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98 Tahoe wiring


caw333
01-26-2011, 09:58 PM
1998 Tahoe 5.7lt 4x4. Been working on this thing for awhile and here is my latest findings. But first lets recap... bout 3 yrs ago I was running through some water down a high line and found a hole that was deeper than it looked. While waiting on a guy to pull me out the fan was sitting in water and slinging water on motor. I shorted some electrical sensors out. I changed all sensors, computer, fuel injectors,distributor well pretty much everything electrical under the hood. The thing still has a rough idle and some backfiring out the exhaust. Its slinging a P0339 and a P0341 code. Ok all that being said, tonight I was checking wires out and on the WHITE plug that connects to the computer I have 2 black and white wires that got hot and so I started checking continuity off of the ground wires that got hot to see if they might of melted to other wires in the wiring loom. Heres what I found just by probing by holding the black probe on one of the grounds I got continuity on wires 17, 18, 2 and 22. And 22 also shows continuity to 21, but 21 doesn't to the other three. Now with 17, 18, 2 and 22 you can randomly touch any one of the 4 and get continuity. So before I start ripping all the wiring out of there covers my question is does this sound normal for these 4 wires to have continuity with each other and does any one know what these wires go to. White comp plug wires # 17, 18, 2, and 22. oh also I can put my meter on 12 volts and put the black probe on any of the 4 wires and put the red probe on the + batt and get a 12 volt reading. "Electrical problems are the Devil:evillol:"

MT-2500
01-27-2011, 07:29 AM
1998 Tahoe 5.7lt 4x4. Been working on this thing for awhile and here is my latest findings. But first lets recap... bout 3 yrs ago I was running through some water down a high line and found a hole that was deeper than it looked. While waiting on a guy to pull me out the fan was sitting in water and slinging water on motor. I shorted some electrical sensors out. I changed all sensors, computer, fuel injectors,distributor well pretty much everything electrical under the hood. The thing still has a rough idle and some backfiring out the exhaust. Its slinging a P0339 and a P0341 code. Ok all that being said, tonight I was checking wires out and on the WHITE plug that connects to the computer I have 2 black and white wires that got hot and so I started checking continuity off of the ground wires that got hot to see if they might of melted to other wires in the wiring loom. Heres what I found just by probing by holding the black probe on one of the grounds I got continuity on wires 17, 18, 2 and 22. And 22 also shows continuity to 21, but 21 doesn't to the other three. Now with 17, 18, 2 and 22 you can randomly touch any one of the 4 and get continuity. So before I start ripping all the wiring out of there covers my question is does this sound normal for these 4 wires to have continuity with each other and does any one know what these wires go to. White comp plug wires # 17, 18, 2, and 22. oh also I can put my meter on 12 volts and put the black probe on any of the 4 wires and put the red probe on the + batt and get a 12 volt reading. "Electrical problems are the Devil:evillol:"

They are no sweat no problem with good repair info and a high end volt/ohm meter.
A good factory repair manual or a All Data DIY sub should lead you threw the problem.
They should have the pinout test and voltage reading you should have.

And remember you need a good high end volt/ohm meter to test voltage on computer systems.
Old analog volt/ohm meters will not cut the mustard.:rofl:

caw333
01-27-2011, 05:22 PM
Ok 1 more question... Should the Pink ignition wire that runs to pretty much every sensor under the hood be making continuity with any ground wire or negative terminal on a battery. Or when I probe the pink ignition wire on the ignition control mod with the ground on the same plug it makes continuity. I know all the grounds are pretty much tied into one another as well as the pink being tied together but it wouldn't make sense for the pink wires and the black wires to all be tied into one another.

MT-2500
01-27-2011, 05:45 PM
Ok 1 more question... Should the Pink ignition wire that runs to pretty much every sensor under the hood be making continuity with any ground wire or negative terminal on a battery. Or when I probe the pink ignition wire on the ignition control mod with the ground on the same plug it makes continuity. I know all the grounds are pretty much tied into one another as well as the pink being tied together but it wouldn't make sense for the pink wires and the black wires to all be tied into one another.

That is where you need good repair info with the wiring diagrams.
Pink wire to sensors is 12 volt power feed from ENG-1 fuse underhood fuse box.

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