Electric cooling fan issues. ?
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  1. #1
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    Electric cooling fan issues. ?

    It finally warmed up here in South West Washington, so the AC was pressed into service, only it didn't. The AC would cool better (not great) at close to highway speeds (short spurts to 50). It seems the auxiliary electric fan is not working. I does not turn on when I hit the auto button, which usually turns on the ac and aforementioned fan. What would you fine Passat World folks suggest as a way to diagnose the actual problem?

    I have a V6 GLX wagon with Climatronic.

    I have not done an jumper action to test the fan. Throw me a bone on that.

    I have no CEL action currently.

    Vv

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  3. #2
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    you might have a stuck relay. I had the same problem except my fan stayed on the whole time. just take it out and put it back it, hopefully that works.

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  5. #4
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    No click to relay 267, any thoughts? I put my finger on the relay, turned the climatronic from econ to auto and now click. Am I on the right track?

    VV

  6. #5
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    PLEASE chime in.

    I replaced relay 2 what ever. So is it the coolant temperature fan switch or the coolant fan control module. The coolant fan thermal switch should be on the left lower side of the radiator on the lower coolant hose. The control module is located next to the blue vacuum reservoir on the front left side of engine compartment.
    What are the real names for these parts.

    Please chime in


    VV

  7. #6
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    Did you check fuses for the fan and the fan control module? Check the Climatronic for codes by pushing econ and recirc at the same time. Then push the red heat up button to scroll through the codes. Write down and post. When you get to 000 you are done. A 444 is no problems.

  8. #7
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    Thank-you.

    Will do when I get a chance.

    I checked the larger fuses in the box. Which location? Are fuses in the fuse box responsible for the electric engine cooling fan? Does the fan control module have a fuse? How does one check the fan control module?

    VV
    Last edited by ViewVariant; 04-22-2008 at 06:32 PM. Reason: additional questions

  9. #8
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    The 40A (S42) cooling fan fuse should be on one of the relay panels. I don't know where the control module fuse (S51 - 5 amp) is located. There are only 44 positions on the fuse panel. Look on the fuse panel for 5A fuses and check them with an ohmeter.

    Get the codes from the climatronic. It should tell you whether, the module is bad.

  10. #9
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    So there is a fuse for the fan control module. Ok, thank you. The wife has the car so, can't pull codes at moment.

    Thanks again, will let you know.

    VV

  11. #10
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    ANY IDEAS?

    I pulled the climatronic codes today
    256
    4f7
    448
    4fa (4?)
    318
    000

    Any help?

    Checked all the 5 amp fuses in the fuse box. Found no 40 amp fuses in the fuse box behind the panel on the dash. Is there somewhere else to check?

    Vv
    Eric
    Last edited by ViewVariant; 04-26-2008 at 09:25 AM. Reason: added title

  12. #11
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    Any Help

    I would hate to have to go to a dealership. Any help?

    VV

  13. #12
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    256 Hex = 598 decimal = solenoid bad
    4f7 = 1271 = temperature regulator flap motor (V68)
    448 = 1096 = switch locked ??
    4fa (4?) = 1274 = air flow flap motor (V71)
    318 = 792 = a/c pressure switch (F129)

    Check all the fuses. Fuses 5 and 25 are on the fuse panel. Fuses 51 and 42 should be on the 8 position relay panel. You will have to remove the lower part of the dash under the steering wheel to get to them.

    Code 792 could be insufficient R134a, bad switch, bad wiring, or insufficient engine cooling (fans not running might cause this). But I don't see any codes for the fans. So, you might want to check the refrigerant level.

    The flap codes could be wiring, bad solenoids, bad position sensors. The two flap sensors do share a common 5 volt source. Also, when you push recirc do you hear a flap moving? Do you get heat if you set the target temp to max? If so, maybe the flaps are okay. You need a VAG-COM to run diagnosics on the flaps.

  14. #13
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    Thank you.

    VV

  15. #14
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    The 40A fuse on the relay panel was good, as was the 50A

    The 5A fuse on the relay panel also fine.

    Also, I you push recirc do you hear a flap moving, it seems that flaps move. I do you get heat if you set the target temp to max.

    Have I really checked the correct relay? Which one is it?

    Any other easy ideas?

    VV
    Last edited by ViewVariant; 04-29-2008 at 06:18 PM. Reason: added relay question

  16. #15
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    As far as relays to check, there is the a/c compressor clutch relay and the fan control module.

    Since you are getting some cooling, the compressor clutch relay (relay labeled 267 in the number 3 position on the 13 positon relay panel) is probably okay. With the car running, you should be able to feel/hear the relay pick up and also hear the compressor clutch engage when the climatronic is calling for cooling (start the target temp at a high number and then push the blue cooler button until the a/c kicks in). Again, based on the fault codes it seems that the a/c pressure switch is probably signaling to the climatronic to cut the a/c off. So again you may want to have someone check the charge of the refrigerant.

    So the 5A and 40A coolant control module fuses check good. The coolant fan control module runs the electric cooling fan based on a thermal switch. You can see the switch by looking through the lower left grill by the radiator. The coolant fan control module is near the blue vacuum reservoir in the lower left front of the car.

    If you can pull the 4 pin connector off the thermal switch, you can jumper slot 2 or 4 of the connector to ground and the coolant fan should run. Slots 1 and 3 should already be ground. The ignition switch may have to be in the on position.

  17. #16
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    Still checking.

    I ran power to the fan from the wiring connection near the power steering resevoir. The fan spun up then. I will try the jumper trick.

    The fan control module, is that driver's side or passenger's?

    I did find the hidden fuses for the cargo area power outlets slash cigarette lighters. I had been looking for that fuse for 3 years.

    I have a switch coming for the lower radiator hose.

    The cooling fan is not coming on at any time though. Does that suggest the thermal switch? It could be both, low refrigerant and a faulty switch. ??

  18. #17
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    I did the Jumper trick, and the fan came on low and high. Engine running fan ran and fan kept running after ignition off.


    VV

  19. #18
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    At least you know the fan control module is good. The low speed switch should close when the coolant is between 198*F - 207*F and open when the coolant drops to between 183*F - 196*F. The high speed switch should close between 210 -221 *F and open between 196 - 208*F. I would think at highway cruising that neither switch would be closed. Usually, the fans come on in stop and go traffic or when it's extremely hot out. Also, I don't believe the thermal switch is a common failure.

    Maybe when it's hot out, jumper the fan on low or high speed and go for a ride and see if the a/c gets cold.

    My bet is still low freon or a bad pressure switch (that's the code you got). The only other test might be to pull the connector off the pressure switch and then jumper the connector slots 1 to 2. This would indicate to the climatronic normal pressure. If you do have low pressure, you don't want to run the compressor very long with low pressure. The switch is located under the passenger side headlight. I believe you will have to remove the headlight to get to it.

  20. #19
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    Great. But, the fan is never coming on. Does that lean toward thermal switch? Or, are those operations inter-dependent? (Freon pressure and temp switch)

    Thanks again.

  21. #20
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    Fixed!

    I put a thermal switch and no change. I did manage to swap it out without too much mess.

    Anyway, I bought a can of 134a with a gauge on it. I let the ac system suck it in and Voila!, the fan came on and the air got cold. The gauge registers right around 30 psi on the low side.

    In hindsight, I should have done that first. Oops.

    Listen to the Climatronic and check the refrigerant pressure first.

    Thanks for all the help Ken.

    VV
    Eric

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