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Overheating dashboard electronics

I have a Toyota Avalon 2001 in South Carolina.
When the dashboard multi-display reports a temperature >84oF, the clock and/or trip odometers reset, and other readings go blank.
When the car cools sufficiently, all functions resume (though clock time has to be reset).

The problem has been narrowed to the multidisplay module or its connectors.

Is there a way to keep the car interior cool when it sits unused in a parking lot?

I currently leave the windows open ~2in behind rain covers, installed last year, that prevent unpredictable thunderstorms from introducing mold through the partially openned windows.
I currently use a reflector in the window. Both of these observably drop the cabin temperature ~20oF ,
yet it is not enough.
I have tried a fan, powered by the car’s battery, but extrapolation from measurements indicates that before any
fan moves enough air to have significant effect, it will leave the battery too drained to start the car.
A solar panel powered fan generates more heat than it removes.

Is there a way to remove the expose (and reseat) the multidisplay connectors, by just removing the padding above the dashboard?

I have the service manual, but have not yet found how to get access to the multidisplay, without removing the seats, and all cowlings from the center console forward.

Thanks in advance for any suggestions,

This is the kind of stuff that sends many otherwise serviceable cars to an early grave…The part probably costs $800 and it takes 200 man/hours to change it…Some manufacturers use better designs where the instrument cluster can be changed in a half hour…Good luck with yours…

That’s a shame. Maybe you can find an instrument cluster for this at a junkyard and save some money. Automotive electronics are designed to operate at 120F+ Clearly the cluster has a problem.

Your not going to keep the interior cool enough this summer to get under the 84 deg limit. Your in the South. Without the Sun, the ambient temps will exceed this. With the Sun, the temps can reach 120 deg easy, even with all your precautions.

To get to the connectors on the back of the gauge cluster, the padded dash top is not removed, but the lower dash and front bezel is. You may also need to remove some of the center dash, as well. If you have the Factory Service Manual, it should spell out the proper removal method. If you have a Hayne’s or Chilton’s they are always very weak in this area, and you may need to determine how it comes apart on your own.

I’m willing to bet that your problem is electronic to the cluster, not to the connectors. These clusters are electronic digital and heat soak is bad for the chips that help control it.

Resolution:

Summary:
The Multi Information Display circuit board was removed and replaced with a refurbished one by a professional mechanic. Assuming the problem repeats in the next few years, I hope I learned enough to first try reseating the connectors myself.

History:
During 120Kmi service, the mechanic shop left the car outside with the windows up,
The multi information display overheated. They repeatedly denied that they had ever seen the multi information display fail in any prior car. They also insisted that in the past (the past that never occurred) the failure was always on the circuit board (supplier phone number and order form handy) and not one of the two connectors, i’d identified by symptoms and service manual. They estimated $550 for a refurbished circuit board, rather than $2200 for an entire new multi information display, and $150 for labor.

Detail:
When the board arrived 10d later, I brought the car back. They were kind enough to let me watch disassembly which they said only involved the dashboard (though they repeated that they’d never seen dashboard electronics failure before). I observed as the mechanic quickly performed what appeared to be Steps 27-30 from the service manual BO-93.

  1. Remove left and right Speaker Assembly Cover pulling two clips each rearward.
  2. Remove Upper Cluster Finish Panel pulling clips downward.
  3. Remove Lower Cluster Finish Panel pulling clips upward.
  4. Remove Cluster Finish Panel unscrewing two screws.
  5. Remove and disconnect Mulit Information Display.

Visual examination showed a circuit board with no visible signs of overheating. Traces were shiny through the unmottled and uniformly translucent green antioxidation layer.
No solder threads were seen, and all surface mount chip edges were aligned. The connectors were not available for examination before disconnection. The connector site traces on the board were shiny and only slightly scratched.

Contrary to the service manual images, the C&D male connectors were mechanically ganged. If C vertically expanded more than D, the link between them could served as fulcrum, levering D out of connection.

As the removal and replacement only took 20min, the actual labor charge was only $75. The actual board cost was $465, and state and federal fees were only $20.
As coworkers and friends indicate the problem will probably recur in the next 3 years, and having seen the removal, I hope at that time, to try first myself to simply reseat the connectors.