Light issues

[Twiz]

Just bought a 90 k2500 and my headlight lenses were really dark. Drove around with my brights on all the time. And also the left turn signal would flash fast. Figured that was a bad bulb but everything worked. So I bought an LED light kit from Amazon for $80, came with the headlights, front turn signals, 2 side marker lights (w/o LEDs, used factory bulbs), and the side marker reflectors. Plug and play set up. Installed them and all of a sudden when my lights were on my turn signals were always lit up. Didn't flash, just on. And when the lights were off if I hit the turn signal the headlight would flash with it. But everything worked. The left side didn't flash fast either. The left side turn signal bulb housing was coated in dielectric grease. I figured that was the problem and scraped as much out as I could. No change. Pulled my grill thinking I might have a problem with the headlights themselves but they were perfect. Fiddled around with the turn signal bulbs some more and realized they weren't in all the way. Headlights don't flash, all the lights work but the left side still flashes fast. Until I turn the headlights on, then the left side turn signal doesn't work at all. The running lights work, just no flashy flashy.

I read somewhere that LEDs don't require grounds, but this set up doesn't change the factory wiring. Just replaces the bulbs with LED gadgets. Not sure how it works but I know I don't have to change the wiring at all.

Any help would be appreciated.

[Twiz]

On another note, the 350 it has aftermarket headers and side pipes. W/O o2 sensors. How many is supposed to go on the truck and where? I've heard only 1 on the header but to me that doesn't make since cause there are 2 headers. The code reader I'm using says I've got an o2 sensor problem, obviously cause there are no sensors. I want to install one on each side, but if the OBD1 computer can't read 2 then I'll take just the one. I can't find the harness for it and my Chilton manual doesn't have it in the diagrams. If it's only one wire then I'll just run it myself but I'm not sure where it plugs in. I'm thinking the ECM.

Any help would be appreciated.

Thanks guys.

[68C15]

LEDs not needing a ground?! BS

It sounds like you had a ground issue in the beginning. Changing lights don't fix that.

Your engine is a single bank system, it only needs one O2 sensor. They assumed both sides wee running the same.

Side pipes on a K2500? We need pics

Ellsworth AFB, how's thongs on the west side?

[RayInAlaska]

Originally Posted by 68C15

LEDs not needing a ground?! BS

It sounds like you had a ground issue in the beginning. Changing lights don't fix that.

Your engine is a single bank system, it only needs one O2 sensor. They assumed both sides wee running the same.

Side pipes on a K2500? We need pics

Ellsworth AFB, how's thongs on the west side?

Two problems I can tell the OP is having with his lights:

a. The headlight leads aren't connected properly (wrong wiring connection).

b. The turn signals will flash at a high rate of speed because LED require the use of an LED-ready flasher, not the one he has had in his truck. Just go to an automobile parts store and ask for a turn signal flasher for LED lights.

But before doing that he has to address the wiring problem in his truck.

[Twiz]

I have a pic on my phone but have no cell service right now. Ill post when I get home.

and its only the one side that is having issues with the flasher. They all go to the same ground... Unless that particular ground wire has a bad connection to the bigger one that's grounded on the right side... Talkin to myself now, but at least things are clicking in my head.

With the O2 sensor, Is there a way I can run one on each side without having the computer re programed for it? I'm used to my 68 C10, all these new electronics and computers throw me off. Newest truck I've had in ... 10 years that I've worked on. Is it bad that I have to think about it?

[Twiz]

As promised, here is the pic.

[speedygonzales]

If the system is designed for 1 O2, there is no way to use 2. In fact trying to connect 2 will cause it to not function.

I also think you have a ground issue for your lights. You have to check the quality of the ground at each socket. Be sure you use a good method here such as a good multimeter.

With regard to flashing fast with a normal bulb, it would be either the filament is bad or there is a bad/broken connection. Again, ground check would be appropriate here. Use a conventional bulb to help with this problem before causing issues by using an LED.

To further what was already said with regard to LED's. Bulbs have an amount of load to the circuit. When a bulb burns out, the load to the circuit decreases and the remaining blinker bulbs flash fast. An LED does not load the circuit near as much as a conventional bulb and may not function so the circuit must be modified to accommodate the LED's. However, you don't want to troubleshoot the circuit with something that won't work correctly in the first place.

[68C15]

thats exactly why I at first said "bad ground". A bad ground in turn signal circuit will cause it to back feed in park light (head light also) circuit to ground. Park and turn at the small bulbs under the head lights share a common ground

[piecesparts]

I agree with the bad ground issue. The flashing of the headlight and the turn signal indicators on all of the time indicates that the circuits are searching for a ground to the lighting through another light bulb. Take some time to look at the wiring and see if there is a faulty wire somewhere or if someone has changed some of the wires around. Also from your pictures it appears to be time to replace the headlights and park lights on the truck.

[Twiz]

Originally Posted by piecesparts

Also from your pictures it appears to be time to replace the headlights and park lights on the truck.

Thats what started this whole feasko...

[piecesparts]

I replaced the ones on my 91 Silverado with ones from LMC and they are still clear and looking good after 4 years.

[Twiz]

Ok, so after tearing it down and putting it back together about a half a dozen times I finally found a relay for it at a parts store. Nobody really carries that relay around here. Fixed all my issues... So much worthless maintenance...

On another note has anyone replaced the dash in this style interior? I want to put an aftermarket stereo in it without it looking ugly using the eq/tape deck hole. But the hole for the stereo is about an inch smaller and a standard double din. I know they make a kit to put a cubby there but that just looks terrible to me. And I don't really want to build a custom dash to fit what I want.

Don't figure I'm gonna find what I'm looking for but I thought I'd try.

[piecesparts]

I had a pioneer radio in the center of the dash and a cubby hole pocket where the factory radio used to be on my 91. My XM receiver was inside the cubby hole.