System Shorting Out HELP

[DieselDunn]

My electrical system is shorting out somewhere in my truck. A crackling is over the speakers and my speedo is going whacky when the stereo crackles.



Somebody told me that the wires chaff at the base of the steering column and that is what is shorting out.



Do you think it could be a bad ground?



Have you ever heard of a whole fuse box going bad? It seems to dim my lights when I hit the fuse box under the hood.



HELP

 

[Alan Reagan]

If the lights dim when you hit the fuse box under the hood, start looking for chaffing on the harness that runs from the box. And yes an entire fuse box can go bad. I had it happen on an Audi several years back and had to jumper around several connections to make to fuel pump relay work until I could get a new one for the replacement.



If you have an ohm meter, you should be able to disconnect the batteries and put use one lead to check the hot side of the fuse in the box under the hood and the other lead to ground. Set the meter to the Kohm range. It should read infinite resistance. Bump the box. If the needle moves toward zero, you are shorting somewhere. I had this happen on a chevy diesel. The short was in the glow plug harness. Before I could find it, I had the entire harness burn up at the firewall. You don't wan't to go down that road. The symptom was that the fuel gauge fuse kept blowing. It had the glow plugs on that circuit. I can't believe you aren't blowing a fuse somewhere.

 

[DennyDay]

Short

Sounds a lot like a loose connection or corrosion on a connector.

Start with the battery cables, remove and clean, then the fastners in the main breaker box, then to plugs and fusable links looking for something loose. Also wiggle harness plugs and look for signs of heat - - discolored wires and plastic connectors. Start under hood, and then under dash. The static and intermitent speedo failure indicates to me something is loose, or main wire is pinched.

Denny

 

[DieselDunn]

Found the culprit. It was under the hood on the drivers wheel well. You'll have to forgive me but i'm going to try and describe the problem.



There is a line running from the brake housing down to the bottom of the engine. In line with that line is a filter housing of some sort.



While I was driving this filter housing was banging against what looked to me like some sort of grounding housing.



The housing has three what seems to be negative terminals feeding into it. It is attached to the drivers side wheel well. It then has four small gauge wires coming out of the top. Well the filter housing was banging against those four wires causing them to short out.



I know this explanation sucks, but on further examinatiion I looked at that block on the wheel well which looks very corroded and looks like it needs to be changed. The wires which are plug in are very loose also.



Does somebody have a mx manual that can give me a part number and explain to me what this piece is.



I zip tield the filter housing to the air intake to keep it from knocking against the grounding housing.



Thanks for all your info, it turns out I was looking in all the wrong places till i checked this forum.

 

[DennyDay]

Loose

Is it the engine heater relays. From your description and location it's the problem.

Denny