Hoping someone can help me figure this out as I am not too familiar with how to diagnose and fix something like this.

The situation:
This winter I had an intermittent no start issue with my 05 SR5, which occurred only on a few extremely cold mornings. A check of the battery and alternator showed no problems. I figured it was the starter beginning to go out, but since it wasn't happening very often and the 4runner isn't a daily driver, I figured I'd wait for warmer weather to deal with the starter.
Today I had some time so figured I'd pull the starter and rebuild it with a kit I purchased. Nothing went right.
- I started by disconnecting the negative terminal on the battery.
- next I moved the hard brake line in the wheel well out of the way.
- next I began trying to loosen the cable that runs to the starter (the bolted on one, not the plug).
- I could not get the bolt off, even with copious amount of PB blaster. eventually the whole stud began spinning, so said heck with it and put it all back together.
- I reconnected the negative battery cable and went to start the car. It wouldn't start, just a little click each time.
- I figured that maybe the cable connection on the starter was not good since I had trouble re-tightening it, so I disconnected the battery and went back in to tighten the cable on the starter. After a long time, I was able to tighten it.
- I went back to reconnect the battery. when I put the terminal back on, I had sparks and lots of heat at the cable, slightly melting the post on the battery!
- now there is no power at all. no dash lights, no nothing. I did a visual check on all the fuses under the hood and inside the panel by the driver side door. didn't see any blown fuses.

What the heck happened and how do I fix it?

When you were trying to break the nut loose holding the cable to the starter, did you have a wrench on the back? If not, it sounds like you somehow broke the stud loose internally from the starter body. I'm assuming there's some kind of insulator internally and a buss bar or cable that connects it elsewhere inside the starter housing. If you managed to bust this with all the twisting/turning trying to loosen/tighten it then you may have torn this connection loose. Worst case the connection has shorted against the inside of the starter housing.

When you re-connected the ground you basically have a dead short through the starter circuit. So you didn't blow a bunch of little fuses but smoked a big main one somewhere. I'm not even sure if there is a fuse between the starter and battery terminal. There's another fuse panel under the hood that contains the larger fuses and relays. Better start checking there.

First thing you need to do is get that starter out and take it somewhere to get checked, or better yet replace it. I think that's the root of your problems. After that hopefully you just smoked one of the main fuses and didn't do any serious damage to the ECU or other sensitive circuits.

http://4runnerclub.com/i/4r_files/fs...er/h/em03m.pdf

You defintely have a direct short, and it can only be in the starter, I sure hope you blew a fuse or relay somewhere but I'm afraid you may have smoked the ECM.

Ooh, this sounds pretty bad. I did a visual check of the fuses, but didn't find any that were visibly blown. I'll have to try to get a multimeter and check them. Not sure how to check the relays though and I doubt I'll get that starter out as I couldn't get it loose after trying for a few hours. I don't have a trusty mechanic that I'd trust to figure this out efficiently without spending a bunch of my money, and sending it to the dealership isn't a better option really. Its a 15 year old truck with lots of dings and dents, 200k miles, plenty of rust, and stop leak keeping the small head gasket leak at bay for the last 20k miles. I think this might be the end. Its sooner than I planned, but not entirely unexpected. Very bummed about this. I've been wrenching on my cars for over 10 years and have never had anything like this happen. ��

https://www.google.com/search?q=how+...hrome&ie=UTF-8

Remove both the starter with the cable attached? It is part of a harness, but looks like it could be separated. Replace starter and cable and see what happens, it'll either have power and hopefully start, or you'll have to proceed with more diagnosis. Look up 4runner starter removal examples on youtube and watch 2 or 3 times so you have a better idea of what you going to do. Here's one;

2003 Toyota 4runner starter removal
https://www.youtube.com/watch?v=2A3mjWpsQR0

Edit Section: Edited out due to lock nut on inside of starter connection.

Call Main Line Overland and see who they recommend for mechanics. They installed my Bilstein 6112/5160s and definitely wrench a lot. They might even be able to fix it for you.

https://www.mainlineoverland.com/

Just had this, there should be a nut on the inside of the positive cable connection, you'll probably need a thin wrench wrench to hold it, but it should counter the outside nut when you try to twist it off. I am going to edit my last post about cutting the cable, being it's probably not the best option if you have a lock nut to work with.

Edit; I have a new starter in front of me and the lock nut on the positive connection has a partial plastic cover/insulator over it. To clarify, this lock nut is located between the cable and the starter case. I'd guess your insulator is partially broken off and that's why the stud turns when you try to loosen the outer nut. Try to get a 14mm thin open end wrench on the lock nut, or if you can't do that you should be able to pry/break off more of the insulator and get a normal wrench on it.

[QUOTE=bobdod04;2992384
- I went back to reconnect the battery. when I put the terminal back on, I had sparks and lots of heat at the cable, slightly melting the post on the battery!
- now there is no power at all. no dash lights, no nothing. I did a visual check on all the fuses under the hood and inside the panel by the driver side door. didn't see any blown fuses.

What the heck happened and how do I fix it?[/QUOTE]

There is no fuse in the main cable between the battery and the starter. The current is normally limited by the internal impedance of the starter, as well as by the cable resistance and the internal battery resistance. As others have stated, your work on the starter terminal likely resulted in a dead short at the starter. This allowed the battery to attempt to deliver max current (600 amps or more), and may well have damaged the battery internally, since you say the post was melting.

There's no reason to expect any fuses to have blown, or for the ECU to be bad. Neither the ECU nor any fuses were in the path of all that current. My guess is your battery is toast. A simple test is to pull out your multimeter and check the voltage across the battery terminals. Should be 12V or more.

And, by the way, how did you originally conclude the battery and alternator were OK and thus the problem must be the starter? 99% of intermittent starting problems are either a poor connection at the battery or starter, or an intermittent cell internal to the battery. Both of those conditions can be temperature sensitive. (And remember, there are four connections involved in the high current starter circuit - both battery terminals, the large starter cable to starter, and battery ground cable to frame. All of those need to be squeaky clean and tight.)

The battery was fairly new and I had advance Auto test the battery and the alternator. Double checked the battery at pepboys also since it was still under their warrantee.

I guess I'll need to try again to get that starter out and likely replace the negative line from the battery to the start? Thanks for the advice, I feel as little better knowing that I may not have fried the ECU.

Also check the continuity of your battery ground cable. You may have burned that off with the short.

Had a few minutes with the multimeter today. Can confirm the battery is fully toasted. Reads 0.00 volts vs my other car that reads 12.4. will try to test continuity in the battery cables later when I have more time.

So, at this point I know for certain that I need a new battery and starter.

Another question, if I am not 100% certain that the battery wires are still good and I replace the starter and go to reconnect the battery, will I wind up frying something again, or will it just not start? Sorry if this is a dumb question. I am not great with electrical stuff (obviously).

It's tough to do a real continuity test on battery cables. You'll get some low resistance value even if half the fine wire strands are burn through. It only takes one tiny strand to carry the small current the meter reads.

If there's any doubt (you saw/smelled them get hot, smoke, etc.) then replace them. You can check some threads on here about the "big 3 upgrade" to get quite a bit of information about the routing of the various cables (battery to starter, battery to alternator, ground).

If you can do a complete visiual inspection of the positive/+ battery cable to insure it hasn't melted the insulation and touching/grounded out on any metal then you should be fine to install the new battery and hook it up, but I would still as a safety measure do a continuity test on the positive cable to ground, in other words one probe on the + cable and the other probe on the engine block, then the chassis and then a few other metal places to be sure the + cable isn't grounded out, then you should be fine.

Another safety measure when connecting the battery is too connect the + cable on the battery first and then very very quickly tap the -/negative cable on the negative battery post, if you get a spark then you still have an issue with the positive cable being grounded, just an FYI, if you have any doors opened, any switch on, etc. you will get a spark when you tap that cable on the post, make sure everything electrical is OFF, if you have a dead short you will get a big spark!

When you connect the battery cable to the new starter be sure that stud doesn't rotate or you may have the same issue again.

I want to keep this updated in case someone has a similar situation.

I finally had a bit of time to get back into this and was able to do the following so far:
1. removed the old starter
2. installed new starter
3. tested continuity of wiring and checked fuses

I did not get a chance to try to start it since the battery is dead and I need to get that resolved still.

below are some details:

Removing the starter:
1. Removed the driver's side wheel
2. Removed the black plastic "flap" in the wheel well
3. removed 3 bolts holding the brackets on the brake line to allow for a little bit of movement in that line.
4. removed the very back portion of the skid plate (two bolts).
5. removed the positive cable from the starter (turned the 12mm nut while holding the 14mm with a spanner). This actually was the most difficult part of the job as the threads on the stud and the 12mm nut were very corroded and I had a heck of a time trying to get that nut to come off the stud on the starter.
6. removed the plug right under the positive cable connection. this one needs a little tab on the bottom of it pushed, while pulling the plug out.
7. removed the lower 14mm starter bolt from underneath using a ratchet and breaker bar. Had it soaked in PB Blaster for a while and it came out easy. There is not a lot of room and the length of the socket as well as the ratchet will come into play. I tried a few that I had until I found one that worked in the available space and was long enough to provide sufficient leverage. The heads on these bolts are "low profile" so you don't have a lot to grab onto with your socket. Be very careful not to round off the bolt and use a good quality socket. With so little room in there, I don't even want to think about what would happen if one of these bolts was rounded off and you couldn't get a socket on it anymore.
8. top 14mm starter bolt was a little rough. I saw video of someone claiming they got it loose with a ratchet and breaker bar from the top (behind the engine). I tried that but could not get enough room for that to work. I first was able to put a wrench on it from the side through the wheel well, but wound up partially rounding off the bolt trying to break it loose. I then ended up putting a socket wrench on it from underneath and had just enough room to get it to turn (1 click at a a time) with that rear skid plate removed. So bottom line is that both 14mm starter bolts can be reached from underneath with a socket wrench and a breaker bar, but the length of the wrench/breaker bar is key (too long wont fit and too short won't give you the leverage you need.
9. I was able to remove the old starter through the wheel-well by working it past the brake line (with the 3 brackets unbolted). It was a bit of a squeeze, but it came out just fine without any damage to the brake line.
10. I decided to drop in the new start from the top (gravity is your friend). I removed the little metal bracket located under the oil filler neck (not sure what this is for since it does nothing). I also removed the bracket holding some vent hoses directly opposite that metal bracket on the oil filler neck. With these brackets out of the way I had plenty of room to drop the new starter down into place through the engine bay. I was then able to get it into its final location through the wheel well.
11. bolted everything back up the same as way as above steps.

I used a multimeter to check the cable running from the battery to the starter. The lug on the starter end was pretty corroded so I polished it up with some sand paper and the cable tested fine after that with no resistance shown. I also tested the ground cable in various locations from the battery lug. All showed good connectivity with no resistance.

I still need to get a functional battery in there to see if it will start. The current battery was drained in the initial incident and reads 0.0 volts currently. I will be taking it to pep-boys for them to check if its toast or not. I will update this thread after I get functional battery (either recharged current battery or a new replacement).

Hoping it starts right up with a good battery. If not, I'll be looking for help from you.