"Check the connection of the Air Conditioner" message

This is a new one to me. Our 2G 2004 Prius with 150,000 miles just popped up this message this afternoon. AC not working, car seems fine otherwise. I peaked under the fuse box, pulled a few that I thought might be related, but didn't find any obvious culprits. Didn't see any obvious wires/cabled broken or disconnected, but can't say it was a thorough search. Anyone seen this? Anyone know if this is an easy fix or if there is a specific fuse I should be checking?

Found this thread, I suppose it could be a bad MFD...

 

Just FYI, the Autobeyours links are helpful (if needing a bit of an update as the photos don't load). Prior to sending in the MFD he points out that one should disconnect any iPhone or XM accessories connected to the MFD. I did disconnect my XM, but the problem persisted. He also says to check the battery and replace it if low voltage or more than 4 years old. I used the diagnostic screen to do this and found it slightly low (resting voltage at 12.0v, Under load 11.9v, 13.9v in Ready). So I've ordered a replacement to see if that makes a difference, though I'm skeptical it will make a difference.

If the new battery fails, I'll send in the mfd for repair.

 

12 volt battery replaced this am, issue persisted. MFD removed, boxed and ready to ship to autobeyours.com in the morning.

 

Update. Got my MFD back from AutobeYours and reinstalled it today...and the problem persists. I've tried to reach Steve at ABY but so far he hasn't gotten back with me. I think I'm doomed to take it to Toyota. It's getting quite cold out and we've got to have the climate control working. Sux as I was really hoping this would save me a lot of money, but it's looking like it's going to cost me a lot.

 

Hey Patrick, thanks for your reply. As the weather got worse I broke down and swallowed my pride and took the car to the local Toyota service center. $58 later they guy found a 10 amp AC fuse that was burned out and the cause of the whole issue! So It cost me around $350 in an MFD repair that wasn't needed. I did learn to pull the dash apart though. Apparently the burned fuse was NOT easily accessible in the fuse box...I had checked them. But I don't know where the burned fuse was located so I can't speak on that with certainty.

Lessons learned? Not sure...I think the fact that the MFD worked for everything except the climate control is probably the key clue that this was NOT MFD related despite the similar warning. Sometimes the "check AC connection" really means to check the AC and not to assume it's the MFD that also shows the same warning.

 

I'll have to look...I bet that's where it was, I just looked at the box under the hood...damn, would've been so easy to fix myself. I haven't seen the invoice yet, my wife and kid picked up the car, but I'll try to take a look and report back the details...maybe take a photo of the new fuse for future reference.

 

And Patrick, as is typical, nails it. There is a fuse box in the cabin, just under the dash by the steering wheel IIRC, and that is where the 10A HTR AC Fuse was located that was replaced. $1 fuse, total cost to me about $400 with an unnecessary MFD repair. Hope someone else can save about $399 or more by finding this thread someday.

*Edit- Forgot that I also replaced the 12v battery at a cost of around $160...So $560 total spent for a $1 fuse!!

 

Well, the AC failed today...assuming the fuse blew again. Makes me wonder if there's an AC problem causing that to happen. Frustrating.

 

Service tech called and went into a long winded explanation about a "second water pump for the hybrid system" that seems to be causing the fuse to blow. I'm pretty sure he's just referring to the coolant pump that Patrick pointed out as a likely cause and that I suggested that they check first thing..of course they messed around all day until finally checking that. In any case, it's going to be about $900 to replace it and it takes a couple days to get the part. So maybe will have our car back, in working order, by Wednesday afternoon.

 

Will do, I requested they give me the parts. I would love to think I could have found a salvaged part and done the work myself, but it's just not realistic that I would have the time or know how to do it. I suspect you need the scan tool to circulate the coolant properly to refill anyway.

 

$1000 later & I think I'm fixed. The $700 part looks like it should cost $35. It is about 7-8" long & 2" diameter excluding the mounting bracket.