M1009 Electrical Disaster while changing belts

[Stratoghost]

A couple weekends ago, I went to Autozone to get some new belts. The belt on the drivers side alt went on fine, but the one on the passengers side was a little tight. I pushed the alternator so that it would slide down the adjustment bracket some more and the positive input terminal came in contact with the bracket (the rubber cover had deteriorated). It immediately welded itself to the bracket and it took several frantic seconds for me to pry it loose. By then I had noticed blue smoke coming from where the alternator had touched the bracket and near my glow plug relay.

I am ok when it comes to working on engines, but when it comes to electrical systems I am not so competent.

When I turn the key, nothing happens. Nothing at all works except for the cig lighter outlet that I directly wired from the battery. The horn doesn't even work.

Here is what I have done so far:

Tested the batteries. Both are new and still good.
Checked all the fuses in the fuse box.
I replaced the glow plug relay.
Found a fusible link that was blown out below the glow plug relay and replaced that and the one next to it.
Replaced the fusible link going to the resistor ? board behind the air filter.
Came here and read a bunch of stuff.
Replaced the ignition switch.
Replaced the starter relay.
Tested the glow plug relay like the CUCV wiki suggested. It goes clunk when it should.

The CUCV wiki stated that if the glow plug relay works but does not work when turning the ignition that the controller board is bad. However, nothing at all works. I would download the wiring diagrams for this thing and attempt to decipher them, if they were available. I think the links may be broken.

There must be some big fuse somewhere that I am missing, or the controller board connects everything to the batteries.

Any help would be greatly appreciated.

 

[erniemigi]

we had a similar problem with the one i got just recently, what we did was just took out the the bad controller card and hooked up a switch and a relay and it fires up everytime, its" pretty simple and a quick fix instead of trying to find a new controller card, i have the whole manual send me your e-mail and i will send it to you

 

[Napoleon_Tanerite]

are you sure the batteries are good? your truck sounds like it's doing the exact same thing mine was doing when i shorted out the front battery. i know you said they're new, but they could have shorted out.

 

[johnsr]

are you geting any vlotage to the cab/fuse box? i would look at the fusable link coming off your battery going to the rest of the 12v system. it is right next to the master cylinder, big red wire. outher than that check all you fusable link, i just replaced mine for the gen 2 wire and it looked fine but fell apart when i touched it.

 

[lindyp38]

we had a similar problem with the one i got just recently, what we did was just took out the the bad controller card and hooked up a switch and a relay and it fires up everytime, its" pretty simple and a quick fix instead of trying to find a new controller card, i have the whole manual send me your e-mail and i will send it to you

can u post a pic of what that set up looks like...?

Thanks

 

[erniemigi]

here is the pixs of it, on the switch we ran a blue wire to the fuse box and a white to the relay, now from the relay we ran 2 wires to the grounding post that is located on the side wall under the dash, and the red wire we ran to controll board wire harness, there we used quick connects to attach to the two blue wires and a pig tail, now this is not a toggle switch we used, not advisable to use 1 of those, what we used is the type that you push and hold and when you let go the switch turns off

 

[Stratoghost]

Batteries are good. I did not know there was another fusible link next to the master cylinder. I replaced two that were somewhat near it. One was blown out. I'll check again in the morning.

 

[mistaken1]

The wiring diagrams are available, I believe they are included with the TMs that can be downloaded. Look at the link resources link at the top of the page.

Nothing at all works except for the cig lighter outlet that I directly wired from the battery.

Somewhat off topic, what size fuse did you use between the outlet and the battery?

 

[johnsr]

yea ther is a little black box on the fire wall with 2 nut. there should be like 7 wires coming from it. one from the batterys, your gen1 positive that loops back around to gen2, and a few more. its right above you driverside vale cover next to the master.

 

[Warthog]

You have indeed blown the fusable link that supplies 12v to the entire system

Looking at the wiring diagram the wire is labeled 2A. It runs from the negative post of the rear battery to the 12v Postive Terminal Block that is next to the Glow Plug Relay. It is Diamond shaped.

Fusable links are not as easy to replace as a fuse is, but it just saved your truck from a major wiring meltdown.


Right click on the thumbnail and choose "Open Link in New Window"

 

[Stratoghost]

Mistaken1, the links to the TMs that can be downloaded are broken. I cannot download them.

I wired in a secondary aftermarket fuse box and put 10 amp fuses in it as all I was going to use the outlets for was a fan and cell phone charger.

JOHNSR, Thanks a lot! I had already replaced 2 (one which was blown) but since you mentioned one on a red wire coming from the battery, I had to recheck it. It ran flush underneath the part you described and I did not see that it had a fusible link. When I went to examine it, it fell apart.

I just replaced it and my truck started right up!

 

[Stratoghost]

Thanks Warhog for the warning. I wired it straight up just to see if it would work. I will now go back and put on a fuse.

 

[Stratoghost]

I got to Autozone with the destroyed fusible link and they nor I have any idea how many amps it was rated for. They have no resources for looking up stuff like that. I brought up the wiring diagram on my phone, but they still had no clue.

Does anyone know what it is supposed to be?

 

[Warthog]

It appears the old server that has the Tech Manuals is down. With the GA ralley, there are alot of people out of pocket.

Looking at the diagram, the RED wire for the 12v feed circuit is Wire Size 8 which is a 8 gauge wire. The BLUE fusable link is wire size 3 which is a 12 gauge fusable link.

When the servver comes back online, download the manuals, read the first few pages of the Troubleshooting section of the TM 9-2320-289-20 or TM 9-2320-289-34 manuals to see how the wiring diagrams are labeled and then look in Appendix F or Appendix E.

 

[cjtroutt]

Warthog Keep up the good work thank you tech support N cucv.
84 M1009
86 M1008A1
86 M1028A3 Cummins
71 M35A2
71 M818
94 M916A1

 

[Brutusdog]

So, if I am going to change my belts, how can this accident be prevented? Just unhook the batteries before starting, right?!

 

[Crash_AF]

Drop me a line in response to the email I sent you and I'll email you the TMs.

Later,
Joe

 

[Stratoghost]

Brutusdog, since I didn't have a replacement for the rubber cover, I took a piece of 3/8 tubing, sliced it longways and taped it to the wire so that it covered the post. It is sitting mostly under the adjustment bracket, so it isn't an eyesore.

 

[Warthog]

So, if I am going to change my belts, how can this accident be prevented? Just unhook the batteries before starting, right?!

You should always disconnect the batteries when messing with alternators.

When the trucks came from the factory they had a rubber boot protecting the wires. Over time, age and heat took most of the rubber boots out of action.

Use your imagination to find something "new" to replace them. Rubber hoses, new boots (if you can find them), etc.

 

[rnd-motorsports]

sometimes that one extre step unhooking the batterys can save a lot of extra step's fixing an oh!! $$$$