thmupr

So I’ve been working on fixing some issues.. hud, light bulbs to LED, rattles... anyway I found a new buzzing noise coming from the instrument cluster.. only buzzed when the park lights are on, and is affected by the dimmer.. Any ideas what fixes that buzzing?
Also.. anyone know the part number for the foam strip between the front edge of the dash and windshield?
Is this considered the lower windshield seal? I assumed it was anti squeak or anti rattle...
Thanks!!

Bill Curlee

The only thing inside the Instrument cluster that I know that will make any buzzing noise that is related with the dimmer is the 12 VDC to 700 VDC florescent light voltage inverter.
The actual cluster gage faces are lighted by TWO 4" BLACK LIGHT Florescent tubes at the outer ends of the cluster The gage faces are painted with DAYGLO type of paint and glow brightly in black light.

That inverter can make noises if its going bad or aged. If the black lights still work, I would remove it and make sure there are not any components that are ready to smoke.
You CAN NOT purchase that inverter separately. You would have to find a used part, whole cluster for parts or cobble in an aftermarket inverter.

You can unplug the inverter and see if the noise stops.

Bill

Bill Curlee

Here are some IPC post that detail taking the cluster apart. The inverter is silver box on the back of the IPC. Hope all the pictures are still available.

- C5 Gage Cluster disassembly - http://forums.corvetteforum.com/c5-t...post1570380674



- C5 Gage Cluster Post - http://forums.corvetteforum.com/c5-t...post1570380878

Bill Curlee

NOTE.. The cluster chime is produced by a SPEAKER inside the cluster. The speaker has an amplifier driver circuit and a oscillator to make it chime and operate. If that driver or oscillator dies, it can make a very weird noise. It really should not be effected by the dimmer or lighting changes.

The noise usually sounds like a nasty screech!

thmupr

Thanks Bill!
The cluster is definitely the source of the buzz... I unplugged it and the noise goes away. I opened up the inverter and there is a small piece broke off a choke coil on the circuit board. I figure it’s on it’s last leg lol!

ncali

Bill ,
I have just read the links that you posted and learned that the main board contains the odometer and the DIC

I have an old cluster with the correct mileage for my car. I changed it out because the DIC buttons on the right side of the dash no longer worked. The Dic did show messages on the display. I found that my DIC buttons had no response when a tech 2 was connected.
With the DIC displaying messages ( tire pressure, Low oil Etc...} would you think the main board is bad ? would you know which
ic is controlled by the dic buttons, stores codes

also , how can I change the mileage using my tech 2

Bill Curlee

The TECH 2 CAN NOT change the mileage on any Corvette. It takes a proprietary interface to change the data in the IPC. With that being said,, There is a small IC on the mother board that contains the data. You can swap that IC from cluster to cluster If you damage it during the swap, the data is GONE

Does your buttons on the right side of the IPC function now?

If so, read the DTCs that are present and post those.

Bill

ncali

I am working on a 2000. I pulled the old IPC apart this evening and can now see that the mother board contains everything. On the back side of the mother board I have several spots that look like the solder got hot a popped . I can also see that I would make a mess out of that board if I tried to change any of the components. I suppose my best bet on correcting my mileage will be to go to the speedometer shop and have them do it .
I have an extra dash if it can help anyone

Thanks Bill

GCG

Did you take pictures of the broken component?

thevelvetglove

Yes that is what it sounds like. Thanks