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1994 Toyota Camry Fan Relay Question

My 1994 Toyota Camry has 3 Fan relays, and one Magnet Clutch Relay (for the air conditioner)

I had an automotive repair shop do some work because I’m having problems getting my fans to turn on properly. After i got the car home, it’s still overheating and I’m still having fan problems, so I looked in the fuse box and discovered that the mechanic had removed one of the fan relays and used a jumper as a temporary fix. Also, my other 2 fan relays/and magnet clutch relay have all been removed and replaced in different locations in the fuse box. Now I don’t know which relays are the proper ones for the proper location.
If anyone has a 1994 toyota camry, 4 cyl (or similar Toyota with the 5S-FE engine) can you please verify the numbers on these relays? I’ve spend the better part of 10 hours researching this and am at a loss.

These are my relay numbers:
Fan No. 1 Relay # Green 90987-03003 156700 0130
Fan No. 2 Relay # no relay, but has a jumper :frowning:
Fan No. 3 Relay # Black 90987-02010 156700 0060
A/C MGN Relay # Black 90987-02010 156700 0060

Also, since I don’t have a Fan No. 2 relay, does anybody know the number of that relay that is supposed to fit there, so that know what to search for online I cannot locate it in the Toyota Camry repair manual?

Thank you!!!

Is there any way you can go to the dealer’s parts department and get the part number? That would be easier and more accurate and you can confirm the ones you already have.

I bet all three fan relays are the same. They usually are.
Since this mechanic clearly McGyvered your car, he may have mixed them all up and put one in the AC relay socket.

Why are you still overheating? Are the fans on or off?

Here’s a schematic to your fan situation. I guess they aren’t quite identical…
It is a bit of a wonky situation, with the AC pressure switch and water temperature switching needing to be on for the fan to turn on. Seems to me that this means that when the AC pressure switch goes off, the water temperature switch will lose control over that relay. It is almost like they should be parallel, not series…

Anyway, the AC fan is off, then? When you say your fans aren’t working, what are they not doing?
Are they working with the AC on but not when it overheats?

Thanks for all the replies…
Well, my fans are working every time I check them, however, when driving in stop-n-go or in mall parking lots for instance (not going over 10 MPH) then the engine starts slowly overheating, and the air conditioner starts blowing out hot/humid air.
However, every time i’m driving above 45 or 50, then the engine cools down and the AC starts blowing out ice cold air again. It seems to be clearly a fan not coming on issue, however, my mechanic says the fans work, and every time i pop the hood, the fans are on.

Since your McGuyver mechanic did some unconventional stuff, could it be that the fans are turning the wrong way?
If the fans are turning the right way and at the right time, it could be that your radiator is at fault. It may be blocked.

RemcoW,

Just checked my fan direction, one turns clockwise and the other turns counterclockwise. (They’re the exact same fans, by the way). Since one is pulling air thru the radiator and the other is pushing air thru, it seems like I need to somehow reverse the fan to get them both running in the same direction to not counteract one another.
question: Any idea how to get both fans running in the same direction?

Also, I tested the fans directly by connecting them directly to the battery (just to test the motor and speed), and they ran at a high speed, much higher than they run under normal operation.

question: do the fans operate at a slower speed normally, and then increase speed as the coolant temperature increases? It seems to me they should operate at the same speed no matter what.

I posted a reply in your other thread about this, but this question is much more elaborate.

When you hooked the fan directly to the battery, did you cut wires? I’ll bet you crossed the wires and reversed the polarity of the motor to get it running in reverse.

No they run opposite direction in normal configuration ( when plugged into the harness). The fan was replaced several years ago… Maybe The mechanic hooked it up backwards. Also it has not been cut.

He must have hooked it up backwards or maybe that fan can be mounted backwards.
We may have very well stumbled onto your problem.
When you’re sitting still it blows hot air into the radiator and condenser so there’s no real exchange.
It isn’t a room fan that has an ‘exchange’ mode where it refreshes the air by it coming in through one fan and going out through the other. You want them to blow the same way.

Does the connector go in either way?

Another weird thing is that they run slower when running in the harness than if you hooked them up directly. Can you measure the voltage across them? It must be significantly less than 12V. Maybe there’s some resistance in the line that isn’t supposed to be there. I’d check that ground point on the right of the schematic. Clean it off and maybe bridge it with a booster cable: negative lead on negative battery post, other negative side on that ground point. Don’t use the red part of the booster cable - you’re just enhancing the ground connection temporarily to see if it makes a difference.

It could be that the fan was wired wrong from the manufacturer, and has been running backwards all this time. Hard to tell.

nah, the fan broke several years ago and was replaced with a different fan. That’s how I know it wasn’t that way from the manufacturer. I’m guessing it would have to have been installed backwards. My next step i guess would be to check the connection that goes from the fan into the harness to see if it can simply be reversed, thus changing the direction of the fan. if that’s not the case, I guess I could remove the fan and turn the motor around and replace. Or, for a quick fix, i guess I could cut the two wires and reverse the polarity to get the fan to run the other direction.

@BustedKnuckles:
Yeah, could be. You’d imagine they know how to build replacement fans but stranger things have happened.
That would be hosed beyond all belief.

Ok i will get to work on this and get back on here in a while. Thank you BOTH for your help!!!

Ah, so it lets itself be mounted backwards, then? Well, there’s at least one of your problems.

The other problem of it spinning slowly could be just because there’s a mess of wire in between it and the battery. Clearly not a great design because a designer normally tries to minimize losses but that could be inherent of all Camries of that era.

First see if you can get it to not overheat by making the fan spin in the right direction.

@boeingav8r: let us know how you make out, even if you get it fixed.
It may actually help someone else with similar problems.

In looking at the radiator cooling fan circuit diagram, I notice that both fans will come on when the A/C compressor clutch is energized. However, the two will be connected in series so both will run at approximately half speed. If the A/C overpressure switch or the engine coolant overtemperature switch open, the three relays bring both fans up to full battery voltage and thus full speed. This will happen if the A/C compressor clutch is not energized or energized.

See if the fans are running if the A/C is off and the engine is hot enough to need the fans running. You can do this by idling the sedan while stationary and letting the coolant temperature rise.

Hope this helps.

Had to take a second look but @researcher is right. They do run in series by clicking one relay out and the other in.
What a convoluted mess.

It does mean that the speed you’re seeing when it isn’t oveheating is okay.
It does not account for it spinning the wrong way.

If the replacement motor was aftermarket, its not that uncommon for them to not come with a plug and the mechanic has to splice in the old plug. In that case, it is easy to get the wires backwards.

Well now it looks like I’ve inadvertently created a worse problem for myself. Remember how it was said earlier that a mechanic “macGeyvered” a jumper wire in the socket where the missing FAN #2 relay is supposed to be? Well, I removed the jumper so I could get a better look at the socket and determine what type of relay I needed to buy for it. Well, when I went to replace the jumper, I heard a “click” somewhere in the relay compartment and now the fans will not work AT ALL.

Again, I retested the fans by hooking them up to the battery and they both work, but still do not work when connected to their harness.

then I removed the engine temperature coolant wire and tested for continuity and it’s fine.
I replaced the 30 am RDI and CDS 30 A fuses and still nothing. I’m at a loss.

Ok, I’m back in business. In the Toyota Camry manual, it directed me to a small fuse box that is under the drivers side dash, behind a little coin holder with a door. Remove the door to access it. The ECU-IG fuse was blown. I replaced it and now the fans work again.
Now back to reversing the direction of the fan so they both pull…
Again, thank you all for your input!!