2007 Camry, changed alternator and missed most important step. disconnect battery. power line arched off engine I now have no spark

Sounds like it's time to start checking fuses. Do you have a 12 volt Test Light....or....a Digital Volt Ohm Meter? Look in the fuse box under hood. Do You see a 80/100 amp Fuse?

Checked all fusesunder dash and hood except I can't get the 2nd large fuse behind the large one with the copper tab on it out.plastic tab a pain

Also when I arced power line nothing was hooked up, alternator wasn't even installed yet

And no on the 80\100 amp fuse

Ok....I am going to assume the Engine in this vehicle is a 4 cyl. I also assume the wire that shorted to ground is the fat wire attached to the Alt. Am I correct? That wire has 2 protection devices in line....a 120 amp Alt fuse located in the under hood fuse/relay box...and a fusible link which is part of the wire itself. Suggest you use a 12v test light or a DVOM to check that 120amp fuse.

I have power to the alt

"I have power to the ait" What does that mean? How are you checking for "power"?

Used volt meter on main power to alt. Got 12

WELL....I am not sure where you are with that volt meter. Suggest you find that 120 amp ALT Fuse under the hood and use your VM to see if there is 12 volts DC on both sides of that fuse. You can also Check the wire that accidentally sparked to ground and see if you have 12 volts DC at the ALT end of that wire. What color kis the wire that arched? If you have 12v on the FAT wire going to the Alt....then we have to start trobleshooting the Ignition System Circuit. Is this a 4 cyl Engine?

This is the last fuse to check. I can't get it out

And yes I did push the small tab, it won't come out

Look under the Fuse Box Cover. How is that fuse labeled? Now comes the hard part. I think that fuse is held in with bolts. You might have to remove that fuse box for disassembly. If you can ID the fuse...then we can Google the procedure for removal, Don't forget to DC the Battery.

The one next to it is the one bolted down, had that one out, it was all good, this one has a small tab ya move with a small screwdriver. I'm using small channel locks to pull on it but it won't come out. Don't want to pull too hard. Already chewed the plastic a little

Those 2 aren't labeled, and the owners manual is a joke!! There wasn't even a belt diagram on the fan shroud or owners manual

Check this out.

Second try

As you can now see....that !@#$%^ fuse is bolted in. It has windows on the side so you can see if it's blown. Can you see the windows with the fuse in place? It appears to be more than ONE FUSE.

Aaahh!! Bolted from bottom. 1st one was bolted on top, wouldn't think both would be bolted especially with the plastic tab on the side.

After pulling the front fuse I was able to check 2nd one. All good

Ok...so now let's redefine the issue. This is a 4cyl Engine. Correct? The Engine Cranks over well...but...will not fire up(Start) Correct? You appear to Fuel Pressure but no Spark? id you check for spark at each ignition coil?

Suggest you check 2 fuses. Ignition #1...and...Ignition #2....located under the Driver's Side Dash.

Shouldi be reading any output on these 4 prongs while starting, or I should say attempting to start?

Also I have checked every fuse both under the hood and dash

Those 4 prongs got to the Voltage Regulator onside the ALT. Unknown if you will see any V coming out of those prongs. However...The prong that takes the Blue wire goes to the ECM. The Prong that takes the Red wire goes to a 10 amp gauges fuse #1. The Prong that takes the Yellow wire goes to the Charge Indicator Lamp on the Dash...then....a 7.5 amp gauge fuse #2. The Green with a Red stripe goes to the 7.5 amp Alt Fuse. Do you have any Volts on the 4 WIRES ...when the key is ON? BTW That big FAT BLACK WIRE....do you have 12 volts on the end of that wire...even with the KEY OFF? IF NO.....It's .back to square ONE.

Could any of this also have to do with theft deference system. I've heard that disconnecting the battery can trigger certain systems.

I do have 12v to the big blk wire, that was check point 1. Wasn't sure on output in this case. When I arced it the alt wasn't even in. I wasn't sure if there should be an out put during initial start or if it had to be fully running to get one

Regarding the Theft Deterrent System. Indeed this could cause a no start condition. I cannot remember what the Manual Reset procedure is. Suggest you check out the Owner's Manual or...a Google Search. That fat black wire to the Alt is connected to the pos. side of the Battery.....and therefore should have 12v all the time . Thist voltage should go to about 14v when the Engine is running indicating the Alt. is attempting to charge the Battery. Why not attempt a restart with the spare key? ...and...lets find out more about the Theft DS.

The owners manual should be cut into 3 inch strips and put on a roll. To summarize it says consult dealer for all situations. There wasn't even a serpentene belt orientation diagram. So back to the question, should there be power output during cranking cuz if that's the case I've had a bad alt all along

Concerning those 4 prongs on the LT. From where I sit...they appear to be INPUTS from the ECM Computer and various Fuses as noted above, you should be seeing voltage at the 4 way connector that plugs into the Alt.... with the Ignition Key On. A Google search should yield info concerning the TDS if one exists. Welcome to the world of today's complicated vehicles. Just think what the average Mechanic of today has to know in order to make a living.

I have 12 volts at all 4 points on the plug

Just took new alt and had that checked,all good.

UNREAL!!!!!!!! It seems that during this whole process I bumped or tugged this green wire. When re-installing the new alt I bumped it enough that it pulled out the rest of way. Put it back and it started right up!! Thanks for the input, car now running

Well ....seems Christmas comes early for some folks. would be nice to know where that green wire goes. Well ....anyway. Nice job and good luck.

Just had another Senior Moment. IF that Green Wire runs along side a RED wire....and....seems to go down to the front of the Engine....you might have inadvertently DC the CRANK SHAFT SENSOR. NO Crank(RPM) Signal to the Computer....the Computer will not see the Engine Crankshaft rotate.....thus.....no spark...no fuel. Seems this vehicle provided a new LEARNING EXPERIENCE FOR ALL INVOLVED. What say you folks out there?

Hoorah....let's give 2016 a fond farewell.

Yes it was the crank sensor

And "Say hello to my little friend"......2017. I hope we can continue to help you folks out. Cheers.

Hi my question is all Toyota alrenator car are the same size, because I took my and take to the place to rebuilt and they give me one look same but now can’t fit in my car, my question why? I has to adjust the brakes, please I need some assistance thank you

What is the Make....Model.....Year.....and Engine type of this vehicle.?

T9V....car fixed?

Just changed the alternator on a 2007 Toyota Camry but it still turns off after disconnecting the battery?.. any guesses what could be?. The big blue fuse starter or crank sensor?. Need help don't know how to take the blue fuse out?.

Genaro....could you provide some history proceeding the issue with this vehicle? What made you decide the Alt. needed to be changed?

I disconnected the battery & the car shut off.. to my knowledge the alternator is the one that causes this problem?. But still the same?. Don't know if is a faulty alternator oh could b the alternator fuse but don't know how to get it out.

Can you take a photo of said fuse and post it?

That fuse..

That fuse may be bolted in place. Might have to remove entire assembly. Perhaps we should start from square one. Does this vehicle CRANK OVER....like the battery and starter motor are in good shape?

Yes the vehicle starts but it shuts off after disconnecting the battery. & I just replaced the alternator 2 days ago.. that's y my guess it could b that one fuse but don't know how to take it off.

I would be curious to know why you expect the engine to run with the battery DC? The Computer is reset when the 12volt battery is DC. The computer on a 1997 Camry is in control of the Fuel...Ignition.....AND Charging Systems. Seems to me....these systems would fail to function when a battery cable is DC. Any other opinions out there?

Well.....genaro.....do you continue to have issues with your vehicle?

Hey Tony I have the 2007 Camry 2.4l and I arched the fat black wire but mine has power to the car except no fuel or spark. Do you have any suggestions as to which fuses to check? Thanks.

Ck.. The ALT FUSE under hood fuse relay box. You need a 12 volt test light to check it. Its bolted in place.. Get back with result.