2000 Toyota Camry It blows 4 amp starter fuse when key is turned

Yes if I unplug the starter and jump it from the battery I can actually get the car to run. But soon it will either blow the 10amp dashboard(guage) fuse or a 14amp fuse that goes to something that controls the dash power also. But if I just leave the car ignition in the on position but not run the engine none of the fuses blow. By the way can a PCM be tested out of the car? If not can a PCM blow fuses? I also have unplugged the two temperature sensors and it still blew the 4amp fuse on start-up. I also understand that the ac is supposed to turn a cooling fan on low when switched on and both fans on low when operating temp. Is reached. Where is the fan switch?

It is the 5amp starter fuse and the 30 amp power fuse (for medium current) apologies for misinformation.

No the fuse didn't blow when I just drove it a couple miles today, but a few days ago the 10amp gauge fuse blew when I drove it a few feet off the ramps it was on. I have purchased another ECM (PCM) and am convinced that the problem is not with that. I thought the short was around the shifter and took that area apart as well, but no melted or bare wire. Is there a likely area the short could be in or is it anywhere in the car is game? Wouldn't it have to be something pretty major to blow the power fuse? Could the problem be linked with the low temp switch and ac issue? Where is the fan switch located, is it just the low temp sensor? Does all of this point to a loose wire causing all of this, or could it still be a replaceable component?

No it is not the starter fuse, that is 5amp and blows consistently when ignition is in the start position. I do have something to report of interest. I unhooked the neutral safety switch and tried to get the 10 amp gauge fuse to blow(its on the diagram you showed me) but it didnt, that is also when I drove the car to auto zone. Then I hooked up the neutral safety switch and it blew the 10 amp gauge fuse. But I have already replaced the switch with another one from the junk yard so I am thinking it is in the wires them selves. Also can you tell me what to do to fix the cooling fans to come on at operating temp because my car has to heat up to red line before they come on and I just dont think it is good for a new engine to goto redline over and over.

Can you tell me where the fan switch is? If I unplug the temperature sensor nothing happens to the fans. So I assume there is another thing you are talking about. On the subject of blowing the fuse, to blow the gauge fuse the vehicle must be running and apparently moving, I dont know exactly what has to be executed to make it blow. All I have noticed is that when the neutral safety switch is unplugged it apparently doesn't blow, even though the starter fuse will. I hope this helps.

I replaced the one you spoke of and the fans still wont come on until red line. I believe that that one is the high temp switch. (As when I unplugged it the fans come on full blast not on low) The fans dont come on when when I unplug the low temp switch. Does that signify a short in that line, maybe? Also I did as you asked on the neutral safety switch no. 6 and a ground. I got continuity but only in an increment of full. Does that go directly to the starter fuse or starter relay, or does it go through the ecm first? I really appreciate your help, I feel we are going to find the solution soon.

I have checked lessened continuity when hot and it is good, so the low temp switch is not the problem. I checked voltage through the wires and it would only register just above zero. By the way when I first checked it, it was going up and down with I think spark from the engine. Is it possible for the spark plug wires or the coil pack to feed back through the low temp wires and blow the computer? After I moved the wires away from the coil pack it stopped surging. (It will shock you pretty bad when the engine is running) So what does it mean if no power is coming to the low temp switch? Is that the wire I need to track and see if there is a spot thats bad? Or could the computer be bad and causing all of the problems?(Because of feedback from coil) Because I have replaced the computer twice already so I was convinced it was not the problem. (But I was afraid of blowing the computer over and over because of another problem that needed addressing.)

I tested the low temp switch again and it is sending 5-6 volts, but I think it should be 12. Also if I unplug the low temp switch I think the fan should come on low but it doesn't. Any ideas like a resistor or something, I can't figure it out.

BTW I looked and found I did pinch the harness so I redid the wiring and now the problem is fixed for the blown of the fuse problem.

In response to not having two speed fan, I figured its voltage gets sent through a resistor, like the fan inside the car. That is how the fan could have a high and a low. Coolant does not boil out when the temp is high, but the fans come on probably just before that happens. Once the temp goes down the fans shut off till it gets hot again. Radiator flows well, no detectable clogs. The low temp switch is located right next to the temperature sensor on the tube exiting the engine or return flow to the radiator. (Not the water cock where the thermostat is located.) I have tested the resistance on the low temp switch. When cold no resistance, once operating temp is reached according to the temp gauge, there is resistance to the flow of electricity. I really think that there has to be a resistor in line that is bad, but I dont know how to find its location.