on" means. No lights or gauges are not working or both? DIC message display not showing anything? Do the IPC indicator lights ( CEL, Brakes, ABS, etc.) "illuminate" temporarily to indicate the bulbs are working?

 

[biggy-1]

all the lights in the dash work but the gauges, speedo, tach, heads up display and dic do not work.

 

[dadaroo]

Check fuses 19 and 25 in the I/P fuse box. If they are good then either G104 ground is bad or the IPC motherboard is the issue in my opinion. I'm betting on the motherboard. Let us know what you find.


Mr. Sam

 

[biggy-1]

fuses are fine, ground seams ok also. so your saying my car needs new ipc motherboard or do I need to get scan tool and check all components.

 

[dadaroo]

I think it is the IPC. It is just as easy to get an IPC as it is the board. That board has the mileage on it so you may have to have it changed after you swap.

Marc at VetteNuts.net can help you with the IPC.

Even using a Tech 2 is not going to help you with this.


Mr. Sam

 

[biggy-1]

how hard of a job is it to change ipc and how much is the cost?

 

[Junkman2008]

... Even using a Tech 2 is not going to help you with this.


Mr. Sam

Actually, a Tech II can be used to do a gauge sweep, which will help verify that the IPC is actually bad. OP, do all the gauges sweep when you turn the key?

 

[dadaroo]

I agree Junk, but his Post indicated nada. OP please clarify.

His DIC is not working either and in every case I have worked it is the IPC motherboard.

Here is how to access the IPC. A replacement would be abut $200 or so.

Installation of Vette Essentials' Custom Emergency Brake Handle and Boot

PS: Don't be fooled by the link title. Removal is easier than it looks like from the link.

 

[50anni]

I thought it was most likely a ground problem. I checked all the ground locations I could find and they seamed to be clean and tight. Anyone have any other ideas what may be causing it?

I had a similar situation happen to me in my 2003 50 anni. Started it up and had no dash info or DIC info. The only thing that worked was the Tach if I remember correctly. I was in Effingham, IL at an Action Event and asked Mid America for help. Paul Koerner happened to be there and asked a lot of questions to try to determine what it might be. Ended up it was one pin on a six pin plug under the dash driver side. He replaced the one pin and its worked fine ever since. That's at least 5 years ago.

 

[biggy-1]

most of the time when I turned the key on the IPC, DIC and HUD would come on and stay on or not come on at all and stay off. 2 or 3 times I recall it either went off when I hit a bump or would come on when I hit a bump that's why I thought it must be a ground problem. it has been a week now and has not came back on at all. also not working is the power windows and radio when the car is running. but they both work when the key is on acc. only.

 

[Junkman2008]

That's the kind of information that you should have provided in your INITIAL post! That tells me that everything works, there's just a connection issue. Now all you have to do is start the car up and start banging around the areas that affect the IPC. The first place I would start bumping around/moving cables is the area in the passenger's side floor board where the BCM is located. I would be checking that area for water damage. You don't have a bad part issue, you have a connectivity issue. Do you have the service manual for your car?

 

[biggy-1]

yes, I have Mitchel online manual. I will try moving things around if that does not work I will start pulling connectors apart looking for rust and spraying them with electronic cleaner.

 

[50anni]

most of the time when I turned the key on the IPC, DIC and HUD would come on and stay on or not come on at all and stay off. 2 or 3 times I recall it either went off when I hit a bump or would come on when I hit a bump that's why I thought it must be a ground problem. it has been a week now and has not came back on at all. also not working is the power windows and radio when the car is running. but they both work when the key is on acc. only.

It sounds really similar to my details. I was fortunate enough to get it fixed the day it happened. Have you checked to see if any fault codes are set?
Again on my situation sounds like yours. The symptoms are almost identical. I didn't live with the problem for long, so I can't tell you any more symptoms noticed while driving. I do remember my radio, power windows, AC controls, did not work. It may be worth your time to look under the dash for the six pin connector that goes to your driver side door control module. It is in the middle of the area under the dash in front of the driver's seat. There is also an identical 6 pin plug under the dash in front of the passenger seat that connects the passenger door control module. When Paul Koerner pulled the six pin connector apart, he was looking for good connections on each pin. That's when he found one pin not making good contact as it was a little discolored like it had been hot. You can contact Paul on this web site "Attention Paul Koerner" or at his website The Corvette Mechanic.com. Google Paul Koerner Corvette Mechanic if all else fails. He is simply the best at this! Factory trained World Class corvette tech.

 

[Junkman2008]

His situation doesn't sound like yours at all. The only thing not working on his car is the IPC. The issue you were having is somewhat common and happens from time to time on a few cars. There are a few threads about it on a few different forums.

Paul is the best at what he does and I don't think that there is anyone better. He also post here on occasions. When I use to do the Corvette circuits, I had a chance to hang out with him and bounce questions galore. The guy is like E.F Hutton to Corvettes. He puts on great seminars.

 

[dadaroo]

At some point you may have to access the IPC and look at the connector and pins there. I did work on one case where there was a power feed and a ground pin that were not fully seated into the connector. Once that was done it fixed the intermittent IPC issues. This was after the dealer replaced the IPC under warranty and it did not fix it. He was having more issues than just the gauges, everything was going wacky.

However, the fact that only the gauges are affected and nothing else it sounds like the logic board is suspect.

 

[biggy-1]

It is not just the gauges. The DIC and HUD are also not working. Plus the radio and power windows do not work when the car is running but both do work when the key is in acc. position.

 

[Junkman2008]

Have you checked the area that I mentioned yet?

 

[biggy-1]

yes I moved things around down there pulled a few connectors apart still nothing working.

 

[Junkman2008]

Did it look like any water had gotten in there? Was anything damp?