ENGINE CONTROL FUSE BLOWING #17 20a

[Chevybrit]

Hi Guys
Really pushed for time so apologies for repeating what might already be out there..
I have/will continue searching posted threads in the meantime but just in case someone has had the same exact issue
and can save me some extra work...

My M1009 has and is my daily driver and i've been putting on some proper miles in it.. recently the wait/WIF lights stopped coming on at start up but the volt etc all worked and the truck had been running ok.
Last weekend I went to work on the blower as it had blown the fuse a few months back and its starting to get chilly so i cleaned up some contacts to the motor ... connected power direct and it seemed to be running ok.
I pryed out the melted fuse and replaced it and tested the blower for some time and all seemed ok.

(the above may or may not be relevant so I thought id include it)

My main issue now is the alt has stopped charging and i needed to sort this quick. It has had the 12v conversion as the batteries are in parallel and the alt 2 Passenger is the only one present.

Whilst looking through the fuse board I noticed #17 (20a) engine control fuse had blown .. Aha I thought Praise God maybe a quick fix
but as soon as the ignition is turned on it blows again ...

Please point me in the right direction and apologies for possibly a lot of unnecessary info

 

[cucvrus]

Check temp sensor on right rear head. Could be melted and shorted out.

 

[Chevybrit]

Thanks am currently going through this thread

https://www.steelsoldiers.com/showthread.php?57380-Engine-Control-Fuse-Help

 

[Chevybrit]

Ok for some reason PO has bypassed it





The wire looks brown but i think it must be the pink / blk
obviously i'll check just to make sure there's continuity and its not totally rotten inside the screw cap ...
(there is another temp gauge as i have an operating aftermarket one working in the dash

 

[Tinstar]

The sensor bypassed/not connected is for the Hi-idle solenoid.

No clue on rest since system has been modified.

 

[Chevybrit]

Ok the gen 2 plug reads

Ign off

12.8 red wire
.51 brown

Ign On

12.8 red
8.9 brown

 

[Chevybrit]

The sensor bypassed/not connected is for the Hi-idle solenoid.

No clue on rest since system has been modified.

Hey Tinstar
Thanks for the comment, can you clarify then that the picture is not the temp sensor but the Hi idle solenoid ? Or are you saying the wiring is for the Hi idle solenoid ?

 

[cucvrus]

That sensor you have shown on the right rear head is the high idle sensor. It can blow that fuse. I don't know how it will react when it is bypassed. I never bypassed any.

 

[Chevybrit]

Is the temp sensor there somewhere too?

 

[Chevybrit]

I cleaned up the alternator plug and checked readings whilst the truck was running ... its showing 14.7v so the alternator is working.
I also removed the firewall side of the fuse block and give it a going at with a thin wire brush attachment on a small cordless... some brake cleaner and
the air line .... (What the dickens is that black stuff?? lol)
After replacing the #17 fuse it didn't blow and I got the check seatbelt light... (which i've not seen before) and the wait light for a brief moment.
It is also charging again : )
I would like to progress a little more and sort out why the wait light is not on for long enough and the WIF light .. my hunch is it could all be related to the blower fuse meltedness..

 

[Tinstar]

Hey Tinstar
Thanks for the comment, can you clarify then that the picture is not the temp sensor but the Hi idle solenoid ? Or are you saying the wiring is for the Hi idle solenoid ?

Engine temp sensor is drivers side head at the front.
Glow Plug temp sensor is drivers side on top of block by firewall.
The sensor you took pic of, as already stated, is the High-Idle temp sensor for the solenoid on top of the IP.
No idea what the wiring is in the other pic.

Since your truck has been modified, I am no help since I haven’t a clue what’s been done.

 

[Chevybrit]

You've been a help, thank you .. I'm looking to buy a M1008 which hopefully I'll find one that has not been molested ... till then I'll steel soldier on to straighten out the M1009

 

[Tinstar]

Your discovering why most guys here recommend keeping truck stock. Wiring anyway.
That way you have the TMs to consult and a lot more help here.

The starting and charging system is a solid, proven design.
Maybe not the best as it could be, but it works very well.

 

[MarcusOReallyus]

.. my hunch is it could all be related to the blower fuse meltedness..

Fix known problems first. Otherwise you could be chasing your tail.

On another forum for a different vehicle, I made that suggestion to someone with a problem. 3/4 of the known universe jumped all over me and called every kind of stupid in the book, and a few new ones. "That could never cause the problem he's having, you idiot!"


Well, after chasing his tail listening to all the expert advice from the people who had forgotten more than I would ever learn, he finally got frustrated enough to fix the known issue.

All problems solved.

Fix known problems first. Just cuz.

 

[Chevybrit]

3/4 of the known universe ...................FUNNY Makes me think of the bar scene in StarWars VI ...."My friend doesn't like you........I don't like you either"

https://www.youtube.com/watch?v=yVKySA2-47c

 

[dependable]

the blower as it had blown the fuse a few months back and its starting to get chilly so i cleaned up some contacts to the motor ... connected power direct and it seemed to be running ok.
I pryed out the melted fuse and replaced it and tested the blower for some time and all seemed ok.

(the above may or may not be relevant so I thought id include it)

My main issue now is the alt has stopped charging

I agree to fix known problem first, however, since the #1 alt is excited by the same circuit as the blower motor, the above may be relevant.

If the wiring has been really hacked up on a CUCV, I find the easiest way to make it right is to replace the wiring harness with a stock one. They show up for sale on this forum, or check with a vendor who parts out trucks.

Replacing the harness is not much work compared to chasing down the "creative" work seen on some of these. Talk about chasing ones tail....

 

[cucvrus]

You've been a help, thank you .. I'm looking to buy a M1008 which hopefully I'll find one that has not been molested ... till then I'll steel soldier on to straighten out the M1009

I have an 1987 M1028 all stock good running pick up sitting in my yard waiting for a new owner. Ready to go. I have a lot of vehicles and don't use them so I am moving them along to new owners. I am at exit 90 of I 81 if you are interested. But I agree. If you cut the first wire the problems begin. I have the same trucks for over 20 years. I repair the issues that arise as they arise. I don't try and reinvent the vehicle and it's system. It seems to have worked well for over 30 years. The broken record still plays. Good Luck. I hope it all works out for you. If you want a nice M1028 / M1009 I can make that happen for you also. I even have a 100% stock running M1009 at a budget price.