weird electrical issue

[Bob89manche]

I’ve worked my way through this list and am still hitting a wall. 89 mj 4.0 6cyl auto. Problem started as “car keeps running after key is removed and lock cylinder switched to “”off”” position”. Upon further inspection, everything gets power when the battery is connected except for radio, accessory, and cab lights. Replaced ignition switch,coil,ICM, starter relay, o2 relay, fuel pump relay, latch relay,ballast resistor, battery + and - cables, all duct tape covered splices cleaned and properly wrapped, all connectors cleaned, c101 cleaned, grounds cleaned and/or replaced. If I disconnect, from the battery post of the starter relay, the loop connector with green fuse link to 3 red wires and/or  the loop connector with both green and orange fuse link to individual corresponding red wires, power does not reach the previously affected systems. If all relays removed, ignition switch disconnected, oil and battery lights in instrument cluster still illuminate. I’ve searched for broken wires, burned tape/ connectors. If you remove the ECU the dash batt and oil lights still illuminate. Color me stumped. 

 

Idk if this forum is still used, but fingers crossed someone can help shine some light on this poor lost soul. The truck only has 140kmiles. 

 

Thanks All,

        Bob 

[Pete M]

On 12/15/2019 at 7:53 PM, Bob89manche said:

I’ve worked my way through this list and am still hitting a wall. 89 mj 4.0 6cyl auto. Problem started as “car keeps running after key is removed and lock cylinder switched to “”off”” position”. Upon further inspection, everything gets power when the battery is connected except for radio, accessory, and cab lights. Replaced ignition switch,coil,ICM, starter relay, o2 relay, fuel pump relay, latch relay,ballast resistor, battery + and - cables, all duct tape covered splices cleaned and properly wrapped, all connectors cleaned, c101 cleaned, grounds cleaned and/or replaced. If I disconnect, from the battery post of the starter relay, the loop connector with green fuse link to 3 red wires and/or  the loop connector with both green and orange fuse link to individual corresponding red wires, power does not reach the previously affected systems. If all relays removed, ignition switch disconnected, oil and battery lights in instrument cluster still illuminate. I’ve searched for broken wires, burned tape/ connectors. If you remove the ECU the dash batt and oil lights still illuminate. Color me stumped. 

 

Idk if this forum is still used, but fingers crossed someone can help shine some light on this poor lost soul. The truck only has 140kmiles. 

 

Thanks All,

        Bob 

 

 

I'll move your question over to the Tech forum.  

[cruiser54]

Did you adjust the ignition switch properly down on the column?

 

Did you know the switches are different for tilt vs non-tilt wheel?

 

 

[Bob89manche]

So I’ve gotten a little further with this after the holidays. I have found a conglomeration of Black ground wires connected together right by the MAP sensor similar to the yellow wires that give power to the ignition system. I have found a completely bare wire (looks like throttle cable) soldered to the ground connection leading to TBD. I have stopped cutting hot wires to the system and started cutting grounds. Definitely power bleeding into the ground system of wires. Can’t find a good engine harness replacement. Going to search junkyards and trace this bare ground wire to see if it yields any results. Thanks for all the help, guys

[MiNi Beast]

Have you checked headlamp switch by chance? Also anything with combination switch on column? And look again at what you started with.