My fans work fine. L/H on at 190 and R/H when needed. My question is this: Does the L/H ALWAYS go on when A/C switch is turned on? I remember reading that left fan is controlled by the coolant temp switch and ac high pressure switch in parallel. It will not necessarily come on by turning on the ac, unless pressure is too high. Right is controlled by ecu, based on coolant temp & oil temp. Can anyone comment?
I would tend to aggree with you. Now that the external temp is high, I also noticed that the left fan is (always) starting right after I fire the engine. So since the engine water hasn't had enough time to warm, and that the AC is also starting-up right from the beginning, I would tend to aggree with you. This is only based on my experience. I did not read anything about a potential control of the fan based on the AC pressure. Bye, Christophe.
That is correct. Regardless of my coolant temp, the second I switch on my A/C my fan comes on simultaneously.
A couple of questions about 355 fans .... a) How can you test if the RH fan is working? I've never heard mine ... LH yes ... but RH no. Oil temp. never seems to 'overheat' so maybe I just never reach the RH 'fan on' temp. b) In Texas ... currently at ~ 100 deg. when driving, the temp. is normal ... car never seems to overheat. But when stuck in traffic that needle goes up pretty quickly ... but never into the red ... to the point I'm nervous about driving in mid-day heat and in town. I thought about: c) Taking out the thermostat in summer to create a better flow. d) Wiring the RH fan into the LH so both come on with coolant temp. ... my gut feel is that (d) should not be necessary .. so I'm back to (a) ... how to test the RH fan.
Peter - The R/H fan may be working but it is not as noticable when it kicks on as the L/H fan. It's in the 90's here in FL and here is how I check mine. Drive the car and let it warm up to normal operating temp. Then just park it with the engine running. You may have to let it idle for up to 15 minutes, the L/H can't keep up with cooling the engine, the R/H will (and should) come on. If it's near 100 in TX and should not take very long for the R/H to come on. Re: my first comment on this thread it seems to be true that the L/H is also hooked up to the the a/c high pressure. For some reason I thought the fan always came on as soon as you hit the switch for the a/c. What happened is I turned on my a/c and no fan. The compressor came on, it blew cold, but I did not hear the fan come on. Thought maybe relay, but the a/c and the the water temp sensor share the same relay. Anyway, I keep my a/c temp at the 12 o'clock position (72?)....and when I crank it down to max cold, then the fan comes on.... So bottom line is that the cooling fans do not automatically come one when the switch is turned on...Sorry did not mean to ramble on...
