DFlintstone

I'd guess not many. 6 power injectors. About as many connect sensors to the ECU. The bears here are so hungry one apparently tried to eat the bark off one of my few Cedar trees...Killed it! (the tree)

zim

Minor victory. After checking into all the wire from the ignition switch to the fuse panel, then from the battery to the fuse panel connector and finding no problem signs. I put it all back together. Only two hots show up in that connection at the firewall by the way. I then put everything back together and started reading every thing I could about testing / jumping around relays. I ended up taking three wires and shoving them into the female connections of the wires to the relay for, fuel, ignition, and starter sol. Then pulled the ground wire loose from relay also and ran jumper to neg side of battery. I twisted all my three control wires together and touched them to the positive post. Jeep started and ran. I am now fairly sure it is the starter relay that has caused me this huge pita. Will be making the all day trip to a parts store in the morning. I realize that this was a rather simple crude test but it convinced me that the trouble is indeed the relay. Oh yes, the gauges worked while it was running. Any other things I should look for, or if my jump test is capable of false results, please say so.
Thank you all for sticking with me on this. I am actually learning about this auto electric workings a bit. zim

DFlintstone

OK...do watch for something intermittent, it did sound like the start relay was working, at least at one point...

1976gmc20

Where do you have to go - Roundup, Lewistown ???

zim

Think I'll hit Billings. Gonna go to parts stores, wally world and then hit a salvage yard or two and see what kind of xj goodies I can fish up while I am out and around.

1976gmc20

Oh, the Big City, huh?


O'Reilly's in Roundup: "We can have that in for you at 1:30 tomorrow"




Someday when I'm not sick maybe we could meet in Roundump for a cup of coffee

zim

I am beyond words on this one. Replaced starter relay, to no avail. Started pulling wires everywhere checking for kinks, back at square one. Jeep has been down for two weeks, I have worked on it for a few hours at a time for seven days and still am at the same place.
The only way it will start is when I jump hot to the three wires on the relay, (fuel, ign, starter) with a separate jump wire from the negative wire on the relay to ground. It then runs.
Anyone know how to bench test relays?

DFlintstone

I'm a bit toasted and still will be working till dark, (9pst). I knew it was not the start relay. Did you ever try the long wire off pos to the ign switch? "see what you learn with that" ?

Bummer....at least you found it's answerable!

mikeSDiego

Not the fat part of the wire , a fusible link is actually just regular wire but is 4 gauge's smaller than the wire it is protecting and thick insulation when they go they usually separate or you can pull on the wire and tell all the bad ones that I have seen showed some kind of burn through on the insulation.I've got the same thing with my Cherokee driveing me nuts, I have been going through all the wiring and had found corrosion on the back side of the fuse box and the wire connections . Couldn't believe the ignition switch would cause so much problems from draining the battery to loss of power . Still ongoing battle.

DFlintstone

Neat point Mike. If you pull on a failed wire the insulation will/can stretch, were metal won't. I think he maybe nailed/has that covered ????

zim

DFlintstone, yes I did pull a long hot to the ignition switch to no avail. (To red wire in ing. switch) Got the wife and full wiring diagram and going to sally forth once more today. If we can't come up with a fix, I will be installing tow bar on it and heading to a shop that specializes in wiring. I am thinking that I will start at the ign switch and run backwards to battery testing continuity on every wire as I go today. Wish I was cutting fenders instead!
Thanks everyone!

zim

Update. The boys talked me out of filling this thing with tannerite and shooting it to kingdom come, so I let is set for a few weeks to cool off. A friend found me a schematic of the ignition switch that I had not seen before. Low and behold, it showed a different wire going into the ign switch as "hot from battery" than what I had skinned out and tried jumping with long hot from battery. Skinned this new wire at ignition switch and sure enough, when I touched it to my "remote hot wire' everything works perfectly.
Ugh, I hate electrical problems, but am sure thankful that you can eventually stumble onto a fix if you keep asking questions. Now my question is, what is the best way of finding the break in the original wire now that I know which one it is. Posted is a drawing of my temporary fix.

DFlintstone

OK Here on post 55 weeks later.....

It's power is from one of the 5 or so fusible links off the big stud on the start relay. Don't think there are any fuses or relay between there and the Ign. switch. Not sure there, but pretty sure.

87-88, has the dreaded C-101 connector where the engine harness connects, but we still have that big plug on the firewall. so....


Please, what IS the color code on the wire you found that worked?

With that disconnected from the switch, try powering that up at the switch end. Any sound or spark connecting there? (check amps with meter). Do not give it enough juice to make a fire! If you juice it and it's shorted there could be trouble.

It's possible to ***** through insulation with a pin to check for voltage. Just sayen, to find where its dead, you have both ends.

There exists a nifty deal we use on house wiring. It's a little transmitter you clip on a wire. Then there is a reciever. You can then go around and listen for the signal from that transmitter from the wire it's pumping the signal into. Not supper spendy, if you work in the trades you might like having one.

I'd suspect that plug at the firewall myself...

zim

DFlnt, the wire color on the faulty wire is red, but there is another red and a red with white stripe also.
You refer above to the big plug on the fire wall. Are you speaking of the plug into the back of the fuse box or somewhere else?
The boys are driving it again but Staying close to home and not trusting the idea of a broken wire somewhere that may screw up again. I do not have a sounding tester but am thinking this evening that I will test continuity from the offending wire at ignition switch out to the connector side of each fusable link.
Thank you for sticking with me on this, it has been an unbelievable PITA to get hunted down. zim

DFlintstone

This shows a red to the switch from the green fusible link. This diagram is in my sig, says "thanks tom" ...On one of my 90's they are all red, and the other has more than one I might call green....

Truth is I don't know what is behind the harness connector. They don't all go through fuses, but is about there, removing the fuse-box should give access.

I might consider just running a new wire. Is one of your fusible links tagged Green? Maybe see that it's hot and connect there....(installing an inline fuse ups the chance it may blow and leave you without power at dome awkward time)