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bad jump start

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WillR

WillR

Jedi Warrior
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Doc, pop word problem of the day, :devilgrin: so a well intended man helped jump my B. ( i left my lights on while working a double :wall:) i set my side up and let him do his. They went on backwards. we fixed it, just not fast enough. as soon as my ignition turns on my started cranks and will not shut off. my guess is fussed ignition and starter wires. did i do more damage? anything im missing?
 
Starter solenoid went bad maybe.
 
It will let juice go to the starter? Crazy but i wouldnt doubt it.
 
What year is it Will? If it's a '75~'76 or newer there's a diode in the seatbelt warning circuit, likely that took a "hit".

If ya don't have it, go to Advance Auto Wire and download the wiring diagram, start chasin' electrons. It ~could~ be the solenoid but my money's on a white wire/red tracer issue. That's the wiring connecting the diode and seatbelt nonsense to the ignition circuit.
 
its a 78 doc. i now carry a blue print size print out of the diagram in the map pocket. :smile: when i had my seats out this summer i saw a loose wire under my seat. so i should follow it to it connection and look kfor some burnt wires?
 
It tangles all thru the thing. Switch at the handbrake, power from a "smart box" hidden behind the center console up front, starter relay... you'll need to check along the circuit. I'd start with the relay. Heck, it may be that the relay is bad.

The only things I can think of which would be current polarity sensitive are that diode, the control box for the belt warning circuit and your tach. Oh, and the fuel pump if it's an electronic one.

You can look for fried wiring but a test light and th' map would be my method. Disconnect the wire from the relay to the solenoid and start chasin'.
 
I just looked at the schematic. Yours apparently also has a diode at the "service interval counter", too... bah. Unless you want it to be "all original" I'd be for isolating all the warning stuff and have the relay trigger from the iggy switch to the relay as the ONLY thing connected.
 
im all for making it a simple daily very reliable driver. simple is good. its fine to unplug all the other stuff? i say lets do it. i work today so tomorrow i will start looking for things to pull. Thanks doc. p.s. i like the new pic
 
heh. good.

Th' "new" pic is really th' "old" pic. I may change it to somethin' else entirely soon.
 
WillR said:
im all for making it a simple daily very reliable driver. simple is good. its fine to unplug all the other stuff? i say lets do it. i work today so tomorrow i will start looking for things to pull. Thanks doc. p.s. i like the new pic
Click to expand...

I just unplugged all the diodes on mine and removed them. for some reason when I plugged in the brake failure switch, my starter wouldn't stop. On mine (Midget) the diodes were all three under the dash above the glovebox

BTW Doc, as part of the process, I also cut one of the red/ white wires - didn't affect starting but, might that be why the seat belt switches don't work?
 
The solinoid should have a positive lead from the battery going to the solinoid and the brown wires I think attached there with it. And then the other large wire goes to the starter. If you run a jumper accross these two wires the starter should engage unless it has gone bad. The other two smaller wires should have one that is on positive when the ignition is on only and the other will be positive only when the key is turned to start. It sounds like the solinoid is stuck in the start position to me from how you described it. Your local auto parts store should have several generic solinoids that can be fitted to work and they are not expensive.
 
JPSmit said:
BTW Doc, as part of the process, I also cut one of the red/ white wires - didn't affect starting but, might that be why the seat belt switches don't work?
Click to expand...

Most likely. But ya gotta be cautious... <span style="font-weight: bold">ONE</span> of those white/red wires energises the starter relay. From the "start" position of the iggy switch. :shocked:

The green wire(s) at the brake switch fed back thru the diode and activated the starter relay with constant V+. That's what I've found in nearly 100% of all the "constant starter engagement" cases.
 
DrEntropy said:
JPSmit said:
BTW Doc, as part of the process, I also cut one of the red/ white wires - didn't affect starting but, might that be why the seat belt switches don't work?
Click to expand...

Most likely. But ya gotta be cautious... <span style="font-weight: bold">ONE</span> of those white/red wires energises the starter relay. From the "start" position of the iggy switch. :shocked:

The green wire(s) at the brake switch fed back thru the diode and activated the starter relay with constant V+. That's what I've found in nearly 100% of all the "constant starter engagement" cases.
Click to expand...

exactly what I had - and I cut the OTHER wire :banana:
 
I just put a new soliniod in a few weeks back to solve another problem i kept it to i will just use the old one to test if thats the problem. i still want to strip all the unnecessary crap out. i have my battery out on a trickle charger and driving a "modern" car. power steering, enclosed cabins, warm feet??? what is this crap!? :crazyeyes:
 
i put two new relays in and it seemed to solve the problem.. i tested the charging system. 12.5 at the alt and 12.4 at the battery. it drove fine for about 100 miles. then it just would not start. battery died. it ran home with a jump but it was rough on the highway. it would seem to hit a wall and loose power then get it again then loose it. i must have a drain somewhere. would low power cause it to shutter like that?
 
You should see in excess of 13V with the engine running, meter at the battery terminals. With an alternator it would be 14+V. Sounds like the alternator has packed it in.
 
yeah... what he said :smile:
 
would there be a diff with a generator? i have whatever came stock with the car.
 
<div class="ubbcode-block"><div class="ubbcode-header">Quote:]Unless you want it to be "all original" I'd be for isolating all the warning stuff and have the relay trigger from the iggy switch to the relay as the ONLY thing connected.[/QUOTE]

that would unplug inertia switch
anti run-on valve
dreaded seatbelt module
headlight switch(???)
and the radio that was pulled by po
all this is ok?
:sleep:
 
ok it looks like keep the white red wire an unplug everything else. it will be a few days before i get to that. we will see. im thinking of putting the harness from advanceautowireing.com in. that sounds like it will simplify the system and make it more reliable. thats what im looking for. plus\ by the time im done i will understand it a bit more. :smile:
 
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