Electrical Issues from a Newbie

[jdmdla]

Just got my first M1009. I have got several electrical problems going on. Nothing too major at first. I created more somehow trying to replace the blower motor for the heater. Somehow when I replaced the motor I blew the 20A fuse for the heater circuit as well as the 30A fuse in the head light circuit. I replaced both fuses and now, when I cut the fan switch on (truck warmed up) the generator 1 light comes on. After this as well, the generator 1 light, oil light, temp light and coolant does not come on when the ignition switch is forward. I am looking through the schematics but I am not seeing how it is all tied together.

On a side note, the hazard lights stop flashing when I press the brakes.

Any help would be greatly appreciated.02.0

 

[DonK]

Welcome to the wonderful world of the MV newb...If it Electrical, clean it. Rubber, replace it...
Figured i'd get that in first.
The Electrical system components do have a common factor, the Ground...Good luck

 

[mistaken1]

Somehow when I replaced the motor I blew the 20A fuse for the heater circuit as well as the 30A fuse in the head light circuit.

When doing electrical work on a vehicle always remove the ground terminal from the battery (or in our cases from all of the batteries).

Might want to check ALL of your grounds, especially the one under the dash on the drivers side (above the parking break). When grounds are broken, damaged or missing the electrons seek other paths to ground causing all kinds of weird issues.

Do a search for "ground" in the CUCV forum and you will find all kinds of strange things cured by good grounding.

 

[Barrman]

The flashers and the brake lights are the same bulb. All Chevy trucks of that body style have it so brakes take precident over flashers. Think about it from the view point of the person right on your bumper.

Follow the directions given above. Read, study and learn the -20 troubleshooting section and the wiring diagrams in the back of the -20. ALT 1 will glow in proportion to how high the fan is turning on a lot of these trucks. The rest of the lights should be coming on when you turn the key on. Pull the dash, clean everything and bench test each and every circuit on the gauge pod. These things are all dirty.

 

[txmytx_catahoula]

What Barrman said!

Before the computer driven vehicles, brake lights over-rode the Hazards( at least in all the vehicles I drove).

 

[soule64]

Good luck - I have a similar issue that I am trying to track down. Like the previous advice mentioned, it is probably a ground issue. Print off a schematic of the entire electrical system and check every stinking ground. Don't just wiggle them, unhook, clean and dab on some dielectric grease and then crank them down. Then do a continuity test between the lead and chassis. As for the schematics, I printed off all of them in color and bound them in plastic and leave them in the glovebox. Trust me, you're gonna need 'em...

 

[jdmdla]

When doing electrical work on a vehicle always remove the ground terminal from the battery (or in our cases from all of the batteries).

Might want to check ALL of your grounds, especially the one under the dash on the drivers side (above the parking break). When grounds are broken, damaged or missing the electrons seek other paths to ground causing all kinds of weird issues.

Do a search for "ground" in the CUCV forum and you will find all kinds of strange things cured by good grounding.

That is part of the problem. I did not remove the ground when working on the blower fan. What exactly does this do to the rest of the electrical system?

 

[mistaken1]

Short circuit current. Fuses are supposed to open to protect wires and components. Fusible links will also open to protect wires and components.

You could have open fuses, electrically check them and make they are making good contact in the holder.

The fusible links may look good but may be open. Physically examine them and electrically test them.

A corroded connection that is subject to short circuit current can go open or cause heat related damage at that point.

Also I would use electrically conductive grease on the grounds.

 

[jdmdla]

I would like to thank all of y'all for the help. After working on it most of the day. I would say that ever connector I took apart were corroded to some extent. I used a lot of contact cleaner, a lot of dielectric grease and several pieces of steel wool. I cleaned all the grounds near the fuse box. The black out light in the front was full of water as well. I am not sure exactly what fixed it, because I could not see the dash lights in the sun.

I got all of the dash lights working, including a low coolant light that is staying lighted. Something to check into tomorrow.

On a side note, got the head lights replaced with something a little newer and a little brighter. I also got the blower motor fan working again. The replacement fan blades were not fitting and causing a bind which overloaded the blower motor and blew the fuse. I just used the old blade again.

I am looking real forward to driving to work tomorrow knowing how fast I am going. (Go in the dark and come home in the dark) Looking forward to longer days too.

Thanks again.

 

[mistaken1]

Glad to hear you are making progress.

 

[Barrman]

Sounds like you got a fan and blower from a truck with A/C. Non a/c fans are different.

The low coolant light sensor is on the passenger side of the radiator. Unplug the wire, clean the plug and terminal then put it back together. They all flicker it seems. New senders are pretty cheap too.