what are these wires for

[hughscpa]

I am still have problems with the bateries draining in the M1113. What would the "yellow" wires be for? Could that be the problem?

 

[nf6x]

Those wires with the yellow heat shrink appear to be connected to the 12V point between the batteries. Do you have the 4-speed 4L80E transmission? I don't have personal experience with them, but I seem to recall that their controller runs from the 12V tap in the HMMWVs. My HMMWV has the Hydramatic 400 3-speed transmission, and no loads connected to the 12V tap.

Anything in the electrical system might be the cause of batteries draining. The only way to find the problem is by measuring current draw or load resistance while disconnecting things one at a time to determine what's drawing current when the vehicle's off.

 

[hughscpa]

It does have the 4L80E. What TM has the wiring diagram on the M1113? I can't find it?

 

[hughscpa]

It seems to only drain on the 12 volt side.

 

[emmado22]

Dont they give you the manuals for this equipment when you pick it up? If not, shame on them for not doing so.

 

[nf6x]

It seems to only drain on the 12 volt side.

Excellent! You've narrowed down the problem to one of the 12V loads.

The M1113-specific manuals appear to be restricted on LOGSA, but I think you'll find info on 4L80E-equipped HMMWVs in the regular M998 manuals. If all else fails, it'll be a matter of physically tracing where the 12V power wires go, then figuring out what's drawing power when the truck is turned off.

 

[Augi]

There are wiring diagrams for the A2 models (which have the 4 speed) in the 280-20 TM appendix f. There are three connections to the 12v tap on the batteries.

The first is from the 12v tap on the alternator. This is to charge the lower battery as your TCM discharges it.

The second goes through the transmission power relay and feeds power to the controller and the tranny itself. The relay is switched by the ignition so you don't have power applied at all times and drain the battery.

The third connection bypasses the transmission relay and applies 12v directly from the batteries to the TCM. I don't know why it needs unswitched power though.

Augi

Edit: I took a look at the diagram and it is how I thought. Updated above accordingly.

 

[overlordofmars]

I had a drain on my MV, turned out to be a leaky diode on the alternator, sitting it would draw the batteries down after just a few days of not running the truck.

 

[hughscpa]

Thanks guys, I will keep you posted.

 

[Haasino]

I have 2 .pdf TMs that cover the M1113:

The old 1998 TM 9-2320-387-24P, which covers the M1113 & M1114, and the 2002 replacement version that covers the M1113 to the M1165.

I can send them to you if you know a way to email 20MB documents...

 

[hughscpa]

Can you test for a bad diode? I had to get another hmmwv today and use the slave cable on it.

 

[nf6x]

If it were my truck, I'd use a current meter to see if the alternator is drawing current when the truck's off. Then if I saw a drain, I'd pull it out and start checking components inside the regulator. But then, I'm an electrical engineer and have fancy tools, and explaining how to do it isn't so easy if you don't have an electronics background yet. Do you have any electronics geek friends nearby who could help you? There's nothing too tricky about chasing down an electrical drain, except it all seems like black magic until you learn how to herd electrons. It's just like plumbing, except you can't see the water unless the leak is really bad.

 

[hughscpa]

Is a current meter a multimeter? I am an accountant so I can do a tax return for the darn thing. Could I replace the voltage regulator if it is drawing a current? Are they expensive?

 

[nf6x]

LOL! I only know how to answer the first question: A multimeter can usually measure current, by disconnecting the circuit and connecting the meter in series. If you don't know what you're doing, you may blow the fuse in your meter... assuming it's not already blown. Fluke ( a high-end meter manufacturer) even made a line of meters that lacked the current measurement feature, specifically for electricians who kept blowing them up by using them wrong, as I learned from a Fluke sales representative I used to know. I have a (fancy, expensive) clamp-on AC/DC current probe for my (fancy, expensive) multimeter that doesn't have that weakness, but then I herd electrons for fun and profit.

Radio Shack makes a clamp-on meter that measures DC current, but I don't know if it'll reliably measure low enough currents to detect a leakage problem like yours. And they can be a little tricky to use when measuring small currents, since you need to understand how to zero them out properly. Much easier to show than to explain in text.

 

[nf6x]

Hey, see if this makes any sense:

Ammeter usage : BASIC CONCEPTS AND TEST EQUIPMENT

 

[Darwin T]

i am not sure how your system works, but if you are having a drain try one of these Priority Start. it won't fix the problem but it will keep it where your vehicle will start. when you hook up your load on the possitive side to the Priority Start when the battery gets donw to just enought power to start it disconnects the load to save the battery for starting. even if you leave your lights on.

 

[hughscpa]

Okay, I used the multimeter and put it between the front battery and the cable. -12.68 is my reading. I disconnected the wire on the front of my voltage regulator. Reading is 0.00. So is this my draw? Can I buy those as a seperate piece? I sure hope I have found this.

 

[nf6x]

That sure sounds like your draw. Was that amps or milliamps? Is there a tag on the wire with a circuit number? If you can tell me the number, I'll look it up on the schematic so I can understand exactly what you disconnected.

 

[hughscpa]

Dang it, I just took it back to the office. I can tell you it was the front, single wire held in place with a 1/2 inch nut. I can look at it tomorrow and give you the number. As far as amps or milliamps it registered on the multimeter when I had it on the 20M setting and the 200M setting not the 10 setting. Is that milliamps then?

 

[hughscpa]

It looks like the tag is "2". In the pictures it is the one that I have taken the boot off of. Thanks.