Can a multi meter be used to check each section ,how would i do that...multi meter is a recent purchase so still figuring out how you use them.have had the dash out today for visual check ,stripped back cable tape,nothing obvious,changed ignition switch ,have done away with switch connector,soldered heatshrink eliminating possible issue.Will check bulk head connection again tomorrow.will keep you posted,Thanks
Go down to Radio Shack and get a couple of packages of various size clip leads, and look through their parts drawers and buy a couple of packs of alligator clips. That way you make up some Looooooonnnnggg clip leads to extend yours if necessary.
You need to put a "load" on the circuit on which you are trying to find the drop, because with no load, there is no drop. That is, the meter does not add enough load of it's own to provide any drop, and show the problem
Since you may have the key on for extended periods, it might be wise to pull the regulator IGN lead off, just pull off the connector.
Likewise, pull the connector off your igntion box.
To "load" the system, get something like a spare stop/ tail lamp, or even a headlamp. "Clip" this temporary lamp onto your ignition supply lead out in the engine bay. You can clip onto the blue field lead on the alternator, or the IGN terminal of the regulator, or the "key" side of the IGN ballast resistor.
In other words, you want the key "run" power on the IGN "dark blue" coming out into the engine bay feeding this temporary load.
Now there are two ways to measure this, but the one which shows up the easiest is to measure "voltage drop" along the harness as you go.
So with your new-- found clip leads, clip one lead onto the battery positive terminal, or as close as you can get, such as the "big stud" on the start relay.
Hook this lead to one side of your meter, and tape it up if necessary so you don't short the thing to ground.
Now you can take your other meter lead and probe various points to check "the drop."
To see, FIRST, what you are working with, put your probe on the hot side of your temporary load. You should be measuring some drop, you mentioned 1.5 volts. The amount of the load will change this, but whatever you have with the "test load" remember it, as you should get "less and less" as you work your way back to the battery
Now probe BOTH sides of the bulkhead connector on the dark blue IGN lead, and see if this reading changes. That will show a problem in that connector.
If you can reach, without shorting something (or unhook the battery temporarily) reach up in the dash, and hook a clip onto one side of the ammeter. Bring the clip down for access, and check there with your probe.
Remove the trim under the column so you can get to the column connector, l get your diagram, and identify the correct wire coming out of the IGN switch, which for many years is still DARK BLUE
Probe that and see what you have
You need to probe the "hot" feed into the switch coming from the ammeter circuit. This will be a LARGE wire, and I just realized I'm not sure what year/ model you are working on. Refer to your diagram, the feed from the AMMETER circuit to the IGNITION SWITCH and that is the one you want.
By reading these voltage drops, you should be able to identify the origination.
ALSO by working the bulkhead connector as well as the ignition switch connector in/ out several times, may "scrub" the terminals clean and that will of course show you that you're in the right area