Intermittent no crank no start...running low on ideas

[awg]

do other electrical systems die, such as lights?

If so, suspect the main battery cables and connectors

I agree it could also be NSS or ignition switch

[Roler]

Originally Posted by alexbrown64

Hey Roler,

Seems like your pulling your hair out and have tested everything.
To me, it still screams of the NSS. I know its only 5 years old, but just to totally eliminate it being an intermittent problem, why don't you try this 5 minute free mod and run it for a week.

https://www.youtube.com/watch?v=UqCvJ4IWNQI

If its not that, could it be an intermittent problem in the computer?

Cheers,

It crossed my mind of course, but I understand that the NSS provides a ground at socket for pin 86 and therefore should read 12Volts which I have. I have the YouTube link on my laptop, not here unfortunately.

The pcm is my biggest worry...

[Roler]

Originally Posted by Classic Boy

There are a number of contacts in the starter switch on modern engine management that do a number of things simultaneously such supply power in the start position one for the starter relay others are to send the start command to the ECU and other modules, having a poor contact on the other contacts can cause a no start.

Judging by the number of wires on the connector, I think you're absolutely right. But how to check all the others?
The NSS would be Nr 1 to check I reckon, and how come I have power on socket for pin 30? Or maybe that's hot all the time and sending me in the woods...because I can make it run by jumping 30 to 78....

[rainman]

my experience is with a 95.

pin 30 on the start relay is always hot.

in the 95 the nss switches the relay and the pcm to earth. it does not connect the relay to the pcm for the pcm to earth the relay.

the nss grounds to the Dipstick stud.

u stated that when you turn the key to start, start relay the relay clicks, does it click every time or is the starterrelay not clicking the intermittent problem?

[Roler]

Clicks every time during the no crank no starts

[rainman]

if its clicking every time, and u tested pin 36 for 12v+ve and the relay is good, then the problem is between the relay and the starter solenoid. NSS, and pcm are all good/ upstream of the problem.

mate check the small wire that goes to the starter, specifically the" integrated" plug that combines the big wire from the battery and the small wire terminals to the solenoid.

you are looking for 12v+ at the small wire that goes to the starter solenoid every time u key to crank.

good luck with it.

[awg]

Originally Posted by rainman

if its clicking every time, and u tested pin 36 for 12v+ve and the relay is good, then the problem is between the relay and the starter solenoid. NSS, and pcm are all good/ upstream of the problem.

mate check the small wire that goes to the starter, specifically the" integrated" plug that combines the big wire from the battery and the small wire terminals to the solenoid.

you are looking for 12v+ at the small wire that goes to the starter solenoid every time u key to crank.

good luck with it.

Good post,, and leads to what I had a couple of times, and took a little time to diagnose too

A failing starter solenoid..the internal points burn and wont always pass full current

In this instance, the damm thing will pass any test, but fail under load

all you get is a click at the relay..but if there is 12V at the solenoid terminal, that will be the problem

even though you can get a replacement solenoid, the most realistic fix is replace starter

if the problem is intermittent, run a test light into the cabin