radiator fans not working

Hi all, I have a 92 maxima GXE. I noticed my AC not blowing cold air. I took a look and found that neither radiator fans are working. I believe one cools the radiator and the other is for the ac. I cant imagine both fans can go bad at the same time.

I tried the following steps suggested in the Chilton's manual.

- shorted the fan relay and measured the volatage to the fan harness. It didnt show any voltage coming there.

- checked the fusible links. They looked ok.

- I also checked the ECU code and it flashed 55 (no problem)

I have not done a thorough checkup. But I was wondering if there are there other ideas/causes for the fans to stop working. Is my ac really dead or is it because the fan is not working. I dont want to take it to a mechanic if I can at least diagnose the problem.

Thanks for any tips.

Sunny

Reply to
sunny
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It sounds like you either need a quick course in basic electricity/electronics or a friend who has some background in electricity.

It should be a simple circuit tracing exercise if you have a circuit diagram.

Without a wiring diagram, it's more difficult and some of us have a hard time tracing out what is going on without that crutch.

Lacking that you'll have to bite the bullet and have a shop work on it. Your own time is probably worth something isn't it??? How much time do you want to spend trying to figure it out when you might be doing something else that is productive and which you have the experience and background to do?

sunny wrote:

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Don't Reply to this address

I didn't want to make any assumptions here. Are you sure the motor is warm enough for the fan to run? I believe for that year, the fan only runs when the motor needs additional cooling. Of course, if you need air conditioning, then it's probably warm enough for the fan(s) to run. What does the temp gauge say?

Reply to
ppointer

---snip---

Does the A/C blow cold air at steady speeds above 35 mph? If so, then your fans have a problem. If not, your A/C system is probably low on refrigerant, and neither the compressor nor the fans will run.

Reply to
James M. Blaschak

According to Chilton's they say both fans must rotate at a low speed when the ac is switched on. This isnt happening

Reply to
sunny

The AC is not blowing any cold air at any speed. I guess I will check the fans after the car is warm.

Reply to
sunny

It is unlikely that both fans are bad. If they don't come on when you switch on the AC, then the problem is in the switching. Either they are not getting power, or the switch is bad. First thing to check is fuses and breakers, then connections and grounds.

I think it will be easier to solve the problem of the fans not coming on with the AC before looking into whether they work when the engine is warm. Switching on the AC should make the fans come on regardless of engine temp.

Reply to
E. Meyer

Thanks. I think it is likely a connection problem. I guess I will trace it. I am only hoping that the ac not blowing cold air is a symptom of the fans not coming on and not a problem with the ac itself. Thank to all who responded.

Reply to
sunny

The compressor doesnt seem to be engaging. I see no voltage being delivered to the fans. I followed the diagnostic procedure in Chiltons manual -

  1. Start engine, turn on ac. Both fans must rotate at low speed - FAILED, go to next step
  2. Stop engine, disconnect fan relay-1 and jumper relay terminals 3 and 5. Disconnect both fan motor harness connectors, Turn ignition switch on. Check voltage between terminal a and ground. Must get Battery voltage - FAILED, go to next step
  3. Check "GY" fusible link - I assume this is the fusible link attached to the positive battery. Tested ok Check "R" fusible link - I assume this is the 45 amps (red) fusible link in the fusible link box. Tested ok Check Joint Connector (J/C) E51 - I dont know how to locate this or what it looks like. Anyone know ? If step 3 were ok, then it says to repair the harness or connectors. I dont know which connectors they mean.

I also checked the fuses in the car (dash compartment) are ok.

From the wiring diagram, it looked like the Battery voltage is directly fed to the fan harness via the above fusible links, J/C, relay. Is the ECU involved in any way to get voltage to the fan. I am assuming the ECU is only involved in the control aspect. The voltage part is just a feed from the battery. If so, could it just be a wire continuity problem ? Kinda unlikely for wires to both fans to go bad.

Reply to
sunny

You say the compressor is not coming on? Trace that first, all the way back to the AC switch on the dash. The fans don't go on unless the compressor engages.

Most compressors have a low charge cut out that keeps them off if there is nothing in there.

Reply to
E. Meyer

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