View Full Version : Electric Fan WOWS

05-16-2004, 11:06 AM
Back years ago my fan quit working properly so i hard wired it with a 20 amp relay and KO power source and a manual switch. Well that seemed to work out pretty well for a few years. Then the relay burned up/quit and i decieded to replace it with heavy duty starter relay... the first one lasted 6months the second one burned up in a week. Any Ideas on getting this thig temporaly fixed fix today with out buy another $22 starer relay. Long term like next week i'd like to have the fan running off the computer like it's suppose to. Where do i start? also would like to get back to the stock temp thremostat as well. i beleave this take a active role in cold/warm rich condition and will help clear this stuff up. right now running temp is just below the "n" NORM. But on the highway at 70-80mph the temp climbs to about normal maybe a little higher. i beleave stock it ran between the "O" and "R". Doesn't the sc need to be at the right temp the get its fuel curves correct.

XR7 Dave
05-16-2004, 11:35 AM
It could be part of your problem. The fan is not supposed to run going down the highway. Make sure that your air deflectors are all intact and your bumper cover is not hanging down. If air is not being properly directed into your radiator, it will bypass it causing the car to run hot.

You could simply be experiencing a gradual calcifying of your radiator as well.

As for the wiring part of it, you have a fusible link at the solenoid that may need replacing. If you replace that, then all you have to do is reconnect the factory wires and thermostat and you are good to go. The stock fan will come on at 210 degrees which is correct for a 195 deg thermostat. The stock EEC program will enter proper run tables after 180 degrees. A 180 degree thermostat with the proper fan controller will keep the motor running at 190-195 degrees also but it reguires that you set it up correctly. Running the fan whenever the key is on is a good recipe for problems.

You may also have the fan wired for high speed operation. Because the fan is a two speed motor, you MUST engage the low speed fan first, and then the high speed must be engaged only after the low speed fan has been operating first. The logic and/or relays to accomplish this is somewhat complex so the stock setup may be your best bet.

I run my cars with 180 degree thermostats and the stock fan settings with no problems. To me that seems like a good alternative that is reliable and effective.

05-16-2004, 01:47 PM
i think i have a 180 in there now.
where's this fusable link located/run? i still have the factory wiring in place i just spliced into it by the connector. What temp/postion on the factory guage should the fan come on or should i see a the voltage increase at?

i think the heat build up on the highway may be cause by the 3:73's 70-80 mph its running like 3000+.

05-16-2004, 04:54 PM
ok put the code scanner on and my fan turned on during the pretest mode. it started raining again so i didn't get the codes but i think the only one was for the tps code 53. what should i check next on the fan issue?

Duffy Floyd
05-16-2004, 05:03 PM
The fusible link is located on the driver's side fenderwheel just to the rear of the starter relay and in front of the washer reservior. What year SC do you have so I can send you the wire color codes? On mine (a 92) the wire running to the fan circuit starts out as a yellow wire from the link. There are actually two fuseible links right next to each other. The one for the fan is a 16 AWG Fusible link.

05-16-2004, 06:18 PM
see it in the member section under john dean 92 sc

XR7 Dave
05-16-2004, 06:33 PM
If the fan is coming on during the EEC test, then it is working. I would look elsewhere for your problems. Yes, 3.73's will create some heat on the highway.

05-17-2004, 08:04 AM
Where else should i look the temp sensors? i know for sure the fan doesn't come on when the car is running no matter how hot it gets, i turned the switch off in the glove box one time and forgot about it, went in the store and about later 10 minutes kabooom-there was radiator all over the parking lot..

XR7 Dave
05-17-2004, 11:24 AM
The fan is controlled entirely by the EEC. If it came on during the self check, then the circuit works and is good. There are two signals which tell the EEC to turn on the fan. 1) if your AC is charged, then when the compressor kicks in the fan will come on. 2) when engine temps exceed 210 degrees. If you know that your engine has exceeded 210 degrees and the fan has not come on then your ECT sensor may be faulty. The ECT is located in the adapter where the heater hose goes into the intake manifold. If you have installed any auxillary wiring or switches, then all bets are off. ;)

05-17-2004, 12:28 PM
1. no ac charge.
2. I want to say i read that if you were to unplug the temp sensor the fan will run with the key on, thus telling you that the sensor is probably bad. Is this correct?

Now if all it takes to get this fan running right is a freaking temp sensor i'll...... :D

05-17-2004, 07:43 PM
Well i unplugged the sensor with the car running and the fan can on. so i drove down to auto zone with it unplugged and the check engine light was on. It ran cleaner than normal, but lacked power. I installed the new sensor and that fixed the fan situation and seemed to cleaned up a lot of other drive ablity issues (i thought the TPS was going bad, in another post). i had to set the idle both hard stop and IAC screw to get it to idle right. The rpm's dropped from 1000rpm to about 800rpm and would die with the wheel turned and what not, so i adjusted it accordingly. Now it seems that its not advancing the timing or something so i tried resting the computer (may not have let it sit long enough for it rest). Like 3000+ in 3rd it didn't want to go. I hope this is just the computer tripping cause i pulled the sensor and the check engine came on. The light went off as soon as plugged in the new sensor.

Driving in town it seemed to run "normal" heat would to the "M" and the fan turns on and cools it to the "O".
Driving on the highway maybe different cause the speedo's off so bad and the fan may not run enough, but i find out soon.

Thanks for the help getting to fan running right....

Kinda Seems like this post....crap... but i have the battery disconnected again.


just got back from resetting and driving.. still doesn't pull on the top end any more. i put the superchip in it and it runs better but still somethings wrong. may have something to do with my other post about the ground wire..

05-19-2004, 11:57 AM

still running under powered. i put the superchip back in it and it picked up a little. what do i do next? it went from hard starting, running rough, rich, powerful, and to much timing for the chip to squat...

David Neibert
05-19-2004, 12:11 PM
Test the TPS voltage.


05-22-2004, 04:52 AM
Get rid of the superchip!..Sounds like your computer was getting faulty information.

1. Clean the mass air! My friends tbird power faded away till it was totally gutless, cleaning the mass air brought some of the power back but in the end it was too far gone so he had to get a new one. The new mass air restored all the power.
2. Test the tps voltage, green wire(I spliced another wire into the green one for voltage checks with the unit installed) idle should be .92 perfect( .98 for mustangs.. I noticed that the sc voltage will creep up a little as the unit gets hot.) As you goto full throttle voltage should climb to about 4.5-4.8? at wot. just turn the ignition to hot for readings. Look for spikes in voltage s you goto wot.
3. Replace both water temps one behind the a/c is for the computer and the one in the water neck is for the gauge.
4. you can buy a mechanical trio guage set at wally world for 20 bucks! I love mine! Screw the o r n z x readings .. give me numbers!
5. replace air temp which is located on manifold inlet.
6. replace plugs, sounds like the old temp sensor was bad so the car may have been running rich, plugs could be fouled out.

Start with the tps its the cheapest fix .. Good Luck

05-22-2004, 01:36 PM
Changed the TPS yesterday and fixed the crank sensor shield ground. reset the computer and still runs like a dog. i guess i'll look at cleaning the MAS and the k&n today. I don't think i have changing the plugs in me this weekend.