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    Cooling Fans Not Working

    I'm having this problem on old Lola. She was working fine when parked over a year ago. Now finally after getting the entire car put back together from trading the parts between old and new Lola. The engine is running great other than the fact that the cooling fans aren't kicking on. I'm in need of some more troubleshooting help on this one guys.

    Cooling and AC Condensor fans aren't kicking on.

    - Test both fans by jumping directly to battery both are good
    - Test cooling fan relay by replacing it with the power window relay, power windows still working after the swap verifying that the relay is good
    - When jumping the fan switch connectors the fans don't turn on
    - Cleaned all grounds and reconnected them
    - Checked under hood and in cabin fuses both are fine

    I've torn apart enough of the car to track down all the wiring and all the connections are hooked up at this point. I'm just not sure what else to check into, and would like some direction at this point.
    Last edited by Rilas; 04-09-2018, 11:01 AM.
    MRT: 1993 Honda Accord SE Coupe (Lola)

    #2
    I had this same issue a while back with my car. It would come up to temperature fine & all. But the first fan would eventually not come on. I’d hit the ac and of course both would come on. A little later after I had some other issues with the temp gauge falling as I drive, I finally replaced the thermostat. Everything works great now. I can’t say exactly if that’s your culprit but it’s an idea.
    5 studded & leather clad - Praise The Lowered

    ~Mark~

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      #3
      A failed thermostat should show itself by jumping the fan switch connector, getting the fans to kick on, with the ignition in the II position. This does not happen, therefore even if my thermostat was failed, this should still kick the fans on. Something somewhere along the lines is preventing power getting to the fans at all.
      MRT: 1993 Honda Accord SE Coupe (Lola)

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        #4
        I love the electrical problems that are most likely tucked away somewhere under the hood or dash. Btw off topic, Rilas, when you took apart the dash do you remember if there is a separable under dash harness? I might need to tear apart a pap car. I’ve had my dash out three times and I’ve never checked this.
        5 studded & leather clad - Praise The Lowered

        ~Mark~

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          #5
          I've torn out the dash multiple times. There is one or two plugs that just plug into the in cabin fuse box. If you start to remove the dash you should see them moving around. Just unplug that, and then yank it out, Honda really did make it convenient to remove the dash.
          MRT: 1993 Honda Accord SE Coupe (Lola)

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            #6
            They are both controlled through the Radiator Fan Control Module which is mounted down near the fuse box at the driver kick panel. You say you checked all fuse? #2 in the under dash fuse box is listed as the most likely cause of failure of either fan to run.
            90 LX 4dr 5 spd 396,014 (sold 1/1/2022) - MRT: http://www.cb7tuner.com/vbb/showthread.php?t=201450
            08 Element LX FWD AT 229,000 - MRT: fleetw00d : 2008 Honda Element LX - CB7Tuner Forums

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              #7
              Alright I just double checked fuses.

              #2 "ECU" & #8 "Cooling Fan Relay" fuse in the cabin under the dashboard are both fine. Also double checked the fuse under the hood labeled as "Cooling Fan" which is good as well. Checked the connections into what I think is the "Radiator Fan Module", but I'm not 100% sure exactly which one that is. If it's what I'm thinking it is, it's fully connected.

              After doing so, I jumped the connection at the thermostat and tested the ignition, still no fans.

              The grounds that I verified and cleaned up are the engine harness ground at the thermostat housing, the ground bundle on the passenger side, the ground bundle on the drivers side, battery to chassis, and battery to transmission.

              Is there a ground I need to check inside the cabin?
              MRT: 1993 Honda Accord SE Coupe (Lola)

              Comment


                #8
                Make sure you actually have power at the module. I know you say you've checked the connectors and grounds. Have you actually checked the continuity of the wires between connectors and to the grounds? Try jumping across the module connections - if you get the fans to work, then the module is bad.
                90 LX 4dr 5 spd 396,014 (sold 1/1/2022) - MRT: http://www.cb7tuner.com/vbb/showthread.php?t=201450
                08 Element LX FWD AT 229,000 - MRT: fleetw00d : 2008 Honda Element LX - CB7Tuner Forums

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                  #9
                  Alright to verify, is it the block box sort of hanging down above the cruise control module?

                  If so I'll work on checking the connections and go from there.
                  MRT: 1993 Honda Accord SE Coupe (Lola)

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                    #10
                    Yes, the black box is forward/slightly above the CC module. 8 pin connector. Sorry, don't have an electronic copy of the wiring diagram from the manual.
                    90 LX 4dr 5 spd 396,014 (sold 1/1/2022) - MRT: http://www.cb7tuner.com/vbb/showthread.php?t=201450
                    08 Element LX FWD AT 229,000 - MRT: fleetw00d : 2008 Honda Element LX - CB7Tuner Forums

                    Comment


                      #11
                      Hopefully this is the diagram for our cars cooling circuits.

                      As a side note, I'm not the best at reading these.



                      Here is what I have done to test the cooling and a/c condenser fan.

                      AC Condenser Fan - jumped the following wires together
                      Blk/Ylw -> Wht
                      Ylw/Blk -> Ylw/Wht

                      Cooling Fan - jumped the following wires together
                      Blk/Ylw -> Wht
                      Ylw/Blk -> Ylw

                      Doing the above 2 combinations, I think should have kicked each of the fans on separately when the ignition switch is in the II position.

                      The result of this testing, still hasn't proved successful as neither of the fans will kick on yet.

                      I may have totally jumped the wires incorrectly.

                      Further guidance please.
                      MRT: 1993 Honda Accord SE Coupe (Lola)

                      Comment


                        #12
                        I've tested a few more things, and still have no cooling fans what so ever.

                        At the fan timer switch plug, both the Blk/Ylw and the Ylw/Blk both get power with the ignition on 11.98v.

                        I also pulled the fan timer switch from new Lola which is known to be working, no change.

                        Also I tested the voltage at the fan plug to see if anything was coming through with the ignition on and the fan switch plug jumped, result 0v.

                        Really hoping someone can point me at something else to start testing. Sonik?

                        Not sure if this is related or not as well but I don't have headlights either. I have marking lights, but no headlights.
                        Last edited by Rilas; 04-13-2018, 09:27 AM.
                        MRT: 1993 Honda Accord SE Coupe (Lola)

                        Comment


                          #13
                          Rilas, I had a chance to look through this thread and I have come up with a few more tests for you to run.

                          Checking the relay inputs:
                          The key is off during these test. You will be removing the relays and probing in the socket. You should see readings similar to this. I am not sure which pins are which, but you can try all 4 and note what you come up with.

                          https://flic.kr/p/23ppwq5

                          Next, you will short the cooling fan switch BLU wire to ground. Using the remaining socket pins test for continuity to ground. It should be a direct short with the resistance being less than 2 ohms.

                          https://flic.kr/p/23ppwmN

                          Finally, you will apply 12v to the last remaining socket pin AND the switch BLU wire still shorted to ground. You will have to reinstall the relay for this and the fan should kick on after performing this test if the other tests were good. A simple way to do this is to simply jump the WHT wire from the fan timer to the YEL/WHT and YEL wires, individually of course. You should be able to hear each fan turn on.

                          https://flic.kr/p/266rpDS

                          I uploaded this from my phone, so the pics may not show until I get to my PC.
                          Last edited by sonikaccord; 04-14-2018, 02:56 PM.

                          YouTube Clicky!!

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                            #14
                            Sonik,

                            I was able to partially test last night but not finish testing.

                            So the cooling fan relay sockets in the fuse box do show 12v on a socket with the ignition off. The condenser fan relay doesn't have any power until the key is on, I did not test it in position I only position II.

                            Secondly, grounding the blue wire tested back with 1.8 ohm's of continuity to ground. I did not test this on the condenser fan relay socket.

                            I did ground and add 12v to the blue wire in the cooling fan relay plug in the fuse box. I was too tired to pull the cruise control unit out and test the fan timer switch plug. I will update with the results of that tonight.
                            MRT: 1993 Honda Accord SE Coupe (Lola)

                            Comment


                              #15
                              Alright so I was able to complete testing a few minutes ago.

                              With everything jumped as described above when inserting the relay the cooling fan will kick on. When jumping the fan timer plug in both of these orientations WHT -> YEL/WHT and WHT -> YEL both turn on the cooling fan, not the condenser fan. I'm totally fine with that, as at least a fan is kicking on.

                              Where am I headed from here?

                              Also thanks, for the advice Sonik!
                              MRT: 1993 Honda Accord SE Coupe (Lola)

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