Fan not running

[gj68]

The fan in front of the radiator on my '91 Tracker is not working. It is an 8V 5 speed 4X4. The temp guage went close to the red so I popped the hood and noticed that the electric fan was not running. I have been working about 80 hours a week so I let it sit for a few weeks. I turned on the key today and the fan started running so I took it for a drive and it started heating up. I pulled over and checked the fan and it was not running. Got home and started checking things out and found that the fan will turn on if the A/C button is pushed. It will also run if you touch the blue/red wire in the condenser fan motor relay with a light tester. What turns the fan on when the A/C is not running? Why did it work for only a few minutes today? Please help.

[Ozzy77]

Well if your eng. is getting hot I think is better to find out the reason, your electrical fan in front of the car is for the a/c and sometimes is a backup for the fan clutch when the engine is too hot. You better check first the fan clutch, the thermostat (if you havent changed it for a long time get a new one), check the radiatior for leaks or clogged lines(get a liquid radiator cleanner and clean it up). Do you have any leak?, does the eng. need water if you go for a ride? Check the timing. Most of the cars runs the fornt electrical fan whenerver you turn the A/C on and the compressor is working, mine for example runs it til the engine is warm, and whenever the comp. is working. If your eng. does not get hot at idle then I will go for the fan clutch and the thermostat. Don´t take chances with the hi temp. can cause a big damage to your eng.
Check if there is nothing in the middle of the two radiators(rat nest sometimes is the reason)

[jtgh]

i presume you are talking about the A/C fan on the A/C condensor ?
this is controlled by the A/C amp logic module.

please state your question better , it is confusing, sorry.
is the engine overheating ?
if it is, did it overheat with A/C on , or A/C off,
if if overheats with A/C on, does engine stay cool if A/C is off.

here is how it works.
air-conditioner-repair

note A/C and fan are cut(killed) when ever A/C loop freon pressure drops too low. (below 30psi, and is very bad)
this action is to save the destruction of the compresser.

next, if the engine over heats, (over 235f) the A/c , again will cut , this actions to
save you from serious engine damage.

do not run A/c if car coolant temperature overheats. do not.

You need service.

[gj68]

It is the A/C fan that I am talking about. It was running hot without the A/C on. The coolant level is fine. I never have to add any. The timing is right but I have not replaced the fan clutch or the thermostat. The A/C fan used to run for a while after I parked it but it doesn't now. Yesterday it was about 95 degrees out and it came on when I turned the key on without the A/C pushed in. It stopped working while I was driving. I was at about 3000 rpm when it was getting hot and it cooled down some when I got back in town driving. Hope that is a little clearer. Sorry.

[CodyJ]

The 8valve engine has a clutch fan for cooling the engine (on when engine runs and turns on based on heat and will spin)... that fan that you say "kicks on sometimes" is the AC fan as jtgh said. You may have a broken clutch on the fan that is attached to the water pump, or your pump is bad... if you don't feel air near the engine its the water pump thats bad since you said your radiator fluid is fine!

[jtgh]

no problem, assume factory air.

the the A/C will shut down if the A/C engine over heat switch trips.
you need to fix engine first ;before workiing on A/C.

The A/C amp desides (inside)when to run fan, as does low freon switch.
the rules for the A/C fan are complex and not published (best i can tell). (hoew ever my web page shows most of them)


its a very tiny engine,if it is not running perfect the A/C is basically a torturing device.

The A/C amp many have an internal thermo sensor, I do not know this but it might.

My 91' FSM , never 1 time mentions fan tests or rules (condensor fan)
I look in my 95 fsm , same, no mention of cond. fan ops.
the trouble shooting charts ALL start with , insuffient cooling .
the fan and compresser have there own relays and there own enable lines. ( not needed if logic is not special for both)

if your fan is not comming on , when you expect it to, then check the voltage at the
4 pins of the Condensor relay to find or the reason for the fail. (any voltmeter will work)
a; loss of power to Relay. see fuse.
b: bad fan or wires to same. power out of relay ok, bad fan.
c: bad relay, no power out of relay and below are good, bad relay.
d: bad low pressure switch if you have compressor running ok it is not this.
e: loss of cab fan power. (fan blower is off) commanded off by A/C amp.
f: loss of ground at Blue/Red wire from A/c amp, do to other faults it has detected or it is bad . (acid test ,just ground this wire and test fan and relay and power) if fan activates, then the A/C has decided not to run fan. in this case you need to check all inputs to the A/C amp to lean this reason.

I am sorry I do not know all the rules of logic of the A/C amp , but I do know most of them.
The Fan is another matter up front.
could be, it only comes on when ambients are high or after a period of time running. (hot soak)
the FSM makes claims that heavy engine loads ,the ECU can command the A/C amp to turn off A/C. not sure yet how that happens. (kinda)
examples are Wide Open throttle, and low vacuum. (HIgh BARO)

engine hot.?
to be sure of this requires a IR gun reading of 3 places.
thermostat housing, top and bottom rad tanks. (i have refr.data on my over heat page)
some overheats are just the guage is no good. others are real , especially if you see fluid pushing out into overflow tank.


that A/C 235deg F. coolant switch might open after parking after a hot AC run. ( common in your experience i see)
This might trigger the A/C condenser to come on .
unplug this sensor to this test theory. (normally closed it is)

this sensor might have 2 functions,
1: shut down compressor if engine over heats. while driving or idling)
2: hot soak cool down , after engine is off. (still has power feed to it)
but none of this is in the Suzuki, manual, sorry to say. (many cars run fans for hot soak).

hope that helps.

the a/c on these are very tricky . (the electrical parts)

[gj68]

Thanks for the info. I will look into it when I have a chance. Maybe on Friday. I will let you know what I find.