I am boggled by this one. The cluster seems to have a defect that is bought on by cold temps and is cured when the dash warms up with the heat on (I am assumming). If you are so inclined to remove part of the dash to replace it, than you should unplug the wiring harness from the cluster and put a voltmeter to it and see if the cluster has constant power coming in to it just to be sure.

I have a 2002 Sable that I got about 2 months ago and I'm having a very similiar problem. My dash lights are in op as well, but they never come on even after the car warms up. Everything else is functional, but not the dash lights. I'm thinking that its a loose wire since the radio works intermittenly. Hope one of us can figure this out soon!!!:confused:

sable dash light issues
 

I have 2001 merc sable with the exact same problem for the last 5 years except mine has not worked at all for over a year. At first they would not work for days and then come back on for a few days regardless of the temperature outside. Any luck correcting the problem yet?

i am having the same problem been going on for about 2 years now when it started i was able to slap the top of the dash and the lights would come on but now nothing the blinker lights stay on. druning the day one blinker light will shut off but at night both are on. so i have read all the post on this page has anyone ever fixed the problem yet i think i might take a part the dash and clean the plugs on the back of the cluster. any other ideas if that wont work?

I read on a Taurus website that a couple of people have fixed this problem by removing the instrument cluster and cleaning the 2 plugs behind it.

We have the same problem with our car. Have any of you been able to solve this problem of the turn signals staying on and dash lights going out? Thank you.

It really sounds like an electrical connection that has become temperature sensitive - open when cold and normal above 40 deg F.

I'm a former electronic technician and here are some ideas based on circuit board failures I diagnosed and repaired where I worked. Sometimes soldered connections on a circuit board are "cold-soldered". That means that not enough heat was applied when they were originally soldered. Cold-soldered joints look dull; good solder joints are shiny - unless they are very old and have gathered some dirt. This problem causes connection failures later on - and they can be temperature-sensitive. The fix was to reheat the solder joint until the solder was bright, shiny and liquid. Then you let it cool until it was solid and rerun your tests.

So can tiny cracks in a circuit board, that don't fail at first but later on become sensitive to cold/heat/moisture/vibration/etc. Those can be difficult to find unless you can wiggle/bend the board and see if it gets better or worse.

In cars, ground connections are often made to the nearest metal surface and rust can cause electrical connection problems as the car ages. Vibration and heat over time can cause the wires' insulation to break down, wires to fray, etc.

We often diagnosed temperature-related problems by measuring resistance (with an ohmmeter or multimeter) while applying heat with a hot-air gun or cold with freeze spray (it comes in a can and can drop the temperature of something to way below zero.

I hope some of these ideas will suggest a way to troubleshoot your problem.

FIX= My 2002 Mercury Sable GS V6 3.0 had the same issue with the instrument panel not showing any lights and both turn signals being sold green. I fixed this by removing the dash and disconnecting the instrument cluster(YouTube). I cleaned both side of each of the connector ports with alcohol and lifted the contact prongs up. I did this with a very small screw driver on both cables to all the prongs. The prongs seemed to relax over time and need to be lifted up so they make a better connection with the instrument panel's flexible plastic circuit board. While having the instrument cluster off I took the time to replace all 5 bulbs as well, just turn each connector counter-clockwise and pull out the bulb($6.50 for 2@autoparts store).Reinstalled and everything worked like new, hope this helps!