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Discussion Starter · #1 ·
Came home one night to find my rt front park lamp was lit- no other lights were on- any suggestions as to cause? anyone else ever had that issue? I either have to unhook battery or pull out park lamp bulbs otherwise battery dies. What would power this lamp and only this lamp? Unhooked headlamp switch & replace signal lamp switch and light still on. Must be a short somewhere but where?
 

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2000 Silverado Z71 4x4 5.3L 480k+ miles w/ GM rebuilt motor and trans
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Make, model, year, good sir?
 

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Discussion Starter · #5 ·
HI Ray- both upper and lower are park/signal lamps. headlight are daytime running lights. Upon further investigation discovered it is not the park lamps that are on- it is the signal part of the bulb. Now I've gotta find out where they hide the flasher and check that out. Still confused why only the front lamps are on and not the rear also. Thanks for the reply- will let you know what I find if anything.
 

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Discussion Starter · #6 ·
HI Ray- both upper and lower are park/signal lamps. headlight are daytime running lights. Upon further investigation discovered it is not the park lamps that are on- it is the signal part of the bulb. Now I've gotta find out where they hide the flasher and check that out. Still confused why only the front lamps are on and not the rear also. Thanks for the reply- will let you know what I find if anything.
yes that is my front end.
 

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Bondo, your flasher is built into the Body Control Module.
I'm not finding fault with your observation; but I don't recall ever seeing 2 bulbs flash at the front of any truck.
What happens on the other side if you use the flasher for that side, do you have 2 lights flashing?
What happens to the faulty side if you use the flasher for that side?
How about the 4 way flashers?
And, your mirrors should have a flashing light when using the signals, does that light on the faulty side?
And, if you remove the signal fuse does the light go out?
Sorry for all the questions!
 

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Discussion Starter · #8 ·
Hello Ray- just checked my truck- driver side lights work normally- both signal and 4 way modes. My truck has an upper and lower bulb on the side/signal/park lamp section of the headlamp assembly. Rt side rear light flashes fast- like it would with a bulb out somewhere else. Rt front bulbs (2) flicker very slightly in signal and 4 way modes. Headlights are daytime lights, there are no indicator lights in mirrors- my truck doesn't have them. Don't worry about asking questions- I appreciate the info you are providing. If the flasher is in the BCM, I'm thinking it is bad- Your opinion?
 

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2000 Silverado Z71 4x4 5.3L 480k+ miles w/ GM rebuilt motor and trans
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If the flasher is in the BCM, I'm thinking it is bad- Your opinion?
I'm thinking you have a short, not necessarily a bad BCM. Have you had any work done or done any work on the truck in recent history? Perhaps a wire got pinched or chewed?
 

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Discussion Starter · #10 ·
will be out for awhile- will get back to you later- thanks
I'm thinking you have a short, not necessarily a bad BCM. Have you had any work done or done any work on the truck in recent history? Perhaps a wire got pinched or chewed?
I thought of a short, but why only the front lamp lit, and what powers the lamp? According to RayVoy the BCM does so it makes sense (I THINK) that's the problem. All the rest of the lamps work normally. This has got me stumped, but that doesn't take much now a days. Thanks for your thoughts- I will post correction when I get it fixed.
 

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Bondo, BCMs fail; but not often, I wouldn't go there yet.

Let me think about this for a little awhile, we just got 4, or 5, inches of snow changing to rain tonight and I need to clear the driveway.
 

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Sorry, didn't get back to you last night.
Did you try pulling fuses to track down the source of the power for the light?
As you know, the signals need the key on; but the hazards will work with the key off and in your pocket. The BCM is the flasher for both..
But both use switches to tell the BCM to start flashing.
Both circuits share a lot of parts, like the multifunction switch in the steering column, the may share the fuse as well.
 

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Discussion Starter · #13 ·
I did pull fuses, but not all. I'll go that route again and pull them all, and get back to you. Thanks
 

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Discussion Starter · #14 ·
I'm really stumped on this one. I pulled ALL the fuses, including the "J" fuses, and ALL the circuit breakers including on the left side of the dash and the lights never went out. I did notice my license plate lights are out- doesn't seem to be any power going to them. 5 gallons of gas and a match will take care of the problem, but in lieu of that-any ideas? I hate to take it to the dealer at $149.00 per hour.
 

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2000 Silverado Z71 4x4 5.3L 480k+ miles w/ GM rebuilt motor and trans
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Beyond a short under the fuse box or in the wire somewhere... 🤷‍♀️

Where is your battery located? Any wires rubbed together and shorting out through the lights?
 

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Discussion Starter · #16 ·
battery is underhood- rt front side. Most all of the wires are in convoluted tubing, and light came on even though vehicle wasn't being driven. I thought of a mouse or squirrel issue, but they don't usually nest in vehicles that are frequently driven and I have 15+ vehicles on my property that they'd probably pick before this one. Really got me on this one and it's so hard to try to trace wires that run mostly on the lower part of the vehicle.
 

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Discussion Starter · #18 ·
found diagram on net after searching for 1/2 hr. ,but didn't show anything that really grabbed my attention. HELP!!
 

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The right side signal wire is always dark blue (think about hooking up trailer lights).
You must have that wire shorted/crossed with a non fused red battery wire. The one that jumps to mind is the big one going to the starter.
 

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Discussion Starter · #20 ·
I'll have to check it out tomorrow- can't understand how or why that would be. This is getting discouraging- but it's $149 an hour at the dealership to check it out. I wish I had a service manual with a good wiring diagram. The problem is who knows where the wire is routed- it's all hidden in the tubing and runs under the radiator- I think I'll have to pull the radiator out to get to it. GRRRRR! Thanks
 
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