YJ Ignition problem

CAPTAIN CNC · #1 07-23-2010, 09:59 AM

Hey guys,
I had a brain fart the other day. I saw the wire coming off the coil that goes to the condenser was just hangin there. I thought someone had stripped the wire off and slipped it under the bolt holding the condenser on and it had just fatigued apart. Like a dumbass and in a hurry and not thinking about what i was doing i restripped the wire and bolted it down under the bolt again... thus GROUNDING a hot wire. I turned the key and poof. Melted the short wire from the top of the coil down to the condenser. Now i'm obviously terrible with electrical stuff but had i been thinking right even i woulda known not to tie that damn wire to ground. Anyway, i cut the wire off the way it was and went to start the jeep. It will start and run about 1-2 seconds and shuts down. Any idea what the hell i've fryed? I have a spare distributor and computer and coil. I swapped each one thinking that would fix it but it still acts the same way. Can anyone tell me what happened when i grounded that wire and turned the key over? Or what may be damaged? I am really clueless where to start. Could i have ruined the alternator? It's the only thing i can think of that i haven't checked. Any way i can check if the alternator is bad or not with an ohmeter without the engine running? I need help.

entropy · #2 07-23-2010, 10:23 AM

Just Everybody Extra Parts.
You got the same ignition as my POS Ford

Yer Forked!
(jk)

In theory you should not have hurt anything cooking off that wire.
But on a Jeep, You could have fried who knows what...
I would test the Coil out for starters, then the Ignition box and Dizzy.
No real help but I understand the feeling

CAPTAIN CNC · #3 07-23-2010, 10:41 AM

That ignition module is about the only thing other than an alternator that i dont have a spare of. Could i "borrow" the ignition box off that 85 bronco i have just to see if thats it? Is there just 2 wires coming out of it? What does the "ignition module" do exactly? Can you explain why it will start with every turn of the key just fine only to die 2 soconds later.

transman731 · #4 07-23-2010, 11:00 AM

what year is this ? does it have security ?(theft light in dash)

CAPTAIN CNC · #5 07-23-2010, 11:05 AM

1989. Excellent notion. Thats exactly what its acting like. And YES it does have one in it but its never worked. How are those things wired into the system? Can i just unhook everything to it, or bypass it by jumpering 2 wires or something? It doesnt have power to it. Never has had. The inline fuse housing going to it is busted. Whatcha thinkin?

entropy · #6 07-23-2010, 11:34 AM

Quote:

Originally Posted by CAPTAIN CNC

That ignition module is about the only thing other than an alternator that i dont have a spare of. Could i "borrow" the ignition box off that 85 bronco i have just to see if thats it? Is there just 2 wires coming out of it? What does the "ignition module" do exactly? Can you explain why it will start with every turn of the key just fine only to die 2 soconds later.

Take a jumper wire and go directly from the battery to the+12VDC side of the coil and start it.
IF it runs after the key is in the run position you have a short on the Run wire between the ignition switch and the coil. There should be a resister in that wire run, and you may have simply cooked the resister.

I don't think that you have the Ford box I was joking...
BUT with a jeep, nothing would surprise me

CAPTAIN CNC · #7 07-23-2010, 11:37 AM

Gotcha. Thanks E. Gonna try that as soon as i pull in the driveway this afternoon.

CAPTAIN CNC · #8 07-23-2010, 12:24 PM

Is the resistor you speak of known as a "ballast resistor"? Located on the driverside firewall? White ceramic appearance?

entropy · #9 07-23-2010, 01:26 PM

Quote:

Originally Posted by CAPTAIN CNC

Is the resistor you speak of known as a "ballast resistor"? Located on the driverside firewall? White ceramic appearance?

Could be if they still use that type

CAPTAIN CNC · #10 07-23-2010, 02:01 PM

Quote:

Originally Posted by entropy

Take a jumper wire and go directly from the battery to the+12VDC side of the coil and start it.

Wouldn't this be jumpering past the ignition module too? I dont even know what the ign mod does but if it turns out the resistor is good i need to be able to find out if the ign mod is bad. That damn thing is 65 bucks. If i can locate this resistor would i be better off to just jumper it there? Or can that not be done?

I'm tryin to learn here. Sorry if it seems im nitpickin. I just wanna be sure about what i'm doing before i do it. I already got myself into this position because of not knowing what im doing with electrical stuff. And thanks again for the advice. I've been at a standstill with the jeep for a week now trying to track down this problem. This is the best lead i've had yet. This and the theft device idear from transman... thanks guys.

transman731 · #11 07-23-2010, 03:44 PM

if it has a factory theft deterent system, try unlocking and locking the doors with the key and then try to start it.
if you changed ecm's then the new ecm might have gone into theft mode when you hooked it up.

entropy · #12 07-23-2010, 03:46 PM

Quote:

Originally Posted by CAPTAIN CNC

Wouldn't this be jumpering past the ignition module too? I dont even know what the ign mod does but if it turns out the resistor is good i need to be able to find out if the ign mod is bad. That damn thing is 65 bucks. If i can locate this resistor would i be better off to just jumper it there? Or can that not be done?

I'm tryin to learn here. Sorry if it seems im nitpickin. I just wanna be sure about what i'm doing before i do it. I already got myself into this position because of not knowing what im doing with electrical stuff. And thanks again for the advice. I've been at a standstill with the jeep for a week now trying to track down this problem. This is the best lead i've had yet. This and the theft device idear from transman... thanks guys.

The Module triggers the coil but the power is not (usually) through the Mod.

CAPTAIN CNC · #13 07-23-2010, 04:37 PM

Jumpering from the battery to the coil and i get nothing. No spark. 12 volts is getting to the coil but not to the plugs. I'm unhooking the coil except to the distributor and connecting the jumper directly to the post on the coil from the positive battery terminal. Am i suppossed to leave the coils power wire and tach wire hooked up?

CAPTAIN CNC · #14 07-23-2010, 04:57 PM

If i leave the coil all hooked up and jumper to it the starter turns the engine over, it starts, then dies 2 seconds later.

If i hook an ohmeter to the pos side of the coil and turn the key to the run position i get 2.8V. If i then turn it to the start position the voltage jumps to 12V and the jeep starts. Then the voltage drops again, then nothing and the engine dies. WTF! Thats how its suppossed to operate no?

Will the jeep even start if the ign mod is bad? I have a new one due in tomorrow morning but the jeeps been nuttered to disable the stepper motors in the stock carb which it no longer has on it. I dont wanna cut those wires on the new ign mod if there's a chance the old one is fine.

CAPTAIN CNC · #15 07-23-2010, 05:01 PM

Quote:

Originally Posted by transman731

if it has a factory theft deterent system, try unlocking and locking the doors with the key and then try to start it.
if you changed ecm's then the new ecm might have gone into theft mode when you hooked it up.

The doors have never been hooked up since we've owned the jeep. Nor has the alarm system had power to it. Do you think it could have done anything to the ecm or anything else in the state it's in?

I'm really thinkin the ign module is bad but i dont know any way to confirm that other than hook up a new one and see if it works.

entropy · #16 07-23-2010, 06:33 PM

Quote:

Originally Posted by CAPTAIN CNC

Jumpering from the battery to the coil and i get nothing. No spark. 12 volts is getting to the coil but not to the plugs. I'm unhooking the coil except to the distributor and connecting the jumper directly to the post on the coil from the positive battery terminal. Am i suppossed to leave the coils power wire and tach wire hooked up?

You leave 100% of everything hooked up.
You then add a wire that goes from the battery to the power side of the coil.

CAPTAIN CNC · #17 07-23-2010, 06:38 PM

Thats what i did afterwards. And as soon as i touched the jumper wire to the coil post she started.... then died. If i kept the jumper wire in contact with the post on the coil the starter stayed engaged. Also, i could not find a resistor like i described ANYWHERE.

entropy · #18 07-23-2010, 07:00 PM

Quote:

Originally Posted by CAPTAIN CNC

Thats what i did afterwards. And as soon as i touched the jumper wire to the coil post she started.... then died. If i kept the jumper wire in contact with the post on the coil the starter stayed engaged. Also, i could not find a resistor like i described ANYWHERE.

I suspect the starter solenoid is FUBAR.
The jumper wire should have NOTHING to do with the starter, UNLESS something is FU...

CAPTAIN CNC · #19 07-23-2010, 07:24 PM

Awwww Fudge.... now im really stumped. I WAS anxious to get my hands on that new ign module in the morning and now ya got me REALLY doubting anything is wrong with it..............hmmmmm..........Well, i guess when you say "fubar" you mean beyond repair? Sooooo..... i guess i'll pull the starter in the morning before i head to town. I'll have em test the starter and solenoid on the bench and if it's bad i'll feel like you've found my problem E. If its still good.... well i dont know what to think then. My only other possible source would be the ignition module but it's gonna cost me 65 bones and i wont be able to return it if it's not the problem. I dont mind spending the dough if it fixes my problem but....

entropy · #20 07-23-2010, 07:32 PM

Going from memory...
There are three wires on the starter/solenoid.
Big Batt wire
2 smaller wires.
One small wire comes from the ignition switch.
One goes to the hot side of the coil.

IF that is true try disconnecting the small wire that goes to the coil.
Then apply the jumper Batt to coil, the starter solenoid and starter should do nothing unless the key is turned.
Reconnect the small wire that goes to the coil and then the jumper wire Batt to coil and if the starter fires up then something is wrong!