BJ70 electrical gremlins (1 Viewer)

[Jawsh]

Hey guys,
Last week my little Cruiser decided to strand me. Shortly before it died, I heard relay(s) clicking intermittently underneath my steering column/dash area.

A colleague managed to get me moving by hotwiring my fuel pump cutoff solenoid - not a long term solution, as the truck then cannot be turned off with the key. As best I can tell, the ignition signal is not doing anything. Starter still cranks at START position, and everything at ACC works as it should, but when I move key to IG nothing happens. No filter light, no glowplugs. This makes me think it's something to do with the ignition.

What's weird is that when I voltmeter the contacts on back of the ignition barrel, the IG position is behaving exactly as expected. 24V between IG and input (not sure what it stands for, but called AM in the schematics) when key is at ACC or LOCK, and close to 0V when key is at IG. Is there anything else that could be causing this issue? i.e. a relay in series with ignition signal?

Cheers
Josh

 

[Jawsh]

Update: Was going a bit insane, so went back to checking the basics, and my 15A engine fuse was blown. Doubtful this was the cause, more likely a symptom of the cause - but put a new one in, and my Cruiser started and ran no worries. Intermittent faults are probably my least favourite variety...

Bit irritating, because AA Roadside "checked" the fuses, and I spent a whole day issue-hunting working on the assumption the fuses were fine. Oh well, such is life.

Will update if truck continues to eat fuses. Fingers crossed it was just a random failure. Had this once or twice before on blade fuses.

 

[bj70bc]

Im not sure that this is a logical cause of what you are experiencing (and not knowing your year model truck)but have you investigated the fusible like ? may be worth looking into