Engine control fuse blowing.

[Jakelee93]

Hi guys first post here,

Im in the uk been rebuilding my m1009 for the last couple years, on the final stretch and this is causing me headaches. One day I went to start it and had no glows, found that the engine control fuse had blown, I replaced it and still no joy. Next I wired in a new switch to the earth terminal on the gp relay on the bulkhead/firewall and the other end direct to earth. Great it works, then when the truck is run for a few minutes the fuse then blows again This problem only occurred when the gp card stopped working and I wired in the switch so I can only assumed I’ve done something wrong. Has anyone else had a similar issue with this fuse?

 

[MarcusOReallyus]

Well, first of all, let's get something straight!

Welcome!

Now we need to get something else straight. What do you mean by, "engine control fuse"??? That term is not familiar to me.

Can you describe where it's located? What slot it's in?

As for the fuse blowing, I suggest you pull your GP controller card and see if something smoked there. Just pull the card and give it a look to see if there are any obvious signs of heat damage.


Sounds like your manual switch was wired correctly, so probably no worries there.

 

[cucvrus]

Check out the temperature sending unit on the right/passengers side rear head. It has 2 female spades in a pigtail connection. Has that become shorted from a loose connection and melted the sending unit and the plug. I had this happen a time or 2. Check that out and report back. I know there is a fuse slot marked engine control. Midway left side of fuse box. Am I correct? Have a Great Day.

 

[Jakelee93]

Check out the temperature sending unit on the right/passengers side rear head. It has 2 female spades in a pigtail connection. Has that become shorted from a loose connection and melted the sending unit and the plug. I had this happen a time or 2. Check that out and report back. I know there is a fuse slot marked engine control. Midway left side of fuse box. Am I correct? Have a Great Day.

Hey cucvrus, yes that is the fuse in question. Thought I’d sorted it butpopped again today while I was sat with it idling. Have checked that temp sender but will give it another check to be sure on good connections cheers

 

[cucvrus]

Check it closely. I would go as far as unplugging it and taking a good look at the pigtail for any tell tale sign of heat and also the temperature sender. I seen them melted slightly in the assembly. I mean these are old trucks and have seen a lot of wear on everything. At this point anything is possible. I am just sharing some of my experiences. Take Care and Good Luck. Report back. I appreciate all feed back positive and negative.