Live Chat:
: Hello. Yes what would cause a low temp fan to come on with the high temp fan in a 95 Pontiac
Bonneville. Both fans come on at the same time or low first then the high? Same time at 226 degrees then
they both shut off at around 200.

Answer: Is the A/C compressor on?

No. They do come on with the ac as soon as i turn it on and the only time it rises is when it is going slow or
stopped otherwise temp gauge rides around 200 when moving.

Since 226 degrees is the trigger for the low speed, i would think that there is a relay problem. Maybe the
high speed relay is stuck closed all the time and since it does not get power until the low comes on, it
would then power up the high fan.

I thought the low was 212.

No, low is about 226, high is about 250.

Why is a new car rides around 200 but my gauge keeps moving. Do you know what relay is the high
speed one.

Your Pontiac may have a radiator partially restricted- the car is 17 years old. And it depends on what temp
thermostat you have. When the T-stat open,s it will drop. Do not have a fuse box diagram right now, but
they should be labeled. There may even be 3.

I just replaced water pump , thermostat (195) and had it flushed and filled but i did put stop leak in it
before all this.

Stop leak can cause a restriction. If it is  not overheating, i would not worry about it.
If you need schematics, i can refer you to a site..

Thats what everyone keeps saying not to worry about it but do you think a really hot day will make it over
heat. Do you think it is all three i need to replace or just ohm them out and find bad one? Hey and thanks
very much for all the help to this is driving me nuts !

Without schematics, try swapping them around, or buy 1 new one and install one at a time. This is a just
an educated guess, but testing would be need to confirm a bad relay.

And these are in the fuse box by the firewall right


So why is there 3 two for the two speed fan and one for low speed?

If there are 3, they all work together. Not so much 2 for one and one for the other, they all sort of work
together. It is actually a pretty complicated circuit.

But they are all the same type?


Yea maybe should have that schematic just in case. But you dont think it could be the temp sensor (ect)?


Ok good cause i almost bought one today.

For sure not the coolant temperature sensor.

Do you think it will be ok on a really hot day?

No, i think it will  not overheat, the fans are coming on. This site will get you a
right away and
you can also ask the mechanics live for assistance testing just like we are now.

Ok so if you were me would you try and fix it?

Yes, i still would fix the issue. You never know if whatever is causing the problem,  it can go the other way,
and the fans not come on.

Thats true. Can i come back for help after i check the relays if i still need help? Just so im sure the low
speed one is the small one right, fan that is, sorry low temp passenger side?

Yes, on low fan.  I actually am going to be getting offline in a few minutes.

Ok but really want to thank u this site is awesome.

Your very welcome. Have a great night.
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Pontiac- Both Radiator Fans Come On- Mechanic Live Chat