Air conditioning problem on recirculation (See Post #7)

Not cool. (grins) To me this sounds like a problem for the dealership.

 

Not sure this will change your situation, but I have noticed that airflow from the top vents increases when you switch from Front Only bias to All Rows. Yet, yours sounds like an actual malfunction/broken part based on your description...warranty coverage?

 

Sorry to hear of that problem. Quite a few issues with this generation four Prius. They may have to tear apart your dashboard to find the broken flapper. I usually always leave my recirculation button in the on (closed) position, to keep from sucking dust and dirt into the vents and cabin. But on occasions when I switch to open, I never hear any sounds. Air flow is good from top vents.

On a side note, i would replace the cabin pollen filter at least once or twice a year. mine was filthy after 12 months.

 

When you next visit the dealer, I’d suggest starting with a clear description of the trouble, which the service advisor should enter on the repair order something like this: “Customer reports very low airflow from vents when recirculation/fresh switch is set to recirculation. When switch is set to fresh, airflow is normal.” You’re not asking them to solve a problem with the blower, with the temperature, or with the sounds that you hear, so I wouldn’t mention those unless the service advisor asks.

From your description, it seems clear that the problem is in the Air Inlet Control function. There are two dampers, the Air Inlet Control Damper (Upper Side) and the Air Inlet Control Damper (Lower Side), which are part of the Blower Assembly (87130-58101) but operated by the No. 1 Blower Damper Servo Sub-Assembly (87106-58050, now 87106-0E130). The problem could be elsewhere—in wiring or an ECU, for example—but you do seem to have some control over the dampers, so these causes are less likely than a broken part or a defective servomotor.

If the dealer can’t find the problem, ask if they’ve followed the troubleshooting procedure in the Repair Manual (available to you by subscription to techinfo.toyota.com) for diagnostic trouble code (DTC) B1442/42, Air Inlet Damper Control Servo Motor Circuit. This applies even if the DTC has not been stored, since the same procedure is also referenced in the Problem Symptoms Table under “No inlet air control.” Unless there are other DTCs, this will require full disassembly of the dashboard, just for diagnosis.

I’d probably leave diagnosis to the dealer, at least for now, but if you want to check for DTCs yourself, there is a built-in diagnostic check mode in the air conditioning control assembly that does not require a Techstream diagnostic system. Here is the procedure to access this mode, which comes from the Repair Manual under Vehicle Interior: Heating / Air Conditioning: Air Conditioning System: Diagnosis System:

INDICATOR CHECK
(a) Turn the power switch off.
(b) Turn the power switch on (IG) and press the air conditioning control assembly AUTO and recirculation/fresh switches simultaneously within 5 seconds.
(c) The indicator check is automatically performed when panel diagnosis is activated. Check that the indicators light up and go off 4 times at 1 second intervals continuously.

HINT: The sensor check automatically starts when the indicator check is completed.
Press the OFF switch to cancel check mode.​

SENSOR CHECK (DTC CHECK)
(a) Perform the indicator check.

HINT: After the indicator check is completed, the system enters DTC check mode automatically.​

(b) Read the DTCs displayed on the display.

NOTICE: In sensor check mode, which is automatically entered after indicator check mode, troubleshooting may be partially performed. Be sure to perform the sensor check again.
HINT: Refer to Diagnostic Trouble Code Chart for details of the codes.
• When there are no problems, DTC 00 is output.
• As an example, the illustration [not reproduced here] shows that DTC 12 is output.​

(c) If the DTCs are difficult to read because they change automatically, Push the TEMP up switch to display the steps one at a time so that they can be read easily. The items are displayed step by step each time the TEMP up switch is pushed.

HINT: Press the OFF switch to finish panel diagnosis.​

(d) Clear the DTCs.

(1) During the sensor check, press the front defroster switch and rear defogger switch simultaneously.​

Here is a list of some DTCs you might find; the Repair Manual gives complete explanations and troubleshooting procedures:

B1411/11 Room Temperature Sensor Circuit
B1412/12 Ambient Temperature Sensor Circuit
B1413/13 Evaporator Temperature Sensor Circuit
B1423/23 Pressure Sensor Circuit
B1441/41 Air Mix Damper Control Servo Motor Circuit (Passenger Side)
B1442/42 Air Inlet Damper Control Servo Motor Circuit
B1443/43 Air Outlet Damper Control Servo Motor Circuit
B1448/48 Passenger Side FACE Servo Motor Circuit
B1449/49 Rear Air Outlet Damper Control Servo Motor Circuit
B1471/71 A/C Inverter High Voltage Power Resource System Malfunction
B1472/72 A/C Inverter High Voltage Output System Malfunction
B1473/73 A/C Inverter Start-up Signal System Malfunction
B1474/74 A/C Inverter Malfunction
B1475/75 A/C Inverter Cooling / Heating System Malfunction
B1476/76 A/C Inverter Load System Malfunction
B1477/77 A/C Inverter Low Voltage Power Resource System Malfunction
B1497/97 BUS IC Communication Malfunction
B1498/98 Communication Malfunction (A/C Inverter Local)​

If you do find any DTCs, don’t clear them, since the dealer should also see them. Indeed, this is the main reason for you to check—if there are stored DTCs for which the Repair Manual gives troubleshooting procedures, it’s harder for the dealer to dismiss your concern or claim that everything is normal.

 

The purpose of the cabin air filter (which you serviced) is exactly to filter "dust and dirt" from entering the cabin. Keep it fresh, and you'll be fine. More importantly, I believe there is a concern about using recirculation in heavy urban traffic, where CO2 from vehicle exhaust becomes "trapped" in the cabin and you end up breathing too much of the fumes. Better to keep a supply of fresh air entering the cabin.

 

Good! May I share your joy that it, whatever 'it' was, has gone away and for whatever reason it doesn't come back.

 

Hi everyone, this is my issue. So I noticed my A/C was not blowing as cold as it once used to. Like most folks I went and picked up a bottle of AC Pro to recharge the AC. Followed all the instructions per the bottle and it read “low” so I attempted to recharge it over and over again. I think I used about half the can. The AC blew nice and cold and left it running for about 30 mind while I was cleaning the interior. I noticed the fans kick on and then shut off about 2-3 seconds and cycle back on. AC blows hot air and switch the outside air on and switches back to circulate air and will do that repeatedly after a couple seconds.