Robsteeler66

My son tried to jumpstart my truck. It has been sitting a while and the battery was flat. He put the pos to the neg when he put on the cables. Needless to say he couldn't get it to start. When I got there I noticed what he did and switched them. It still didn't work so I was worried that he damaged the battery. I got a new battery still the same. Now I'm worried that he damaged the voltage regulator or the ECU. I think it must me the ECU since the headlights still come on. I don't know if I can just pick up an ECU on ebay. I looked and there are a lot off them. What are the differences? Can I use a 4x2 or A/T ECU?. My truck is a basic 1990 4x4 M/T 22R-E. Do I need an ECU that says all of those things on it or are they all the same?

rworegon

Start by checking all the fuses.

4Crawler

iTrader: (3)

ECU applications:

Robsteeler66

I will check the fuses. Is there a specific relay that may be damaged? That ECU chart is awesome, exactly what I need. Thanks guys!

ChefYota4x4

iTrader: (5)

Rob, .........

I'll bet cash money that it's the 80A Fuse in the Fusible Link Box by the battery........ Peek in there and let us know, k? Also check the IGN fuse in the kick panel by the drivers foot.... see whatcha find, and get back to us.

ChefYota4x4

iTrader: (5)

PS> The actual fusible link wire from the positive terminal to the fusible link box can literally 'blow' as well, so make sure that's intact, also.

Stuwy123

iTrader: (1)

My vote is you blew the 80A fuse as well.
Check them closely, aka take them out to check them.
They are sometimes hard to see under flashlight or dim light.

ChefYota4x4

iTrader: (5)

Stuwy....

Hey Rob, let us know the diagnosis/prognosis/etc., etc., k? lol....

Terrys87

iTrader: (1)

Robsteeler66..My nephew did the same thing to his 89 22re. Here is the 80Amp fuse that is most likely blown and steps to get it out. The fusible link is the short wire attached to the positive cable. Parts stores have the fuse for 3 or 4 dollars if I recall right.



All of the other fuses lift up and out. The 80 Amp you have to pry this tab to the firewall and push out the bottom.


Here it is mounted to the Fuse. It mounts behind the wires. I usually have to take a 8mm socket to the screws the first time. They can be TIGHT.

Robsteeler66

That's awesome guys, thanks for the pics. I will check it tomorrow. I've been away yesterday and just got back. It's too dark right now on the east coast!

ThatGuy1295

Smack him!!! Why would you put the pos to the neg. Regardless of age,,, what is wrong with you? I mean if your old enough to know what jumper cables are, then you should know RED is +.

Jesus!!

Sensei

I believe his son made a mistake but not worthy of a beating.... he learned a lesson. Plenty of vehicle have black cables on both pos and neg with no color caps/terminal protectors. This may or may not be the case with the OP's rig, I don't know. Smackin the kid down doesn't do much for his confidence.

ThatGuy1295

Ohh. You took me seriously didn't you? Ya don't do that.
I was kidding about smacking

But gees,, if you don't know or your not sure which one goes where, don't do it.
You better hope he doesn't make the same mistake with his sexual preference.

tazz76

my 83 has a red neg and black positive very confusing sometimes...but the 80 amp fuse is the first place id look

bob200587

How old is the dummy?

nothingbetter

hey now. No sense being mean. I remember being young and wanting to "impress" with how much I knew and having it go terribly wrong and being ashamed. I've since learned its easier to ask questions and be sure of what your doing. But man was it ever a steep learning curve!

I hope it just the fuse!

4Crawler

iTrader: (3)

Previous owner of my '85 apparently stuck in a new battery backwards and I think he ended up replacing quite a bit of stuff according to the pile of shop receipts he had. I even had to fix a few things like the fuel gauge and sender and I think a few other little things that did not work. That is probably a more severe problem since the battery is directly connected wrong, instead of just hooking up jumper cables backwards.

Just test each circuit that is behind a fuse and see if there is power there or not and work your way through the system. Like you said, the headlights work, so probably everything off that circuit is fine (likely the headlights were off when the jump start happened). Then make a list of all the circuits that don't work and try and find a common point (or two) where those circuits get power from and that is where the problem likely is.

blakefogt

I'm working on a lexus that someone did the same thing to right now. once you check every single fuse (it can take out many) check the igniter, its not common but I have seen it.

dropzone

iTrader: (6)

Why is it still like that?

Robsteeler66

Sweet! I checked the 80amp fuse and it was blown. I picked up a new one and it cranks right over now. woot woot! The only problem now is it sat for so long that I think the gas is bad now I hope I don't have to drain the tank. I hate working on this truck without a tetanus shot! Thank you all for the help. Oh, and my dummy was trying to impress a girl from school who walked home with him. He's 15. Lol! Kids will be kids and boys will be boys.