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Discussion Starter · #1 · (Edited)
When I turn the AC on, only condensor fan run. I heard that both fans i.e radiator and condensor fans should run when AC is on.

I know 100% my radiator fan is working, as it run when the engine got hot.

Should both fan turns on when AC is switch on ?
 

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Typically, the coolant needs to reach a temperature of 199 °F (93 °C) before the radiator fan should turn on. There may be instances when both will run, but I'm not seeing it spelled out in the service manual anywhere and the problem you describe is not one of the symptoms for which it provides guidance. This suggests what you are potentially seeing is normal operation. You could check the A/C relay just to be sure, but it may be a waste of time...
 

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You do have a problem. These guys are wrong.

Both fans should come on with the AC on.

This issue will manifest itself come summer time. The vehicle will over heat and or there will be poor performance from the AC system.
 

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After looking at the correct part of the service manual you'll want to diagnose the Radiator and A/C Condenser fan circuit using the process outlined on 21-35 (page 1625) of the service manual: http://www.mediafire.com/file/dwm2qkmzy2n/%28LINKED+Edition%2902-06+Acura+RSX+Shop+Manual.pdf

I don't believe this will cause the vehicle to overheat since you mentioned the Radiator fan does come on once the vehicle has warmed up, but it may negatively impact A/C performance.
 

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Correct, if only the radiator fan runs w/ the A/C off during high ambient temps, and the car is stopped, it is possible it could overheat. If the car is moving I'd suggest the potential is marginal, if any at all. Since it's not noted whether both fans run when the A/C is off and the ambient temps are high it's hard to say one way or the other.
 

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Correct, if only the radiator fan runs w/ the A/C off during high ambient temps, and the car is stopped, it is possible it could overheat. If the car is moving I'd suggest the potential is marginal, if any at all
Agreed. I wanted to edit my post to put"at idle" but didnt see an edit button.

Since it's not noted whether both fans run when the A/C is off and the ambient temps are high it's hard to say one way or the other.
The wiring diagram, written description of the the cooling fan circuit, and scan data show that they do. (along with 21 years of experience in these matters)

Ive not used a printed service manual in over a decade,so Im not sure how to point you to that information.
 

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Agreed. I wanted to edit my post to put"at idle" but didnt see an edit button.



The wiring diagram, written description of the the cooling fan circuit, and scan data show that they do. (along with 21 years of experience in these matters)

Ive not used a printed service manual in over a decade,so Im not sure how to point you to that information.
To clarify what I meant was that, since spacemaster doesn't make note of whether both fans run when the A/C is off and the ambient temps are high it's hard to say one way or the other. The diagram definitely shows that when operating correctly they should in that specific situation.
 

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Quick question you guys. You're saying that the A/C fan should come on with the radiator fan at high ambient temps even with the a/c off, right?
Do you mean higher than the 196-203 temp range referenced in the manual?

I haven't had any issues with temps during the summer even in stop and go traffic. The a/c does seem like it doesn't blow as cold, though.
 

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Should have started with this, but did you check the No. 1 (30 A) and No. 4 (20 A) fuses in the under-hood fuse/relay box, and the No. 14 (10 A) fuse in the under-dash fuse/relay box?
 

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Quick question you guys. You're saying that the A/C fan should come on with the radiator fan at high ambient temps even with the a/c off, right?
Yes.

Do you mean higher than the 196-203 temp range referenced in the manual?
That is engine temp ,not ambient. The thermostat is in place to regulate engine temp, however when it cannot do so alone,the fan comes on to help out. When it is very hot outside(ambient temperature) this increases the need for additional heat shedding.

I haven't had any issues with temps during the summer even in stop and go traffic. The a/c does seem like it doesn't blow as cold, though.
Have it checked out.
 

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Discussion Starter · #18 · (Edited)
To clarify. I dont have over heating either driving or stop idle.

When I changed my car coolant, I noticed only radiator fan turn on when egine warm (AC is off) for around 30 secs, then stop. Then it turns on again after engine getting warm again. This is exactly as described in the workshop manual.

Turn off the car, few hours later... While the engine is much much cooler, I turn on the AC, I only saw AC fan turn on, not both.

I thought both should turn on.

Yes, I check all in manual to test relay, jump, etc. Thay all work as individually... no where in the manual describe both fan have to run and how to test and fix.

I am confused.
 

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So it sounds to me like a little bit of hypochondriacal. If you aren't having issues with overheating it's probably not a major issue, if any issue at all, and A/C not blowing as cold could just be low refrigerant, decreased performance of the condenser due to age or a number of other possibilities.

Considering the ECM/PCM is capable of turning the radiator fan and a/c compressor fan on with the a/c off to improve engine cooling during high ambient temps I would tend to think a similar approach may be employed when the a/c is on, i.e. if the a/c is struggling to meet demand with just the a/c compressor fan then turn on the radiator fan. It seems logical, but without knowing the firmware or what logic gates were employed in the circuitry I can't say whether this is in fact how it works.

If you're really concerned about it I recommend following DC1FVER's advice and have it checked if only to put your mind at ease.
 

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Discussion Starter · #20 · (Edited)
I dont know if i should concern or not. The manual does not list that sympton, and also does not show me how to test and check when both fans not runing at the same time.

I guess i leave it as it is for now.

Can anyone here confirm by turn their car (Acura RSX, of course :))AC on and see if both fans runs ?
 
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