[sub7rox]

I have a 99 Toyota camry V6. It overheats because the radiator fans do not kick on. I parked my car and let it run and waited till it started overheating. Popped the hood and no fans running. I am afraid to take it to a mechanic because 90% of them rip you off. What could cause this to happen other than the fuse?

[TxGreaseMonkey]

Radiator fan failure is one of the leading causes of engines overheating, often resulting in warped aluminum heads, blown head gaskets, and damaged valves.

1. Check all underhood and underdash fuses with a test light or multimeter:

a. Multimeter. Set multimeter to DCV, turn ignition switch to ON (Position II), touch the black test lead to ground, and touch the red test lead, in turn, to each test point on the fuse. The meter should record 12+ volts. Voltage must be recorded at each test point on a fuse; otherwise, the fuse is bad.

An alternative method, which is very fast, is to set your multimeter to audible ohms, DISCONNECT THE NEGATIVE BATTERY TERMINAL (or you could blow the fuse in the multimeter), and touch the red and black test leads to the test points on each fuse. When you hear the meter buzz, you know the fuse is good. If your meter doesn't have audible ohms, but it does have ohms, you can still use this method--just read the meter instead. The alternative methods perform a continuity test on the fuse. Just remember to de-energize the circuits, by disconnecting the negative battery terminal, and record any radio activation codes first.

b. Test Light. Turn ignition switch to ON (Position II), connect alligator clip to vehicle ground, and touch the probe to each test point on the fuse. The test light must come on at each test point on a fuse; otherwise, the fuse is bad.

These methods allow you to accurately and quickly check all underhood and underdash fuses in several minutes, even in dark, cramped locations. They eliminate the possibility of removing and replacing the fuse in the wrong slot. Should a fuse test bad, use the fuse puller, provided in the underdash fuse/relay box, to remove it.

2. Jump fan motor and ensure it runs. Disconnect the fan motor connector and attach jump leads to the battery.

3. Check/replace the Engine Coolant Temperature (ECT) Switch (not the ECT Sensor).

4. Check/replace cooling fan relay, which is usually located in the underhood fuse/relay box.