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Discussion Starter · #1 ·
When I push the horn it works when the car isnt started, But when it is on and the lights are on the passenger side blinker is always slightly highlighted on the dash and when i press it the lights get slightly brighter. but the passenger side lights are always dimmer than the drivers side. The drivers side lights have zero issues. If you have any ideas please help.
 

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2004 chevy trailblazer_lt
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Welcome to the Forum!

You write "When I push the horn it works when the car isnt started, But when it is on and the lights are on the passenger side blinker is always slightly highlighted on the dash and when i press it the lights get slightly brighter. but the passenger side lights are always dimmer than the drivers side."

In the second line, you say "...when I press it the lights get slightly brighter..." What is the "it" you press whatever it is you press?

Also, do the exterior passenger side headlights (both low beam and high beam), turn signal light, fog light work normally? How about the horn - does it work when you press the horn areas on the steering wheel?
 

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Discussion Starter · #4 ·
it is the Horn. When I press any of the horn area it makes the right blinker light get brighter on the dash. And all the passenger side lights work they are just dim. And whatever is the issue is making them dim
 

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2004 chevy trailblazer_lt
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When you say they dim, are you referring to the what one would see if they were outside of your vehicle looking at it or are you referring to the lights on the instrument panel.

Also, what year, make, model and engine is this?
 

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2004 chevy trailblazer_lt
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OK, now we are making progress.

I am thinking that the problem is a bad ground connection. Lift the hood and on the passenger side of the body, right about where the middle of the tire would be if you were to cut it down the middle vertically under the body lip where the hood rests, there is a ground connection. Remove the fastener and make sure the area on the body is clean and shiny, and make sure the electrical terminal is also clean and shiny.

I've attached a pdf showing the location of this ground. All the lights you say that act funky when you use the horn, and the horn itself all use this same ground. So, when you activate the horn, something is causing the voltage to drop and the lights dim. The most likely explanation is a dirty or defective ground lead. So, while you are at it look over the wire that is attached to the terminal and make sure it is securely connected to the terminal and then follow it back into the wiring bundle to make sure it is intact.

If this does not solve the problem, let us know and we'll try something else, but this is the most likely cause of this problem, and the easiest (and cheapest) to repair.

Good Luck!
 

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Discussion Starter · #8 ·
So i tried cleaning the ground and it seems better? A little better anyway. So the passenger side blinker is still highlighted on that dash slightly even when nothing is being pressed. And when i press the horn in it still turns on the high beams for the passenger side. so im still super confused. Any other ideas?
 

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I would not worry too much about the blinker area being somewhat illuminated on the instrument panel. Likely caused by a backlighting bulb dying or you or someone else installed all new light bulbs and you are seeing light bleed.

Now pressing the horn turns on the high beam on the passenger side.

Doe the horn sound when the engine is off? Does the horn sound when the engine is on?

How long have you owned this TrailBlazer?
 

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2004 chevy trailblazer_lt
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OK on your having the TB for only 2 weeks.

I bet the previous owner attempted to replace some light bulbs that had burned out on the instrument panel and may have used a couple of different types of bulbs, or only replaced the burned out ones. As a result what you are seeing with the "turn signal indicators on the Instrument Panel is likely due to the [email protected] bulb replacement. Now, when you deliberately use the turn indicators, do the Instrument Panel turn signal indicators light up normally?

Now there is no delicate way to ask this next question so I am just going to come right out and ask it. Are you fairly mechanically inclined/experienced with "modern" vehicles with their electronic controls for everything and a handful of computer modules that control most everything?

How well are you equipped with tools and do you have a fairly decent Digital Multi-Meter (DMM), and a decent OBDII code reader/live data scanner?

Another question - do you know if the previous owner had an alarm system installed?

Please answer the questions honestly. We all started at ground zero at some point. Knowing your skills level will help with deciding to have you do a little "minor surgery" or really "major surgery" (sort of like a hang nail versus a quadruple cardiac bypass).

Thanks and good luck!
 

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Discussion Starter · #12 ·
I am fairly mechanically inclined i just dont like to mess with wiring when i dont need to. My dad pretty much has all the tools i would need. An OBDII scanner and multimeter aswell. No clue whether it had an alarm system installed. I actually have messed with wiring but if i do need like physical help my brother and dad know about everything i would need to know. They just are confused is to why my car is like this
 

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OK, sounds like you can handle a hernia operation :)

What I think is going on is that the wiring in the steering column in the area of the clockspring, horn contacts, and where the multifunction switch (windshield wipers, washer, cruise control, and turn indicators) all come together. This will likely involve the need to disable the airbag in the steering wheel, the need to remove the airbag, and then the removal of the steering wheel in order to inspect the wiring to see where the wiring is messed up. By messed up I mean it could be one or more of the following - worn insulation on one or more wires and the conductors grounding out or shorting each other, pinched wiring with the possibility of broken wires inside the insulation or wires grounding out if they make a sharp turn, or loose wiring.

Now you are going to need access to electrical schematics, and I do not mean the ones out of a Chilton's or Haynes Manual that you purchase at the auto parts store. I'm referring to model & year specific schematics. Here is a link to a professional level online Chilton's factory manual - McDowell County Public Library - Chilton Auto Repair

Now the one thing you must remember is that literally everything on these vehicles is controlled by a computer of sorts. When you turn the radio on, what happens is a request is made of the Body Control Module (BCM) to turn the radio on. If the BCM does not see any faults, it will commnd the radio to come on. When you turn an overhead light on, well, that switch you turn/press sends a request to the BCM to allow power to be applied to the overhead light. If the BCM does not see any faults, you will get light. Want AC, well, the BCM has to see that all the preprogrammed conditions present in it's memory are met and then it sends a signal to the HVAC controller in the dash to go ahead, and it sends a signal to the HVAC relay to ground allowing power to the AC compressor clutch.

Since everything works, but not to their fullest extent, I think the BCM is OK. It's just that when say you turn on the right turn signal, the BCM is getting "mixed messages" from the multifunction switch, the horn, etc., so it punts by letting the turn signals operate in a reduced capacity.

So, armed with a DMM, the schematics, a couple of extra sets of hands, and us on the forum, you should be able to straighten these issues out. Now, remember the following:

1 - Take lots of pictures before and during disassembly and try and get wires in focus, etc. Do not just take a couple of pictures up close and personal. Take a boatload of pictures so you can see landmarks like a special nut or bolt that allows you to line up a thing-a-ma-jig just right.

2 - DO NOT DISCONNECT THE BATTERY UNLESS YOU USE A KEEP ALIVE MEMORY DEVICE. Here is why:

DO NOT DISCONNECT THE BATTERY - REMOVE THE APPROPRIATE FUSE(S). Why? Because when you reconnect the battery, the HVAC actuators inside of the dash are commanded to run a recalibration procedure which stresses the old brittle plastic gears inside the actuators and the brittle plastic gears break and leaves you unable to control where the air comes out, or control the temperature of the air, etc. Replacing at least one of them literally requires the removal of the entire dash! So, if you ever need to actually disconnect the battery, such as in the case of needing to install a new battery, be sure and use some kind of Keep Memory Alive device to avoid the HVAC actuator recalibration routine.

OK, that is all I have for right now. Plus I have a no crank condition on a car that I have to resolve. I drive the car to where I could run an extension cord to it so I could charge it's battery and after the battery was fully charged, when I go to start it, it will not crank. I'm hoping it will be a fuse or a broken wire thanks to mice. and that it will be an easy fix.

Good Luck!
 
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When I push the horn it works when the car isnt started, But when it is on and the lights are on the passenger side blinker is always slightly highlighted on the dash and when i press it the lights get slightly brighter. but the passenger side lights are always dimmer than the drivers side. The drivers side lights have zero issues. If you have any ideas please help.
First thing, put in your, MAKE, MODEL of Vehicle. engine and anything you think will help,,,, or the pro will ask! I will tell you b4 the pros do, i think there's a leakie ground somwhere. aNS I'LL STAND BACK!
 
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