Climate System Problem (Thought to be MFD Problem)

[losaltosprius]

I have had a problem which I thought appeared after the SSC-40D reprogramming. I described it here in September in a discussion about Celsius versus Fahrenheit display:

Sometimes (seemingly at random) upon starting the car up, the outside temperature in the upper right of the screen comes up in Celsius even though the ODO is set to miles.

A workaround for what is clearly a bug is to select the "Climate" display. The Outside temperature will be on the upper left, still in Celsius. However, if you push the "Climate" button again, you will get the Energy Monitor display with the Outside temperature in Fahrenheit.

When this happens, the internal temperature is reset to 75 degrees Fahrenheit and must be reset by hand.

After seeing the recent descriptions of the problems with the Multifunction Display (MFD) resulting in TSB EL002-05, I demonstrated the problem at my dealer. They ordered a new MFD (which arrived in three days) and replaced the MFD. See TSB on Multifunction Display - EL002-05

My dealer did an excellent job: no rattles or scratches. I now have the added functionality of being able to toggle the Energy and Consumption screens via the steering wheel info button.

Unfortunately, last night (one day after the switch) the screen came up in Celsius again.

Thus it probably was not the MFD (which probably cost Toyota a bundle to replace.)

Any ideas?

[DanMan32]

Actually, others have reported hearing the MFD is now $400 with exchange, not that anyone had to pay that.

Anyway, if it wasn't the MFD, then it may be the AC amplifier AKA AC ECU.

What they could try first is reset/toggle the AC customizable configurations. Sometimes toggleing things back and forth fixes little glitches like this.

[losaltosprius]

Thanks for the tip. This is obviously not life threatening, so I'll wait until I have to go in for a regular service.

As an old computer person, it smacks of some paramter RAM not maintaining settings. I hadn't seen anyone else describing a comparable glitch on this or other Prius groups and, as I said, the TSB EL002-05 was too good to be true! The description convinced me as well as the Prius tech at Stevens Creek Toyota in San Jose, CA. In any event, after the replacement I have the additional functionnality described in my original message, and a rattle in the left heater vent has disappeared.