Mechanics

IT BLOWS 4AMP STARTER FUSE WHEN KEY TURNE

2000 Toyota Camry

Electrical problem
2000 Toyota Camry 4 cyl Front Wheel Drive Automatic

If you start car by jumping starter, it blows the 10amp gauge fuse after a few minutes of run time. I have replaced the PCM, the neutral safety switch, and pulled the relay to the fuel pump. It still blows the 4amp starter fuse when ignition is in start position after all of that. The engine was recently rebuilt and all connectors are in their receptacles, and all grounds are hooked up. I idled the car for 5 hours with no problem, and drove it for 30 miles before this happened after the motor was rebuilt. The only problem that I was concerned with before this happened was that the temperature would have to get in the red before the cooling fans would come on. And the ac didnt work even though it did before the rebuild.
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Camry Owner 2000
May 8, 2010.




Hi Camry Owner 2000,

Thank you for the donation.

For the temperature to reach HOT before the fan starts working indicates a possible fault with the fan switch.

The fuses blowing indicates a shorting and it could be bare wires that is touching somewhere causing the shorting.

Such faults would not be easy to diagnose.

You mentioned 2 fuses blowing? Do they blow when something is operated?

KHLow2008
May 16, 2010.
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?

Tiny
Camry Owner 2000
May 19, 2010.
I am not sure which fuse you are referring to and there are no 14 or 4 A fuses. Can you point out the fuse location for me from the diagrams?


http://www.2carpros.com/forum/automotive_pictures/192750_FuseBoxHood00CamryFig02_1.jpg



http://www.2carpros.com/forum/automotive_pictures/192750_FuseBoxHood00CamryFig09_1.jpg



The fan switch ( water temperature switch ) is located at right front of engine. Item # 7 in diagram.


http://www.2carpros.com/forum/automotive_pictures/192750_EngineComp00CamryFig01_1.jpg


KHLow2008
May 19, 2010.
It is the 5amp starter fuse and the 30 amp power fuse (for medium current) apologies for misinformation.

Tiny
Camry Owner 2000
May 20, 2010.
Here are the components that are powered by the respective fuses. Any fault with the respective compents would cause the fuse tp blow and it is not going to be easy to diagnose.

If running the engine without shifting into any gears and the fuse blows, the two items that would cause the fuse to blow would be the Engine PCM or combination meters.

Starter fuse 5 A =
Combination meter
Electronically Controlled Transmission an A/T indicator
Engine Control
Starting and ignition

Power ( 30 A) =
Moon roof
Power seat
Power Windows

Does the Powe fuse blows everytime the engine is running?

KHLow2008
May 20, 2010.
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?
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Tiny
Camry Owner 2000
Jun 17, 2010.
The starter fuse is related to the shifter and you could be correct about the problem being near the shifter.

You mentioned the gauge fuse blowing, so this is not the starter fuse?

The power fuse could be a separate issue and it is conincidence that it is blowing the fuse. It definitely is a short somewhere and you can test it by operating the different components to test if any is not working correctly before the fuse blows.

KHLow2008
Jun 18, 2010.
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.

Tiny
Camry Owner 2000
Jun 21, 2010.
The shorting of the gauge fuse seems to be from the starter circuit.

Unplug the starter relay and test if the fuse blows.

For the overheating, if unplugging the fan switch connector turns on the fan, then either there is insufficient coolant iin system or the fan switch is faulty. If coolant level is correct at radiator, replace the fan switch.

KHLow2008
Jun 22, 2010.
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.

Tiny
Camry Owner 2000
Jun 22, 2010.

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