Has your digital cluster failed or is giving you issues? This may help....

[Starflare5]

Hey all,

 

I have done alot of research on this site and others about the possible digital cluster failures (both base and UB3) on older W-body vehicles, and, have even had the failures happen to myself as well. I found the best and least expensive way to take care of these issues is to repair them on your own. Now depending on your cluster and type of failure, you can determine what materials you may need to repair or service it. Here are some notes to consider:

 

- Both Cutlass Supreme Base and UB3 full clusters used flourescent displays.

- Grand Prix Clusters used a combination of backlit LCD (commonly speedometer only) and analogue guages. Regal UB3 clusters also used all backlit LCD.

- Regal base clusters were replacable component based and used a flourescent display for the speedometer only.

- The materials you may need to diagnose, service, and/or repair are a flashlight (for backlit LCD type), rubbing alcohol (70% recommended. Any higher can leave a film, any lower is more water) and q-tips, and/or possibly a 30 watt at max soldering iron. Any higher soldering iron may cause damage to the object you are repairing.

- The most likely failure with flourecent display type clusters or components is cold solder joints.

- The most likely failure with backlit LCD display type clusters is burnt out or failing bulbs, and/or dirty contacts.

 

What to do if you suspect a failure:

 

First of all, if you're not comfortable with taking apart or repairing electronics, including using a soldering iron, I suggest that you get someone to help or take the cluster to a repair shop, even though, a repair shop will usually be the most expensive route.

 

Secondly, if you have a base cluster, and have the money to upgrade to a UB3 cluster, you should do so due to it being a less expensive route than the repair shop. Just keep in mind that you may also need to replace the harness, oil sending unit and temp sending units in your vehicle.

 

Now, let's look at the failures a little more closely:

 

If the speedometer on a Grand Prix Cluster has appeared to fail, or, parts of or all of the Regal UB3 cluster has appeared to fail, shine a flashlight into the display where it appears to have a failure with the vehicle running. If you can still see the display showing an indication that it is working, most likely issue is a light bulb or several of them. Your first steps to repairing this issue should be relatively simple. Remove the cluster and replace the bulbs. You may also want to clean the bulb contacts with rubbing alcohol and a q-tip for good measure.

 

Go ahead and test the the cluster once again after this. Hit, tap, or shake the cluster, not hard, but hard enough to jar it, in multiple places on the mainboard. If the cluster still appears to not be working or flickers, it is most recommend that the solder joints on the mainboard all be re-soldered.

 

If there appears to be no display at all, or, the display appears to be backlit, but, has no indication that it is working properly, then the failure may very likely be in the display contacts themselves as well. This is where it may get a little complicated. If this type of failure has occured, you are most likely going to have to actually take apart the cluster or take it to a repair shop. If you take apart the cluster, have a pair of pliers available just in case. In some cases the LCD displays were held into place by a metal housing that was either held to the board with metal tabs, or, by screws. Remove this metal housing and display. It will most likely have a contact transfer band just like a digital watch and a plastic inner housing behind it. Clean the display at where it makes contact, the contact band, and the board contacts (if reachable) all with rubbing alcohol and q-tips. In some cases the LCD might be attached with pins soldered to the board. Re-solder each and every pin. You should also re-solder the IC controller on the board in this case anyway. This is often an odd and silent culprit that can reappear at any given time without warning if not re-soldered properly.

 

On the Grand Prix cluster, if multiple guages have appeared to have failed as well, go ahead and re-solder every solder joint on the mainboard. Also do this if it appears that every light or bulb has gone out all at once or is flickering in the cluster with either Grand Prix or Regal UB3 clusters.

 

With Regal and Cutlass Supreme base clusters, the failures that commonly occur is speedometer goes blank, odometer stops working, fuel guage stops working, or, all three have appeared to have stopped working altogether. Depending on the type of failure, the repair can be simple and quick, or a little complicated and time consuming.

 

If all three have appeared to have stopped working altogether, go ahead and re-solder every solder joint on the mainboard first, then test the cluster. If it fully comes back to life, hit, tap or shake the cluster not hard, but, hard enough to jar it, in multiple places including the back of the mainboard and displays. Take precaution and be very, very careful not to damage the display glass. If any component of the dash appears to flicker, you may need to re-solder the IC(s) behind that component as well. With Regal clusters, the ICs will most likely be flatbacked, or, soldered directly to a board. With Cutlass Supreme clusters, the ICs will mostly be the pin-through type, or, be attached via their pins sticking through a board and soldered. Take extra precaution when soldering flatbacked ICs for there pins can be very easily moved or broken once the solder holding them is softened. Take note that even if the solder is holding a pin in place, it may not be making actual contact with the board.

 

If just the speedometer display has gone out, but, all other components of the cluster are working, you must not only re-solder every solder joint that attaches the display to the board itself, but, also every IC solder joint as well. This will prevent future failure.

 

With a Regal speedometer display, for good measure, clean the contacts on both the back of the display board and the contacts on the display to mainboard bridge as well with rubbing alcohol and q-tips for good measure.

 

If the odometer has stopped working, first, re-solder all solder joints in the mainboard behind it, then test. If it still appears to not be working, replace the odometer component.

 

With Cutlass Supreme UB3 clusters, there are 2 multi-function flourescent displays. If there appears to be a failure even with just one guage or indicator in either display, it is recommended that you resolder every joint and component attacted to that display.

 

For those of you upgradng to UB3 clusters, here's some basic wiring information:

 

Here is a simple description of the common dash panel wires and their function on your GM

Vehicle. There is also here notes on upgrading your vehicle's dash panel. Please take

note that if you do upgrade, it is recommended that you splice in the wire harness of the

new or full dash panel instead of replacing the old harness completely.

 

Special Note and Service Bullitin: If you own an Oldsmobile Cutlass Supreme from 1988 to

1993 equipped with a standard 3 point/guage (Fuel, Speedometer, and Odometer only)

florescent digital display dash panel, it is recommended that you upgrade to the full all

guage (Digital Florescent or Analog) or get it completely re-soldered and serviced due to

several issues with the 3 guage panels including the main controller chip also known as a "

Smart Driver" having solder joints fail over time.

 

 

Pink w/ Blk (C1-Fuse#11) = IGN

Orange(D16) = Memory/Battery Constant

Grey(C11) & Yellow(C10) & Brn w/ Wht(D10) = Dimmer/Light Switch

All Black & Black w/ White = Ground

LT Blu = lft signal

DK Blu = right signal

Tan w/ wht = Brake Warning

Grey w/ wht = NC(No Connection)

Tan w/ Blk (C6)= ECM/Shift

Lt. Green = Headlights/High beam indicator

Orange (C13) = ECM/Data IO/Tachometer (Note: If you had a basic dash

without a tach, this wire can be linked to the orange wire on the

diagnostic connector under the dash to enable the tachometer on a

dash cluster with one. Also, if you originally had a basic dash

without a tach before, you may not have this orange wire in the

wire harness the car came with.) With Buick Regal, this may appear to

be a white wire as well.

 

Pink w/ Blk (C16-Fuse#9) = IGN

Yellow(D2) = Chime Module

Yellow w/ Blk(D3) = ECM/Low Coolant Warning

Brown(D4) = Alternator/Generator/Voltmeter

Brown w/ White(D5) = ECM/Service Engine Soon/Check Engine

Tan(D11) = Oil (Note: If you originally had a basic dash, but now

have a dash with an oil guage, the oil pressure sending unit will

have to be changed as well. If you do not change this, the oil

pressure will come up as high all the time.)

 

Dk Green w/ White(D12) = Temp (Note: If you originally had a basic

dash, but now have one with a temperature guage, the temp sensor

will have to be changed as well. If you do not change this, you will not

have any showing of temperature.)

 

Purple(D13) = Fuel

Dark Green(D15) = ECM/Speedometer

 

Well, I hope this helps answer and consolidate alot of questions for you guys.

 

Thank you,

 

Starflare5.

Edited April 3, 2012 by Starflare5
Spell Check

[94 olds vert]

So much great info in that post. A post has never been more worthy of a thanks than that one.

 

I installed a digi cluster into my 1994 CS and if anything happens to go wrong I will feel a lot more confident about repairing it myself.

[RobertISaar]

good post.

 

just a suggestion though: i use a 45 watt iron for everything i do.... i have not yet killed anything because of heat.

[alec_b]

I swapped in a UB3 digi in my '91 Regal because of a random low fuel, low coolant, and check gauges with the full analog package. All I had to do was tap into serial data. Loved it!