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Have a 2011 Toyota Sienna V6 with a complaint of AC not cooling. Upon checking complaint, the pressure readings ambient temperature is around 80-90 psi, when turning vehicle on AC on, nothing happened. Stayed the same reading, noticed the clutch not engaging. Looked at the different modes and AC mode is on but no cool air. I tried to command the clutch to make sure it was working but on my snap on scan tool the option was AC clutch relay, i tried that and nothing happened. So I decided to test the AC clutch directly and it worked with a power probe and noticed the AC condenser fan not working either, power it directly and didn’t work, I’ll need to replace fan. So kept on looking around and wasn’t able to find an AC relay, all fuses were good. Would anyone point me out to where the relay may be, all I found in the relay box was a long looking white module in the middle but doesn’t tell me anything of what it is.
I looked at codes, no present or current code, found a history code of B1429. Something related to a flow sensor, when I looked at the sensor voltage it was showing between 0.70 - 0.72 v.
Does someone knows about this system that can point me in the right direction and also some information as well as an electrical schematic?
Please email me directly to following email and also I’ll greatly appreciate your help
Joshm1975@outlook.com
Josh, definitely follow the flow sensor. Your reading of .7V is too low to allow for compressor engagement. The flow sensor must read above 3.9V for the A/C Amplifier to send the compressor request to the ECM. That's why you're not seeing compressor engagement.
The flow sensor is mounted to the compressor itself. Three wires. 5V, signal and ground. The signal circuit uses a pull down bias and will show near 5V when unplugged.
If the flow sensor circuits test correctly, then the flow sensor has failed. The sensor is sold separately by Dorman and others, but compressor replacement is usually the better option.
Also check out this thread for further information. There's a "work around" available.
