radiator fans not turning on.....questions..

[Tyler]

is there a fuse that might have blown out???


if the fuse is not blown out.. can someone link me up to a site for a manual fan switch?

[awesomeame]

how do you know they ever turned on? i mean aren't they supposed to only come on at like 235* ?

imho you should find the problem, before installing something to hide/overrride your problem.

not sure about a '96, but on my 2002, there are 3 fan relays in the engine compartment fuse/relay panel, by the strut tower on the driver's side. your owner's manual will have a list of fuses & their purpose...that's a good place to start, anyway.

--matt

[cammed3800]

the fans should come on when the engine gets pretty warm, not just at 235, mine come on around 195-210

[Tyler]

yea... mine used to come on at 190ish..

and in heavy traffic... my temp gets up to about 210 and fans still not on... which lets my car get even hotter.


plus i've always planned on doing a manual fan switch.. just havent gotten around to doing it.

[awesomeame]

taken from GM service manual:

L36

The PCM commands low speed fans on under the following conditions:

-Engine coolant temperature exceeds approximately 105°C (221°F).
-When A/C is requested and the ambient temperature is greater than 10°C (50°F).
-A/C refrigerant pressure exceeds 1310 kPa (190 psi).
-After the vehicle is shut off if the engine coolant temperature at key-off is greater than 113°C (235°F) and system voltage is more than 12 volts. The fans will stay on for approximately 3 minutes.

The PCM commands high speed fans on under the following conditions:

-Engine coolant temperature reaches 110°C (230°F).
-A/C has been requested for at least 60 seconds.
-A/C refrigerant pressure exceeds 1896 kPa (275 psi).
-At least 6 seconds after low speed fans are commanded ON.
-When certain DTCs set.

there is one 40A and one 10A fuse in the underhood fuse panel that provide power to the fans/relays. there are 3 relays also in the underhood fuse panel.

hope this helps

--matt

[Tyler]

cool... how do i know if a relay is out or bad?

[awesomeame]

kinda hard to describe. the relay will have a little picture of how it's wired up, on the side of the relay....best to get someone with a little electronics experience to help you out.

basically you have to energize the coil inside the relay, and make sure you have continuity between certain pins on the relay, then de-energize the relay & make sure you have continuity between certain pins on the relay.

--matt

[Sunset01SS]

I have the same problem with my 96. I replaced the relays and it still doesn't work. So for now I just ran a wire from a fuse to the correct relay terminal so the fans are on whenever the ignintion is on. Works fine for a temporary fix. I'm sure a temperature sensor or something is bad. Anyone know exactly what makes them come on and where the part is to replace it?

[awesomeame]

the pcm tells them when to come on. you could also have a bad ground off one of the relays. if i can figure out how to make a screen capture, i could post up the wiring diagram....if someone knows how to do that email me 2002camaro@sympatico.ca

--matt

[Sunset01SS]

<blockquote>quote:</font><hr>Originally posted by awesomeame:
the pcm tells them when to come on.

--matt<hr></blockquote>
Right, but how does the PCM know what temp the car is? Has to have a sensor somewhere right?

[awesomeame]

oh yeah, of course [img]graemlins/dunce.gif[/img] it's directly under the TB.

'95-99 L36 GM P/N: 10096181 A/C DELCO P/N: 213-815
'00 L36 GM P/N: 12146312 A/C DELCO P/N: 213-310
'01-02 L36 GM P/N: 15326386 A/C DELCO P/N: 213-928

--matt

[awesomeame]

and here's a pic of the cooling fan system wiring..

http://www3.sympatico.ca/2002camaro/pics/cooling.gif

--matt

[Sunset01SS]

Cool, thanks. [img]smile.gif[/img]

[Tyler]

so where is a link to where i can make my own manual fan switch?