2000 Toyota Avalon digital Odometer getting reset to 0 (zero)

My 2000 Toyota Avalon has been a trooper, never had any problem with it.
Recently though, the Odometer will show 0 and the speedometer needle will stay at 0 as well.
But when I go for a long highway miles driving (about 60 to 75 miles), both of them start working.
Then when I park the car for a while (more than 1 hour), both will stop working.
To make it even more bizarre, some mornings, both of them will work out of the gate!!!
But most mornings both odometer and speedometer just do not work at all for several weeks at a time…
Please give me some pointers if you know what the issue is and thanks!

This would be a good one for the show. I can just hear Tom saying “Doesn’t anybody screen these calls!” … lol …

This is a toughie. Something is amiss, that’s for sure. Your going to need more info to solve this yourself, like access to the car’s shop manual or at least some way to figure out how this all is supposed to work. Then you can eliminate the potential culprits one by one.

I guess if I just wanted to try something, I’d see if whatever measures the speed input for the dashboard gauges is connected and seems to be working. On some cars this is done electronically through the ECM, and on other’s there’s a cable from the transmission right to the speedometer/odometer.

The speedometer/odometer are electronically driven from the information the computer receives from the Vehicle Speed Sensor. This is done thru drivers for the speedometer/odometer on the back of the instrument cluster. If there’s no Check Engine light with a code indicating a problem with the VSS, then more than likely there’s a problem with the instrument cluster.

Tester

@mmsylla, I think I might know what’s going on, but let me ask you one question: I get that the display’s intermittent, but does the odometer tally up a believable number of miles, even while “stuck” on zero? For example, if the odometer read 88,000 miles when it went to zeros, and you drove around 200 miles with it out, does it display roughly 88,200 when it comes back online?

If so, here’s what I think is happening (and let me preface this by saying this isn’t anything more than an educated guess):

The odometer reading, and the speedo, are DISPLAYED on the instrument panel, but they are COMPUTED elsewhere (like one of you car’s computers). The computer then sends a signal to the dashboard cluster as what to display.

In your case, (I think), there is a poor connection from the computer to the dashboard. The computer is keeping up with the speed and the odometer just fine, but the data isn’t making it to the dash for some reason–like corrosion, loose connector, etc. That’s why I asked the question: if I’m right, the odometer should be as “correct” as ever.