2005 Dodge 1500 Electrical help

[LD1]

Hoping someone can offer some assistance on some multiple electrical (lighting) issues I am having.

It would probably be easier to list off the lights that DO work, but here is a list of those that dont:

Left Tail light
Left turn/brake
Both backup lights
Center high mount stop lamps
Both front turn signals
Right high beam
Left low beam

The headlight "bulbs" are fine. Took them out, filaments intact. Both bulbs will light up on high on the left side, but neither will light the low beam on left side. They will both light the low beam on the right side but not the high. So not the bulbs. Something in the wiring.

The left taillight/brake/turn assembly......it all works when plugged into the right side, so not the circuit board or bulbs in that either.

Dont know on the backup lamps or front turn signals because NEITHER side works so I cant swap to test bulbs. But filaments are intact as well, and given the issues with the other lights, I dont suspect the bulbs.

Some googling lead me to a connector under the driver side floorboard as a potential problem area/corrosion/etc. But took that apart and all look clean and tight.

Given the numerous lighting issues that seemed to happen all at once, I am inclined to thing this is a single problem area. But dont know what is common to all or most of the things I listed.

Aint gonna have time to look into anthing til tomorrow, got the shop tied up for my sons birthday party here in an hour or so. And havent put the multimeter on anything yet. Just looking for some so insight before i get started into it tomorrow.

And if anyone has a link or access to a wiring schematic that they would be willing to share, that would be awesome too.

 

[Redlands Okie]

Have the computer checked. My 2006 dodge has the so called fuses that are actually auto reset deals in the main computer. After they trip a few times you have to have the trucks computer cleared. I have this issue with wiring going to the trailors mostly but have had issue on the truck lights. This may not be the problem but it worth looking at

 

[dodge man]

Going by memory here as it's been a while since I owned one but check the are under the fuse box. I think there is a bunch of connectors under there that can get gummed up. Also I think your truck has a computer that controls all that stuff. Body control module?? Probably expensive for a new one.

 

[LD1]

Didn't see a bcm unless that's the box beside the fuse box. All the wires run straight from under the fuse box to the main harness that runs back to the back. Only junction is the plug I already mentioned.

I was planning on taking the fuse box out to check the plugs underneath as I saw that mentioned online.

I was able to reach them from the underside and wiggle them all around and back and forth. So I would have though bad connections/corrosion their being the issue I would have thought I'd seen some improvement. But no change

 

[3930dave]

I haven't logged in here to check, but I think a buddy of mine was able to get some schematics for one of his vehicles from the Autozone site 2 or 3 years back.

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Up here, some of the retail aftermarket parts suppliers will have access to ShopKey or something equivalent - stop by some of your local parts shops and ask, they may be able to print schematics for you.

If you have anything like the Winter salt we do here, I'd vote for pulling the fuse box for a visual check - I've seen major wire rot on that vintage of truck here.

Rgds, D.

 

[LD1]

Update.

Chmsl works. Bad bulb.
Left tail light works....I broke a ground to it the other day when frustrated and pulling tape/wireloom off.

Backup lamps on that side also works. Now that ground is fixed. Right side backup has melted circuit board.

So....still left with
Left rear brake/turn don't work. Wiring from fuse box back is good. Cause it's the green wire with a white tracer, and normally has 9v on it but when 12v is applied it lights brake/turn. Manually applying 9v and it lights.

Front turnsignals just don't work. Haven't looked much at that.

Front headlights still the same. One high works, opposite side low only.

But when testing voltage on driver side at the plug, center wire ground.....from it to one wire shows 10.5v and 8v from center to other. Switching from bright to dim don't change any voltage readings (yet bulb goes out as it only works on high).

Very puzzled. Changed the FCM on the side of the fuse box with the one out of my Dodge..no change so that ain't it.

 

[LD1]

Problem solved if I can source a good part.

Integrated power module.

Basically what all the fuses and relays hook into. Its a computer of sorts. Swapped it with the one in my 3500 and everything works fine

 

[LD1]

 

[3930dave]

Problem solved if I can source a good part.

Integrated power module.

Basically what all the fuses and relays hook into. Its a computer of sorts. Swapped it with the one in my 3500 and everything works fine

Nicely done. Sounds like a trip to the boneyard is in order....

Stock up on dielectric grease if you are low/don't have any.

Rgds, D.

 

[dodge man]

I suspected that was what the problem was. I just didn't know what to call it. I used to own a 2004 Cummins and was on the Cummins forums some and that was a very common problem. Another common issue is the tail light boards. Once again, I'm not sure what they are called, but its what your light bulbs plug into. They are really cheap and can be bought at a parts store. If you still have problems with the rear tail lights, I'd replace those also, they just plug in and are easy to replace.