am2 fuse blows and car wont start
 

Last friday my car wont start.We took it to the dealer they did the diagnosis for 91 bucks and they found out the am2 fuse blew up so they replaced it and charged me another $91 for labor.The car started but after 2 days it wont start again,right away I checked that same fuse and sure enough it blew up again.I replaced it and this time by myself because 91 bucks is just too much to replace a damn $2 fuse.So far it's still starting but I'm worried might happen again.What could be causing this?Help!!!

Have you done any recent electrical work? Sound system, neons, LEDs, etc?

I installed an aftermarket stereo but that was about 2 years ago.I have an 04 xb by the way.

Do you know what the am2 fuse is for? Knowing that will tell you what's up. I don't know, unfortunately.

Sounds like there is pretty obviously a short somewhere along the lines. Check the ignition coil for cracks, and check that your condenser hasn't melted. Those are most often the causes of AM2 to blow in Toyotas. You can remove the distributor and take it apart to check the condenser, I'd be willing to bet that's your problem.

BTW a replacement condenser is really cheap. Like under 30 I believe. A Cracked ignition coil is 100+, but hopefully yours is that condenser.

well.. the AM2 fuse is in control of a few things... one of them being.... the Starter system.

others are like the SRS airbags.. fuel injection system.. and the uhm... discharge warning system.

i would go back to the dealership and demand them to actually fix the problem.. you paid them a hefty amount and all they did was remedy the issue by replacing the fuse...

they didn't really fix the issue that was causing it to happen.... and of course.... you shouldn't pay any more when they do fix it.

That's a good point you have there, lol.

If some part connected to the am2 fuse is broken isnt it that the fuse should just keep blowing and wont let me start the car until the real problem is fixed?How come I'll be able to start the car and everything for a few days til that fuse blows up again?you think it's just dirt or corrosion somewhere?I read somewhere that corrosion on airbag sensors are known causes although that's on a camry.I dont know...

You can pretty easily correlate the camry info to the tc when it relates to issues such as this. I still maintain that you should check the compressor to see what it looks like though.

If there is a direct short to ground on a circuit that the AM2 fuse protects, then yes, the fuse should blow immediately. But, if that circuit is suffering from some sort of an eventual overload, then no, the fuse would not blow immediately, but would maintain the circuit until the overload reached its specified amperage.
If I were you, I would have the stealership that took your money fix the real issue rather than just replacing a fuse. An intermittent failure such as a randomly blowing fuse is not an easy thing to diagnose unless they can catch it at the exact moment it fails, so you may have to continue returning to them until the issue is permanently fixed!
Good Luck!

I have a 06 XB and decided to gut the interior down to the metal and dynamat the entire car, i posted a question here about the possability of the air bag light comming on after reinstalling the interior, I disconected the battery and it remained disconected the duration , after installing the sound barrier and reinstalling the interior and reinstally the front seat, all eletrical connections reconnected, i connected the battery, decided it was time to go for a ride and see how much diffrence the sound deadining made to the inside of car, turn the key to start and nothing happended, first thought battery must not be full charged , checked that and nope that wasent the problem, took me a while to figure out what all wasent getting power and thats when i found the AM2 fuse was burned, poped the burned fuse out and popped a new one in and bam , it blew, disconnected the neg side of battery and replaced the fuse again and then reconnected the neg terminal to battery and fuse didnt blow, turned the key over to start car and she started right up, took her to the dealer and got the run around that the battery back up for airbags provided a neg ground when i reconnected the battery the first time and that is why the fuse blew, I think they are full of ____ and ripped me off 96 bucks to check it out, I am pretty sure I have figured out what actually happended, The XB has a remote car starter on it and the installer did not install fuses on the polarity connections that were neg, just the posative sides were fused and when the battery was reconnected it instantly provided a un fused neg ground to the AM2 circuit and blew the fuse, any one have any Idea's, thoughts or better understanding to what i have figured out? please post , I would feel much better knowing my Box is gonna be ready to ride when i am, and no more issues with the AM2 fuse blowing.....

I agree with UV7 but I think before you go back to the dealer you should try and find out exactly when that fuse blows. If you start your car and just let it idle for an extended period of time does the fuse pop? Or is it only when your driving hitting bumps, accelerating, etc.? The more info you have when you go back to the dealer the better your chances are of having the problem fixed the right way...that is of course only if they listen to you.