"Check the Connection of the Air Conditioner" MFD Warning?

hello!

my MFD isn't working. the screen shows: "check the connection of the air conditioner". actually, it will occassionally work but then not work for long periods.

the prius boards point to a bad MFD screen as the main culprit. so I bought a used one off ebay that the seller said worked, but the problem persisted.

problem solving:

1. the ebay MFD could've also been broken.

2. there's another issue that could be causing it? is anyone aware of another possible issue which could be causing this?

**note, it could be a coincidence but the problem began just after I had a new aftermarket hybrid battery in? I've had no issues with the car or battery otherwise. taken it on long trips so the hybrid seems to work fine. but thought potentially there could be a link between the hybrid battery and the MFD? shot in the dark! ;0

any thoughts on this greatly appreciated!

cheers john

 

hello...the 12v is almost brand new. and the cabin air filters have been replaced fairly recently as well. the screen doesn't work at all for the AC anymore. When it was of and on... the climate control worked fine. I could operate it with no issues. Then I'd park the car and try again an hour later and the same error message.

Btw.... I just tried a different replacement MFD from ebay and am getting the same error message.

 

thanks SFO...I'd been thru a bunch of search results on MFD. but didn't see the one about the culprit possibly being the AC ECU? will search more in that direction.

 

thanks...but again i've replaced the MFD with two separate ebay units and getting the same error message>

 

hi again....I didn't want to assume anything with the 12v. I just did a voltage check using the MFD and the battery readings were:

during test no accessories: 12.1 v
stand by mode? (pressed power again): 11.9-11.7v
engine on: 14.4v

do those look right? I do remember now that I've replaced the 12v battery a few times in past year. I assumed I got a bad one? not sure if there's an underlying issue that draining it?

 

actually have one and did a test this AM from the battery itself:

after sitting overnight: 12.41v
standby mode: 12.33v (slowly rising)
load test (headlights 20 sec): 12.26v
car on: 14.10v

 

cheers- i did a proper test w/ meter this AM after the car was sitting overnight. if I need to be at 12.6v with car off, i'm about .2 below that (see new readings below), could that little amount cause the MFD issue?

after sitting overnight: 12.41v
standby mode: 12.33v (slowly rising)
load test (headlights 20 sec): 12.26v
car on: 14.10v