A list of electrical problems. Please help

[TSewell]

Here is a list of electrical problems.

#1. I have no park lights. In order to have running lights while the lights are on, i had to run a jumper wire from the headlights to the junction block running into the firewall.
#2. When i turn on the brights i loose all dash lights, and the rear cargo light comes on.

To answer the obvious question, Yes i have checked the fuses.
I am at the point where i am going to run the park/running lights, low beam, high beam, and interior lights off of toggles.
Can someone help me with this?

 

[goathearder]

Sounds like it might be a problem with the headlight switch itself, have you replaced that? They can be had fairly cheap from rock auto (like 10 bucks) and if its like my blazer it control the headlights, park lights, dash lights and interior lights. If there is a gremlin somewhere, I'd start with that.

I was having problems with my interior lights and they went away when I replaced the switch.

 

[TSewell]

Sounds like it might be a problem with the headlight switch itself, have you replaced that? They can be had fairly cheap from rock auto (like 10 bucks) and if its like my blazer it control the headlights, park lights, dash lights and interior lights. If there is a gremlin somewhere, I'd start with that.

I was having problems with my interior lights and they went away when I replaced the switch.

Yup, replaced the switched, twice.

 

[lugnut]

Most electrical problems can be traced back to a bad ground. I would bet thats the case for the dash lights. They are probably grounding through the hgh beam indicator. When it trys to come on with the high beams they loose that path to ground.

Parking lights if I remember correctly (dont have a diagram) they have a separate positive feed to the switch than the headlights. I woulld look at that.

 

[TSewell]

Most electrical problems can be traced back to a bad ground. I would bet thats the case for the dash lights. They are probably grounding through the hgh beam indicator. When it trys to come on with the high beams they loose that path to ground.

Parking lights if I remember correctly (dont have a diagram) they have a separate positive feed to the switch than the headlights. I woulld look at that.

Well i guess i will rip apart the dash again and look. Thank you!
Another problem is that the front floor light will not come on when you open the doors, just the rear cargo light. The front floor light will only come on when the headlights are on and you turn the knob over to turn on the interior lights. WTF......its such a nightmare. I am about to just drop it off and pay someone to figure it out.

 

[Jessie James]

Electrical problems can see daunting at first, but what they really require is patience and simple testing tools.

Probably the most important thing to do is look for any wiring hack jobs the PO may have done. Do you see anything cut, spliced, moved, added, or removed? If so, try to get that straightened out or removed and back to original.

Is there an aftermarket alarm? Remove it!

All you really have otherwise to do is follow the wires, every inch, to see what is going on.

You say you run a wire from the battery to the junction box for the running lights, right? Okay, so stop and think about that for a few seconds (maybe a few minutes). WHY is no power getting to that junction box? Find the hot wire that goes to the junction box that is supposed to supply power, and follow it all the way back through the truck. You may need a helper to pull it a little from the engine compartment so you can see where it comes through the firewall, or maybe not.

Using a tester, check for 12v at every spot you can. Is there 12v at the junction? Is there 12v at the output side of the headlight switch, when turned on? Is there 12v on the supply side of the switch with the ignition on? Is there 12v at the fuse? Where does the 12v disappear and it shouldn't?

WHERE is the lack of power originating from?

You say you replaced the switch, was it a new switch? Are you sure it's working? Is it the EXACT CORRECT PART for your truck? Again, using a tester, test the switch itself (you may have to pull it out to get to it). Using a continuity tester, put one lead on the supply side and one lead on the output side, and turn the switch on. Are the right leads connecting?

Are there any items in the supply stream that could have gone bad, like a bad relay? Test that.

Check all grounds. Remove each bulb and look in the socket. Is it nice and clean? Or is it corroded? Is the actual bulb housing solid? Sometimes the wire going into the socket is damaged, and wiggling it causes problems.

Basically, just take your time and follow a wire with your tester.

 

[TSewell]

I am going to get the help of a freind and pull the whole dash out, again, this weekend and see if i cant figure this out. I will post pics of anything out of the ordinary.

 

[Jessie James]

Honestly, the only reason I would pull the dash is if it was clear there was a lot of wire hacking under the dash, or if I could see obvious visual evidence of water leaking past the windshield seal and into the fuse box. If the under side of the dash is dry, clean, and looks factory, I'd just stick to following the basic wires as best as possible.

You may be able to solve this in 10-20 minutes if you just follow the wires. Doesn't taking the dash out take an hour? And if you're like me, you lose a bolt, break something, or ground something out accidentally!