radiator fans
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radiator fans
how to check/jump the radiator fans to come on, my coolant gauge isnt working, buzzer light was on, but got it fix because i forgot to connect the black wire near the a/c compressor, but the guage still doesnt move up at warm up even at 105c and my fans dont kick on. My reading on the PFC is working
its in the diagnosis black box under the hood. Just jump the relays in there. should be a GRN you tap into the radiator fans cant remember which one but that will run them for you. put the key in the ignition and turn it to on...
This thread will show you how to check the function of each relay, including wire colors:
https://www.rx7club.com/3rd-generation-specific-1993-2002-16/2-trigger-cooling-fans-462760/
There's a simpler way to just turn the fans on (connecting a wire to a couple of pins in the diagnostics box), but if you suspect a wiring issue, it's not a bad idea to just check all four relays. You can slide an extra wire in from the rear of the connectors once you unbolt the bracket that holds the relays on.
-s-
https://www.rx7club.com/3rd-generation-specific-1993-2002-16/2-trigger-cooling-fans-462760/
There's a simpler way to just turn the fans on (connecting a wire to a couple of pins in the diagnostics box), but if you suspect a wiring issue, it's not a bad idea to just check all four relays. You can slide an extra wire in from the rear of the connectors once you unbolt the bracket that holds the relays on.
-s-
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From: Metairie, LA near new orleans
what temp were your fans set to in th PFC? IF you just want to test to see if the fans work then use the diagnostic box and jump the TFA to GND. IF you want them to come on at a lower temp then u need an interface (Datalogit ) to turn fan temps down.
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i jumped the tfa and ground and they still dont come on. the car warmed up to 111c and they still didnt turn on. my temp guage still doesnt work and now the buzzer came back on. im using the funnel to take out the air pockets but i see no more air bubles coming out. and its not taking anymore coolant, got new thermostat, new water pump and a freshly built motor with 0 miles on it. any clues?
Last edited by T88Rx7; Nov 4, 2006 at 05:31 PM.
to force the fans on, turn on the AC. if that doesn't kick the fans in, you either have an electrical issue or the rans are dead.
How do you know it was at 111c if your temp guage is broken?
How do you know it was at 111c if your temp guage is broken?
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From: Florida
Originally Posted by 93VRTouring
How do you know it was at 111c if your temp guage is broken?
PFC shows 111c, my stock guage doesnt move a bit. I dont have A/c in the car. no condensor or anything. would pushing the a/c botton on still activate them?
This is a great way to figure out why your fans aren't coming on.
From this thread. The thread has the diagrams which will make it pretty clear.
Good luck!
1wide7,
I have attached a copy of page Z-116 of my 1994 RX-7 Workshop Manual. It is both an illustration of, and a guide to, the Data Link Connector under the hood. The terminal locations are shown in the lower portion of the page, and their functions in the upper portion.
You will note a "TFA" terminal in the bottom row, just to the right of a "GND" (ground) terminal. If your car has had the fuel system recall, and you jumper the TFA terminal to that GND terminal, both your fans should run. If your car has NOT had the recall performed, you need to turn the ignition switch to the ON position and then jumper TFA to GND. If that procedure runs your fans, then you have proved that Coolant Fan Relays Nos. 2 and 4, the fan motors, and the 60A cooling fan fuse are all good.
The above test has NOT proved that either Cooling Fan Relay No. 3, or the Water Thermoswitch, is OK. The Water Thermoswitch activates Relay No. 3. That happens when coolant temperature is between 101°C (214°F) and 108°C (236°F). You can test the Coolant Relay No. 3 by disconnecting the electrical connector to the Water Thermoswitch and touching the cable harness connector terminal to a chassis ground point. If the fans run, the Relay No. 3 is good. If not, there is a wiring problem between the connector and the Relay No.3, or the relay itself is bad. If the fans run for this test and all the other tests, but do not run when the engine is hot, the Water Thermoswitch is bad.
I have also attached a copy of page Z-40, which is the wiring diagram of the coolant fan system, FYI.
I have attached a copy of page Z-116 of my 1994 RX-7 Workshop Manual. It is both an illustration of, and a guide to, the Data Link Connector under the hood. The terminal locations are shown in the lower portion of the page, and their functions in the upper portion.
You will note a "TFA" terminal in the bottom row, just to the right of a "GND" (ground) terminal. If your car has had the fuel system recall, and you jumper the TFA terminal to that GND terminal, both your fans should run. If your car has NOT had the recall performed, you need to turn the ignition switch to the ON position and then jumper TFA to GND. If that procedure runs your fans, then you have proved that Coolant Fan Relays Nos. 2 and 4, the fan motors, and the 60A cooling fan fuse are all good.
The above test has NOT proved that either Cooling Fan Relay No. 3, or the Water Thermoswitch, is OK. The Water Thermoswitch activates Relay No. 3. That happens when coolant temperature is between 101°C (214°F) and 108°C (236°F). You can test the Coolant Relay No. 3 by disconnecting the electrical connector to the Water Thermoswitch and touching the cable harness connector terminal to a chassis ground point. If the fans run, the Relay No. 3 is good. If not, there is a wiring problem between the connector and the Relay No.3, or the relay itself is bad. If the fans run for this test and all the other tests, but do not run when the engine is hot, the Water Thermoswitch is bad.
I have also attached a copy of page Z-40, which is the wiring diagram of the coolant fan system, FYI.
Good luck!
