1996 Oldsmobile Cutlass Supreme LS 3.1 46546 miles. Radiator fans not working. The temperature guage is working. The car over heats. I tried turning a/c on and 1 fan works the other 1 doesnt. I have located 2 fan relays in the right front engine compartment, switched them and the only the same fan from the a/c works. If the car overheats, do both fans kick on? Are there any other fuses, switches, relays? Please help! any information will be greatly appreciated. Just checked the other motor with 12v and it works.

Okay. First thing you want to check is the number 1 and 2 mazi fuses in the underhood electrical center (where the relays are). Number 1 and number 2 should both have 60AMP big-assed fuses in there. Test them to be sure that one has not blown. The maxifuses are the two in the far RIGHT positions (you have normal fuses on the left of the box, relays at the bottom, and then postions for 4 maxifues, but they are numbered BACKWARDS)

If you don't have at least a test light, then you will need to get one to test your power. I recommend a good voltmeter (I think walmart sells a REALLY GOOD one for like $25 that is DIGITAL, and it also test continuity (to check for broken wires). That will help you test the rest of it.

Second, you will want to test the relay of the one that is not working to be sure it gets POWER. My book lists the pin number, that will not really help you. Find the HOT AT ALL TIME wire from the working relay and then test the same position on the not working one. If they are both hot, then your power is good.

The next thing to check is the GROUND. The easist way to do this is to run a JUMPER WIRE from the HOT AT ALL TIMES position in the relay to the opposite side. Seeing my 1996 book says that they are the BIG relays, then they are across from each other. If the blades look like this:

__

l l l

l

Then you will connect the two wires that are on the opposite sides (you don't use the middle one). Connecting the HOT to the one across with a piece of wire should turn the cooling fan ON. Do this to the GOOD ONE FIRST so you can see how it does. This is also the way that the HARD WIREING is done to manually turn the cooling fans on.

If you don't have power, then replace the MAXIFUSE or test for a BROKEN WIRE (the continuity test will make the voltmeter BEEP if you touch 2 ends of a wire, and they are GOOD. If you connect the voltmeter to the HOT position on the relay, then connect the other end to the MAXIFUSE, if it BEEPS, the wire is GOOD. If not, then make sure you are hooked up to the correct wire, and if still no beep, you have a broken wire.

That should tell you if it works. If you do that, and it still does not work, you will need to test your wires to the PCM. If those are good, then it means either your PCM is messed up, or the coolant temp sender is bad.

The coolant temp sender for your car is a 3 wire one. Just because the GAUGE is working, does not mean the PCM wires are. It is located under the throttle body (at least my Grand Prix has the 3 wire sensor instead of the older 2 seperate senders).