yes to run but not start

 

Hhhmmm, shouldn't have had power at pin 86 then...... That's supplied from the ignition switch in the 'start' position...... and jumping pin 30 to pin 87 should have engaged the starter......

 

so what am I looking for? I apologize for not being well versed in electrical

 

I think there is more than one problem going on there.

If you jump pin 30 to 87, and the starter DOESN'T engage, you either have insufficient power at pin 30, or the wire from pin 87 to the starter is broke. Solve that first.

 

Multimeters are handy tools when troubleshooting an electrical system. Unfortunately, one thing where they mislead you is that even that they show voltage, that wire may still be bad. When you ad load to that given circuit, it will fail. Still the multimeter shows full voltage. That's why test light is as much useful as the multimeter.

Easy way to check that wire from pin 87 to starter is even connected, is to set multimeter to ohm reading, and connect probes to a battery negative and to a pin 87, like in picture:



That's from my Cummins Dodge, I did double check the reading from the Jeep, and got the same numbers.

Also, there shouldn't be any voltage in pins 85 and 87, or on the pin 86 like HeyYou already said.

Out of curiosity I was measuring what kind of ohm readings I get from nss-switch. Seems to me that I have some grounding issues, even though everything works. Key on run, I got this from P and N:



Odd thing is, I had to turn the key to start position before meter showed anything. Then I turned key off, and got this, which seems more accurate:


​​​

 

so I ran the wire from pin 30 to pin87 and it started right up with the key on run. am I looking for a bad ground? if so where do I start looking? thanks to everyone for helping im still very new to the DIY on my truck. Best way to learn right?
I also plugged the voltmeter from pin 30 to ground with it on run and the reading went from 11 to 9 in about 30 seconds... could this be my drain and could it be responsible?

 

Unplug your alternator and see what happens. Might be a bad diode. On my old XJ diode went bad and it sucked battery dry in no time. Oh yeah, also that ZJ which is waiting to get fixed, also killed diode with exact same result.

​​​​​But for the start issue, measure with ohm setting that you have ground on pin 85, and use test light to check the pin 86. There should not be any voltage when the key is in run position.
You did check that neutral safety switch connector is firmly connected at the transmission?

If there isn't ground, you can make temporaly fix by taking piece of wire, strip one end about 3/4" or so, and insert it into the pin 85, and instal relay. Then strip the other end and mount it to a negative battery terminal or some other convenient grounding spot.

 

For your next trick......

You need a test light, or volt meter. Verify you are getting power on pin 85 when the key is in the start position. If you have that, check and see if you have ground on pin 86. (I bet you don't.)

 

 

Need to find where the circuit breaks. Could be at the neutral safety switch.....