My DIC had been intermittently going blank and not displaying anything. I finally had enough and since I believed it to be within the IPC, I sent it off to "Circuit board medics" to be fixed. I received it back from them with paperwork that everything was working. I plugged it in and the DIC is still blank. Now that this is the case I think it has to be on the car side. Does anyone know which wires specifically provide power and/or ground for the DIC where it hooks to the IPC? Gauges, lights, HUD, buttons, all seem to be working. It is just the DIC is not turning on.

I did not install it completely, just hung it. I thought later that maybe there was a case ground from one of rhe screws, but all the mounting points are plastic, so no case grounds would exist.

Thoughts?

 

 

thanks for sending! Gave me some things to check out!

 

Does the remainder of the IPC work with the key on? Needles sweep, temp, pressure, fuel indicate? If so, then it seems unlikely to be a car problem. Applying +12V to two pins and ground to two pins of the IPC will sweep the needles and run the DIC. I chased my power through fuses, grounds, and DIC buttons only to finally admit it was the IPC itself. Pretty easy to build a connector. The connector, without pins, is available from GM and other sources as GM 12065803 (AKA Packard or Delphi or Aptiv). Pins are also available, but they like to sell them in quantity, so if you want to build your own test unit I can let you have the pins you need.
Connector pin out:
https://corvetteforum.shelor.net/Dia...ml#tab1-653594


IPC Benchtop connector


Good IPC caught mid-sweep on power up.
As you can see from the screenshot, the DIC is immediately on with power. If the remainder of the IPC is functional on bench power, but not the DIC, it seems to me that I recall someone having a dead DIC and fixing it by replacing just the power board in the IPC assembly.
You know, if you want to try a bench test, and will swear on all that is relevant to push rod V-8 to return it, I can mail my test connector and a transformer. Just let me know.

 

The rest of the IPC works, guages sweeping, lights, backlighting, dimming, also the E/M button works as i can see hvac unit ls changing between F and C, so I know buttons are not stuck. I have not physically checked the power and grounds to see if I have both. I am assuming they are there, since everything else is working. That is why I sent it to be repaired. I spoke with them today and a tech is to call my tomorrow. I have heard the data bus may prevent it from coming on if it is dead due to a short on it. I want to confirm with them, this is true or not and then go from there. If only the powers and grounds are needed, I will verify those and then send the unit back as they warranty their work. I appreciate the insight and depending on what I hear from them tomorrow, I may be back in touch. Thanks so much for taking the time to write this up, it's great!

 

Spoke with the tech and he confirmed only 2 powers and 2 grounds are needed to boot up and show needle sweeps and LCD. The blank screen I had heard about is after the initial boot up and you are not seeing "information" in the LCD and it is blank. They gave me a return label, so I can send back for them to look at further. If they return it to me and it still does not work for me but it works on their bench, then I'll want to do my own bench check.