Intermittent starting issues

Start with a wiring diagram .

This!

Then, look first to the power and ground supplies to the starter, then and only then look at the starting/charging circuit. You can either start at the battery and work your way wire by wire to the starter, or you can start at the starter (LOL) and work your way to the battery.

Depending upon year of vehicle and condition of components, it could be simple like the relay or it could be the alarm unit is internally compromised through corrosion or similar. But, the only way to find it is wire by wire.

I spent eight hours sussing out an EMS issue on the Big Yellow Truck and ultimately, that's what it took to confirm the good circuits were good and to find the problem.
 

Jake1996D1

Well-known member
Mar 28, 2011
3,363
1
West Des Moines IA
Miles on truck?

Miles on starter?

It could well be ready to be replaced. If original, it's 20 years old.

In stock, IIRC, aout $150 shipped but I'll have to look when I get home this evening.


It very well could be but until I've figured out why I have no signal at starter I'm probably going to hold of. I'll try to jump the connection and let you know if it turns over.
 

fishEH

Well-known member
Jan 26, 2009
6,929
203
Lake Villa, IL
Mine occasionally won't start. I jiggle the shifter and then it will start. My '95 had an issue with this too and I bypassed the shift solenoid. Had to snag one of the wires from the alarm ECU and ground it IIRC.
I could be way off, my memory is a little fuzzy on it because I haven't done squat on it in a while.

Maybe it was the Neutral Safety Switch. Shit, I can't recall. :/
 

p m

Administrator
Staff member
Apr 19, 2004
15,640
865
58
La Jolla, CA
www.3rj.org
it just happened to me last night. The first thing I did was to fire up the laptop and check wiring diagram in Rave.
Then I found transmission interlock switch ... and saw gear lever in "N." Could have simply looked around.
 

p m

Administrator
Staff member
Apr 19, 2004
15,640
865
58
La Jolla, CA
www.3rj.org
I took a note of that, too. Something is still bizarre - when it happened, the a/c fans came on with the key in starter position AND heater fan on.
oh.. and the key is bent :)
 

discostew

Well-known member
Sep 14, 2010
7,735
1,026
Northern Illinois
I assume that's what he was talking about when he said no signal at starter . I was thinking he's done that test and came up with no battery voltage when key in crank position . .
 

best4x4

Well-known member
Mar 1, 2015
595
72
Beaumont, TX
Discodick is on another roll I see...

I say worn out starter, soleniod, or cable issue. Had a very similar situation with an 04 Jeep Grand Cherokee 4.7L V8 and it did the exact same thing every once in a while. Took the WJ to the lake and boom of coarse it wouldn't start. Bypassed the solenoid and got it running. Replaced the complete assembly and was shocked how much faster it turned over.
 

Jake1996D1

Well-known member
Mar 28, 2011
3,363
1
West Des Moines IA
I assume that's what he was talking about when he said no signal at starter . I was thinking he's done that test and came up with no battery voltage when key in crank position . .

Correct

Disconnect the smaller of the two wires, connect circuit tester, turn key to on, does the light illuminate?

No it does not, what generally causes that?

I also used to have the issue where my truck would only start in neutral sometimes. Tried that too, tried holding the key in the on position. Won't turn over for anything, but I bet when I try to trouble shoot it again it will haha