P1121 - Coolant Flow Control Valve Position Sensor Stuck - 2007 Prius

Hi Everyone,

It's been a long week for me and my 2007 Prius. Brought it to the dealer after receiving my first ever CEL. I have 222,000 miles on the vehicle. They tell me that it will be $58.00 to diagnose issue. They call me an hour later and tell me that the error was related to the ECU and that they would need to "pin point" troubleshoot more and that it would cost an additional $164 to continue diagnosing. $222 later in diagnostics, they tell me that the error is P1121 - Coolant Flow Control Valve Position Sensor Stuck. The cost to fix - $533.00. The a/c was also blowing warm when the CEL came on. They checked that and told me that the compressor was "breaking up." Cost to replace $1,600. Then they call me back to tell me that my 12V battery died. Cost to replace $300. They asked me if I had problems with starting the vehicle. I said never. Never had any issues with the car in 222,000 miles. Well, told them to replace the battery (no choice) and the car is 5.5 years old in Florida heat so it was ready to die. Very suspicous that it died while they had the vehicle, but what can I say. Told them to not repair the coolant flow valve or the a/c until I could investigate further on my own. CEL is now off. The a/c is blowing cool again. Still had to pay the $222 diagnostics since I didn't have them repair the coolant valve. So $570 for a battery and diagnostics.

Two questions:

Is a $222 diagnostic charge reasonable? I mean could Auto Zone have scanned for free and received the same error code of P1121 in a matter of minutes or did the dealer really and truly have to commit more time for a "pinpoint" scan, etc.? I feel like I screwed up bad ($222 error) by not going to AutoZone first!

Second, do you think the Coolant Flow Control Valve Sensor being stuck could effect the cooling (A/C) system? Since the light went off, the A/C blows cold. I should add that about three weeks ago, the CEL came on one day and went off (the very first time ever). The A/C was blowing less than cool at the time. They purged the system and added dye to check for leaks. They said that it needed freon (or the new substance - don't know the name). Cost $90.00. No leaks. Now, three weeks later, they say the compressor is "breaking up." All sounds crazy to me. What does "breaking up" mean?

Sorry for such a long post, but whoever has read this far, has the knowledge to add thoughts, and feels like doing so, could you please post a response? I am thinking of going to trade mine this weekend for about $5,000 and get a 2012. I am worried that this is the start of problems for me on a vehicle that has an excellent service history!

Thanks!

Read more: http://priuschat.com/threads/on-board-diagnostics.59699/#ixzz25Axtl29M

 

They did add the freon about three weeks ago. I'm going to keep an eye on it. I bought a thermometer and the air vents are blowing cold now. I will wait to see if the CEL comes back on. Who knows, if it is a vehicle coolant issue, maybe that's what causing the A/C to blow warm when the coolant valve fails? Seems like the valve getting stuck is intermittent. Thanks for taking the time to post.

 

Okay, thanks. I did check the level because someone else said the same thing you did. Low coolant? Since they changed the 12V battery last Thursday, the A/C has been blowing cold and the CEL has stayed off. Fingers crossed!

 

I will keep everyone posted. The CEL came back on yesterday. I ran down to the AutoZone. Within 10 seconds, they diagnosed it as P1121. It went off after they checked it. It has been off all of today. I will let you know if it comes back on. If it does, I plan to go back to Toyota and have them repair it minus the $222 diagnostic fee that they charged me. I do want to get it fixed. This is the first real issue I have had with my Prius that has over 222,000 miles.