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Been a reaaaaallllly long time since I've posted anywhere on here - could use some help. After being sidelined w/a broken shoulder for about 6 weeks, got the camaro out today. Noticed in traffic it was running hot. Way too hot - like 250. Got it to where I was going and back. I noticed the fan wasn't kicking on.
I unhooked only the clamps on the loom from the fan down the passenger side to try and get slack to put a direct drive starter in it. Long story short was too short on cable, didn't feel like messing with it, so I screwed the clamps down. That's it.
I did notice after tracing the loom - the connector in the attached picture was disconnected. I don't recall disconnecting it ...ever. Any idea what it goes to? And any idea where to start trouble shooting why the fan won't turn on? Gauge seems fine - I watched it start cold and heat up. And get hot, then the t-stat open and drop. Long as I kept moving and kept air running into it, the car was happy. Stop and go - screwed. Open the hood hot, fan is sitting there. Spun it w/a stick - it's not seized.
I should have also mentioned my arm is still pretty messed up so anything I can do or chrck on the top end would be preferred. getting the car on jack stands at the moment would be a helluva challenge, if not impossible. I could enlist help...but topside first if there's anything would be easier.
read a couple other threads. dunno if it helps but the ac hasn't worked since I bought the car..compressor was leaky and dead. turned the ac on, and the fan still did not spin. Idk if the dead compressor would affect that at all tho
Don't suppose you have a picture handy of what I'm looking for? And by check - make sure connected or is there another way to test them with a meter? I have a meter - just not sure what setting to put it on. Also any idea what that random wire is?
Anyone? there was a 20a fuse holder by the battery. fuse was good. didn't see a relay. managed to get the car in the air which wasn't easy...both sensors on the passenger side were plugged in. didn't look like any wires were broke.
Is the relay the one on the driverside firewall - 4 wire? I searched - TGO claims it is, but when I look up the part at any auto parts store it's a 5 pin. Are there more than 1 fan relay in the car?
You can also pull the fan switch wire and ground it to check if the fan turns on. If it does then your fan switch is bad. If it doesn't then your relay or fan motor needs to be replaced.
So i dug further. The relay had 2 crispy pins. Harness at the top had the plastic looking melty, but the pins themselves looked ok so I put in the new relay. I did the following, in this order:
Turned on the AC. Fan worked - so that seems ok.
Turned off the AC. Fan turned off.
Ran up the engine temp again to redline, fan never came on.
Turned on the AC - fan never came on.
Relay was pretty warm to the touch, but nothing looked burned...but I'm thinking I nuked the new relay..again.
Picture of the connector is attached. What would cause me to rip through relays like they're going outta style?
Assumption is you have a single fan here. Your fan is controlled by either the AC or the temp switch. The fast way to make sure the relay is working is to turn on the AC. The fan should turn on. If for some reason it does not, the next thing would be to do as tealman said and pull the wire off of the temp sensor. this will be between 7 and 8 cylinder in the head. Just pull the connector off and ground it to the block or something equivalent. It should turn on there for sure so long as the relay is good and the relay has power. If it does turn on for either of those tests you may have a faulty temp switch. If it still does not then we need to check the power, this is a red wire on the relay. It will be hot at all times so check it key on or off should be no difference and should have battery voltage around 12v. If not then you have a fusible link that has farted out. If you do have 12v then the next will be relay coil voltage which is switched 12v. Check it with key on and you should see 12v. Note: both of these will be checked 12v to chassis or battery ground. If no voltage check your fan fuse under the dash, it is 20A. If we get this far and everything checks out then we should ground the green/white wire right by the relay. You can do this by making a back probe to get into the back of the connector with the relay still plugged in. You should hear a click if the relay is functioning. One other thing to check when doing these tests is the red/black wire from the relay to the fan. When you are testing and the fan is not on you can double check the voltage at the fan connector or right at the relay. Obviously if you see 12v at the fan connector you either have a bad ground or a bad fan. If still no dice then the relay is suspect.
Just saw your post when I posted, crispy connections can have high resistance which results in heat. Heat is the arch enemy of electronics. The connection between the relay pins and the relay should be snug if its loose it may be time to replace the connector. I would ground that temp switch wire to prove the wiring on that and if it runs replace the switch. Sounds to me like the wiring is ok though.
Correct - single fan. Sorry shoulda mentioned that.
So when I turned on the AC it did turn on. Initially. it did turn on. After I ran the car up to about 250 and the fan didn't come on - i turned on the AC and it wouldn't come on again. At 15 bucks a pop for relays....I can't keep just swappin em out to test.
The relay tests - power, and coil voltage would be at the connector correct?
So - given what you see, your next step would be to ground out the switch and go from there? And stupid question on the switch ..I replaced it once a looonnngg time ago. If / when I pull it - does it **** coolant everywhere? Trying to recall so i put a catch under it if it does and can't remember.
Also, there are no stupid questions! Further, the fact that the AC turns it on makes the temp switch suspect number one. I'd have to look up the actual temp it should turn on but my initial thoughts is lower than 250 anyway. I would give that connector some love, clean the contacts with electrical cleaner and see if you can get in there to bend them a bit so they mate tighter with the relay contacts. Then give them a squirt of dielectric grease for protection. It looks like they are getting hot. That may be the only problem too, should take care of that first.
Hey guys, I am having similar issues with my single fan not turning on. I bought a new fan switch from Napa (FS111) that is supposed to turn on at 220 and turn off at 204. However, when I installed it and tested it did not turn on the fan at all. I bought a new pigtail connector and tried grounding it, and that does turn on the fan, so I know that the fan and the relay both work. I then removed the new switch, returned and bought another new one, so I know the switch is not defective. The switch is screwed in all the way and has no teflon tape, and I tested it with a multimeter to ensure that the shell of the switch is able to be grounded by the metal of the head.
Any thoughts on why my fan does not turn on at any temperature? I am running out of ideas. Thanks!
The aftermarket switches are known for having varied activation temp and deadband precision. How hot did it get before you aborted the experiment? I think every switch I’ve used has been off 10-15 degrees from what was expected and always higher than expected.
what do you think would cause the relay/pigtail to burn up like that?
Very simple. Too much current, too little metal.
IOW, cheeeeepeness and under-engineering.
If I were faced with that situation I'd buy a whole relay/connector combo and change it all out. I'd solder the new terminals to the original wires, NOT rely on the crimp connection alone.
The aftermarket switches are known for having varied activation temp and deadband precision. How hot did it get before you aborted the experiment? I think every switch I’ve used has been off 10-15 degrees from what was expected and always higher than expected.
I waited until about almost 260 degrees to abort the experiment and I used an infrared thermometer to measure the temp at the thermostat housing. The switch should have turned on at 220 degrees so I am not sure why its not working properly.
r Martin - mind starting a new thread to avoid confusion on which reply addresses which problem?
I decided to test the relay today in the car...noticed it was loose. Im hoping a new pigtail and relay will fix the issue. I think enough plastic melted thst it's loose.
that link for 20 bux...it's the right relay/ wires? they color coded too?
A relay is a relay is a relay is a relay, as far as being "right"... it's just an electrically operated switch. A small signal (temp switch) controls a magnet (relay coil) that moves an iron piece that has the high-current contacts on it, and makes or breaks or changes over or lifts off, to switch the load (fan motor) on or off. It's a "make" configuration in this case. Gotta be the simplest thing imaginable.
If it has the right coli voltage (check), adequate current rating for the load (check), correct contact configuration (form A - check), kinda hard to go wrong. From there, it's things like, waterproof (check), physical fit (check), price.
No colors involved. You put the big fat connector pins on the big fat wires and the little skinny ones on the little skinny wires. Put them in the holes of the connector body that mate with the pins of the relay that are either the load contacts (big fat wires) or the coil wires (little ones). It's even simpler and eeeeeeezier than colors. Big fat, little skinny. A color-blind person can handle it.
That connector in #9 is probably toast & not dependable. Indicates that there was WAY to much current draw, for too long. Sofa has everything correct, re: the repair kit. However, I would add, that before assembling everything, try the following. The 'big fat wires' should be as follows.
1): The high current supply is probably constant. For sanity, make sure its providing 12v. It may have a fusable link somewhere in the circuit closer to the battery. Should be constant power, but may need to check w/ ignition on. If there is no power ever, get a length of 10 gauge wire, to go directly from the battery, for step 2 below.
2): When power at this wire is certain, check the fan by making contact w/ the other 'big fat wire', the actual fan connection. Just because the fan motor turns by hand, it could still be drawing way to much current. Let run for awhile. Under normal conditions that manual connection should get pretty warm to the touch. But if its smoking hot enough to melt the connector plastic, the wire insulation near the connection will be getting very soft. In this case, the fan motor is probably bad.
If the power side of the relay circuit is good, then the problem may lie in the switching side. One of the smaller wires connects to the temp. switch, and provides the ground side of the control circuit. The other small wire provides the 12v, & should be switched ignition, i.e. when ign. on -- easy enough to verify.
Didn't read paulyc close enough the first time, which is spot on. Hopefully, my explanation may fill in some blanks.
However, if memory serves me right, the sensor in the bottom of the block, is for the dash gauge. The fan sensor switch is somewhere up top, in the intake manifold or thermostat housing. This one is a simple on-off output, where the block one is a variable resistance output, that the dash gauge calibrates to an actual temp. value.
Hope this helps, let us know how it turns out.
Last edited by l_dis_travlr; 07-25-2018 at 02:05 PM.
with the dislocated shoulder a week into activity after 2 months...I managed to swap the connector. soldered everything but power which I had to crimp connect due to lack of any control of my arm by that point.
turned the car on, fan came right on when accessory was on. then when I started it stayed on. that ain't normal is it?
Only if the AC is on when you turn the key. Otherwise you are getting a ground somewhere else. If the AC is on turn it off and it should stay off until the temp switch grounds. If it still stays on, disconnect the temp switch and see if it turns off. I’m guessing you have the AC on though and that is a normal operation.
ac started on, but I turned it off and the fan kept going. with my messed up shoulder and lack of mobility I'm almost to the point of saying the hell with it and just taking it somewhere. it's frustrating knowing what to do with your guys help and not being able to, or being in pain doing so. pulling the wire off the sensor under the block...any tricks or just grab and pull? having to do it lefty I can't see what the hell I'm doing. it's all just feel.
Cool thx. I'll play with it a bit more i guess on my own if I can. anything with the sensor leaves my face under the exhaust or wheel lefty. cant early see a ton. I'd rather do it myself...just getting frustrated. 2 months ago it'd have been a different story and done by now.
just to double chec, turned the car on...fan came on with ac off. got under it...and after some choice words got the wire off the fan switch. got up started car and the fan did not come on. bad switch then?
assuming fan constantly running and me not knowing led to the death of the relay and.pigtail?
Last edited by KCobain147; 07-26-2018 at 05:38 PM.
So as noted in the last post - when I started today the fan came on with the AC off. Pulled the wire on the fan switch, turn the car on again, fan was off. Figured it was the fan switch. Replaced the fan switch, took a bath in coolant, connected the wire,then topped off my reservoir. Turn on car, fan is off. Turn on AC, fan comes on. So far so good. Let the car get warm - got hot stupid fast. Fan never came on. Checked the upper radiator hose because of how quick it got hot - it was cold to the touch almost as if the thermostat never opened. Only had this happen tho after replacing the fan switch.
What am i missing?
Just realized i forgot to top off the radiator....perhaps the issue?
Last edited by KCobain147; 08-06-2018 at 04:50 PM.
How hot is hot? If it is overheating hot then there is a good chance you could have a sticky tstat, make sure you are coolant full though too. Low coolant can give you problems especially if you aren’t driving around getting the rpms up.
Coolant was definitely non existent in the rad. Filled it. Top hose got hot. Fan never came on.
So- before i swapped the switch, but after I replaced the relay/pigtail, the fan came on when the car came on. Disconnect the switch wire - fan didn't come on. I'd have to think my crappy wiring job on the relay is fine, and wiring is fine since the fan came on at startup. Odds are switch was grounding. Replaced switch, connect wire, Fill with coolant. Fan won't come on.
Is it possible the switch isn't tight enough? Should the threads be enough or do I need the nut part on the backend seated against the block? I didn't wanna over tighten..but I probably coulda spun it more.
no sealant whatsoever. no tape, no liquid, nothing. dug through some old threads and got scared of it. should it be wrenched down till it don't turn (will that happen being brass?)
You should be ok there then as long as you’re not leaking. The only other things would be to make sure the connector is seated all the way and verify the temp the new switch is supposed to activate. Also, if you are using the dash temp gauge to determine the temp, you should make sure that is correct as well with a separate test gauge.
Always possible to overtighten but I wouldn’t be terribly concerned with it if it isn’t leaking it should be more than enough to function normally. The switch body just needs to be able to ground to the block. While you are looking at it you can do a simple test to double check the switch wiring is working by jumping the wire to the block. You could even touch it to the switch body and make sure the body is making a good connection to ground as well. Both ways the fan should turn on with key on.
So it's fixed, just not the way I'd prefer. Turns out the old switch popped on around 230. New one isn't till like 250 ish- the edge of the redline which I don't care for. Would not have even noticed because I dont like the car getting that hot, but was bullshittin with a friend that came to help and accidentally let it get a bit hotter than preferred. Any idea where to pick up one that'd kick on lower?
The tl;dr version of this thread for my self and anyone else that may need it:
Car was over heating - fan wasn't coming on.
Got car home. Tried to turn on air conditioning. Fan didn't come on. Pointed to the relay.
Pulled the relay. Relay was burned. Pigtail/connector were burned up. Replaced both.
Turned on car. Fan came on immediately while cool, pointed to the fan switch stuck keeping it on.
Disconnected fan switch wire. Fan stopped.
Replaced fan switch. Reconnected wire. Fan didn't turn on when expected.
Pulled fan switch wire, grounded, confirmed all wiring worked. Let the car heat up even more. Fan turned on. All is well. Kinda.
So it's fixed, just not the way I'd prefer. Turns out the old switch popped on around 230. New one isn't till like 250 ish- the edge of the redline which I don't care for. Would not have even noticed because I dont like the car getting that hot, but was bullshittin with a friend that came to help and accidentally let it get a bit hotter than preferred. Any idea where to pick up one that'd kick on lower?
The tl;dr version of this thread for my self and anyone else that may need it:
Car was over heating - fan wasn't coming on.
Got car home. Tried to turn on air conditioning. Fan didn't come on. Pointed to the relay.
Pulled the relay. Relay was burned. Pigtail/connector were burned up. Replaced both.
Turned on car. Fan came on immediately while cool, pointed to the fan switch stuck keeping it on.
Disconnected fan switch wire. Fan stopped.
Replaced fan switch. Reconnected wire. Fan didn't turn on when expected.
Pulled fan switch wire, grounded, confirmed all wiring worked. Let the car heat up even more. Fan turned on. All is well. Kinda.
wtf seriously?
dude. I'm hella new at TPI but I can sympathize with your plight. OBVIOUSLY that's HOW I ended up HERE.
From what I gather the fans are two speed. (At least one of them is?) AND the computer controls the hi-speed function which is turned on @246°.
Are you certain what you're saying is actually what or HOW it is happening?
Maybe look again.
I bought a $12 fan switch on ebay that is ON at 200° and OFF at 185°, coupled with a 180° thermostat.
It MAY run TOO COOL. It's too soon to tell but I believe the 246° setting is the ONLY thing that saved my engine while I was fixing the car and figuring it out?
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the fan switch is on the passenger side and the gage switch is on the driver side.
Hope this helps! ����
i think my running hot problem more involved the thermostat than the fan switch...be prepared.
Last edited by 88IROC-USA; 09-07-2018 at 10:03 PM.
So - to bring this post back from the dead. Looking to get the car out for the year. Hated how hot it ran last year w/whatever sensor I put in it. I swapped it out with a Delco D1852B per PaulyC's advice. Expect to see it kick the fan on at 220. It ran up to the deep end of the red..probably 250 or 255 before the fan turned on, then it ran till it dropped to about 220 and turned off. Should I just accept this? The one that **** the bed kicked on at 220..not off. Getting tired of taking a bath in coolant tho and would like to drive the car. Advice is appreciated.
Did you ever check the accuracy of the dash gauge temp with a test gauge? I’ve got the same sensor in a car right now and see similar behavior form it, it’s higher than advertised for sure. Mine isn’t quite in the red but it’s higher than 220. I’ve looked around for better options and haven’t had much luck. Everything works correct except the temp is high then?
Did you ever check the accuracy of the dash gauge temp with a test gauge? I’ve got the same sensor in a car right now and see similar behavior form it, it’s higher than advertised for sure. Mine isn’t quite in the red but it’s higher than 220. I’ve looked around for better options and haven’t had much luck. Everything works correct except the temp is high then?
I agree with pauly....when i built my 350TPI i put a new coolant temp sensor in, and had to guess at what part number i'd need since the auto parts store listed like 3 different types for my exact trim and options. Now my fans come on at about 240-250 according to the gauge, but it actually runs cooler. I do remember reading that you're using an infrared thermometer though. heres a thought though too: are you still having issues with it coming on when you turn on the a/c? If that were the case then imo you'd still be having issues with the relay. It is possible that somewhere is running too much power and burning the relays up.
Did you ever check the accuracy of the dash gauge temp with a test gauge? I’ve got the same sensor in a car right now and see similar behavior form it, it’s higher than advertised for sure. Mine isn’t quite in the red but it’s higher than 220. I’ve looked around for better options and haven’t had much luck. Everything works correct except the temp is high then?
No I didn't...unfortunately don't have one. I do have a set of overlays on it as well, but I feel like they were pretty equal to the stock ones under it. In lieu of trying to find/buy a test gauge..just roll with it then ya think? It seems as though it's working as it should, just not turning on when I'd prefer.
07-19-2018, 07:09 PM
