Question: I have a 2004 Oldsmobile Alero, 4 cylinder, and a few nights ago I went to start it, but it
wouldn't start. The ignition made no noise at all, no clicking to indicate a dead battery, no cranking
noise, or anything like that. I could hear the fuel system starting up, but that was all. None of the
dashboard lights car on either. I called AAA, and they sent out the vehicle. The person who showed
up immediately found it was not the battery, and proceeded to check if it was the starter or something
else. He found that it was a shortage, which had caused the 40A fuse for the Ignition Switch Battery to
blow. He didn't tell me that specifically at the time, though, and merely said there was a shortage in
the ignition somewhere. I had the car towed to Pepboys, and the next morning they said it was the
Ignition lock Cylinder, which sounded a bit off to me since I was having no problems turning the key.

Before they did any work on it, we had it towed home and checked it ourselves, and found the
problem with the
fuse that had been found my the AAA guy. After a ton of research, we figured the
problem must be the ignition coil, which we then had tested. The coil was blown and we replaced it.
The car didn't start, but the fuse didn't blow and the battery was dead, so we charge the battery. The
car was able to start after that, but when we turned the car off again the 40A fuse had blown once
more. I've done more research, and found that the problem could either be a wire grounding out
somewhere, or the alarm remote could be interferring with the car somehow. The problem with the
second theory, though, is that when I bought my car used it did not come with a car alarm remote. Is
there anything else that could be causing the problem?
Answer: That is correct. If the car does not have an alarm, that would not be the problem. The
ignition coil cannot blow a fuse. An
ignition switch or key cylinder cannot blow it either. The ignition
switch sends power to most of the car systems. If there was a problem with that, there would be a low
voltage problem, not a blown fuse. You have a short circuit somewhere. You are going to need to
get a
repair manual at least get a wiring diagram, test light and digital multimeter and trace the wiring
for all of the components that is powered up by that fuse. It most likely will not be a bad part, but
rather a shorted wire.

This can be a very difficult thing to find, so I would suggest taking it to a mechanic and not trying to
diagnose this yourself.In order to blow a 40 amp fuse, this would indicate a large wire, probably
orange or red is shorted. Checking under the dash for shorted wires coming off the ignition switch
would be the first thing to check.

Many times non-factory alarms are installed. Many wires need to be cut and spliced. Then when the
system fails, people will have the wires cut and put back to the factory original. This causes a lot of
unnecessary wire cutting, re-routing and repairing and is a common place for shorted wires.
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2004 Oldsmobile Alero Blows 40 amp ignition Fuse