A/C compressor not engaging

BLESSING EWOBOR

MEMBER
2010 TOYOTA SIENNA
6 CYL
AUTOMATIC
134,523 MILES

Good evening, the vehicle compressor is not functioning when the A/C switch is on. The blower fan is functioning, the system has enough pressure, when I connected power to the compressor directly from the battery, it function so the problem is not the compressor. Please Could you help me with the A/C circuit diagram?

9 Replies

JACOBANDNICKOLAS

MECHANIC
109,885 POSTS

Hi,

I attached the wiring schematics for the entire HVAC system. I highlighted two wires. One is +voltage to the clutch, which is where I think the problem is. Take a look through the pics.

In my manual, the schematics are two pages long. I cut each in half to make it more readable for you. I did overlap them and keep them in order.

Here is a link that you may find helpful:

https://www.2carpros.com/articles/how-to-check-wiring

Let me know what you find or if you have other questions.

Take care,
Joe

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Wednesday, December 23rd, 2020 AT 11:46 AM

BLESSING EWOBOR

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687 POSTS

Hi, from the diagram, how will I know the input needed by the A/C control assembly to ground the control circuit of the relay?
Is the A/C control assembly same as the A/C control module?

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Monday, December 28th, 2020 AT 10:57 AM

JACOBANDNICKOLAS

MECHANIC
109,885 POSTS

Hi,

They are one and the same. As far as checking, I'm not completely understanding what you are asking. If you are referring to the relay itself, it will see 12v. Is that what you mean?

Take a look through this link and let me know if it helps in any way:

https://www.2carpros.com/articles/how-to-check-an-electrical-relay-and-wiring-control-circuit

Let me know.

Joe

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Monday, December 28th, 2020 AT 10:37 PM

BLESSING EWOBOR

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687 POSTS

It seems that the A/C control assemble is not completing the circuit, the compressor is not engaging. I wanted to trace the circuit.

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Tuesday, December 29th, 2020 AT 8:22 AM

JACOBANDNICKOLAS

MECHANIC
109,885 POSTS

Hi,

Take a look at the attached pics. They are from the schematic for automatic climate control. I had to cut them in half to make them readable. However, I did overlap them for you to follow.

If you don't have the automatic climate control, let me know.

Joe

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