2003 sierra dimming prob.

[jeremy.vaughn 10+ year member]

what do you do with the pos and neg of the voltmeter. also how do you measure the resistance of the extension wire..... which setting is ohms on the voltmeter

 

[jeremy.vaughn 10+ year member]

new problem..... the headunit will come on with the accessory on then it will go off when i krank the truck... other times it will work

 

[nimrod 10+ year member]

OK, you have two leads coming off of your meter(DMM). You want to set your meter to ohms. Take one lead and touch it to your amp grounding point, take the other lead and touch it to the battery ground and check the results. If your battery is too far away for the lead on your meter to reach it, you are going to have to put an extention wire from your neg. of your battery to your meter lead. Ideally you want your reading to be 0.0 Ohms. So the lower you can get your reading the better you will be. The ohm setting is usually the omega sign, or an O with two little tails at the bottom. Also ,don't worry about the pos. and neg. of your meter when checking resistance. Just put one lead on the amp ground and one lead on the battery neg.

 

[jeremy.vaughn 10+ year member]

alright thanks... ill let you guys know tomorrow afternoon what the reading is

 

[jeremy.vaughn 10+ year member]

how do you measure the resistance of the extension wire just connect one lead to one end of the wire and the other to the other end?????

 

[ado 10+ year member]

how do you measure the resistance of the extension wire just connect one lead to one end of the wire and the other to the other end?????

Yes.

 

[old_dude 10+ year member]

new problem..... the headunit will come on with the accessory on then it will go off when i krank the truck... other times it will work

I read this entire thread from start to finish and agree 100% with those people who are offering their advice and assistance. Great job, fellers!

But this one popped out at me: head unit goes off when you crank the starter. This, in my opinion, is normal. Mine does the same thing. Just momentarily, of course. But I think it's an internal safety feature of the deck or something. Most decks I've had did the same thing, even if power wired directly to the battery.

So, does your deck, when you crank the starter, power back up once the engine starts and is running?

Another thing that puzzle me was when you said all of a sudden your fronts and rears quit working. Odd. Oh, and do ONLY your dash lights dim to the music, or do your headlights dim also? If ALL lights dim, I would suspect many things but if ONLY dash lights dim I would narrow my trouble shooting on the headlight switch or dimmer.

I'm quick to admit I'm not MECP certified installer (I missed 3 too many answers on the test and failed:crying:, back in mid-90's) nor do I compete in IASCA sound-offs (but I'm a current member and also purhased the Competition Manual to use as a reference book). But I have experienced a lot of different things in my lifetime, and some were the same as you are going through.

The advice on relocating the ground wire is top-notch accurate!

And about using the meter to check your resistance is right on target!

But since different speakers work then don't work at different times, and stuff dims at different times, this is a perplexing situation and I'm becoming just as confused as you are. What I would do if this happened to me would be:

1. I would try a different amp first. (just for testing purposes)

2. I would try a different deck next. (again, just for testing purposes)

3. I would try a brand new battery, maybe different brand.

4. I would have my alternator tested.

5. I would check amperage current draw using DMM between power source and deck and also amps to see how much current (in amps, not volts) they are drawing off my battery.

6. I would torch my vehicle and start over! (kidding)

I really have no real answer for you but I will follow this thread and offer any advice I can if I get any brainstorm ideas. I just hope nobody slams me for the opinions I offered here. Remember, I have stated I'm not an expert.//content.invisioncic.com/y282845/emoticons/crap.gif.7f4dd41e3e9b23fbd170a1ee6f65cecc.gif

PS... the ORANGE fuse you spoke of is going to be a 40amp, 9 chances out of 10. It's basically the auto electrical standard color for 40amp fuses of any size or shape.

 

[jeremy.vaughn 10+ year member]

the radio and sub will work when you turn the key on... but when you start the vehicle the radio flickers on for 10 seconds then goes off,

the dash, headlights,interior lights{when on) dimm

i moved the ground to the frame and sanded it thouroughly.

the alternator puts out exactly 14.4 volts when running with the radio completely off.. ill post the resistance up later>>>>

 

[jeremy.vaughn 10+ year member]

the radio and sub will work when you turn the key on... but when you start the vehicle the radio flickers on for 10 seconds then goes off,

the dash, headlights,interior lights{when on) dimm

i moved the ground to the frame and sanded it thouroughly.

the alternator puts out exactly 14.4 volts when running with the radio completely off.. ill post the resistance up

allright

.1 to .0 for the extender wire....

amp battery to frame ground... 0.0

from the frame bolt to batt... a bunch of random numbers..

00.00 to amp negative...

hope this helps

 

[old_dude 10+ year member]

Pardon me for sounding like an idiot (again), but this thread was so long that I forgot... do you have your deck power wire hooked up into your wiring harness under the dash, or going directly to the battery? If into a hot wire under the dash, I'm guessing the problem could possibly be remedied if you disconnect the deck's power wire and run it directly to your battery and see if this helps. It almost sounds like there is a short somewhere but maybe not in the deck itself. Just a thought, but you can wait for better advice than mine.

 

[jeremy.vaughn 10+ year member]

its connected to the factory wireing harness

 

[old_dude 10+ year member]

Have you considered running it directly to your battery? I'm can't say your problem woud be solved for sure, but we always have a lot less "issues" if we run our deck's power wire directly off the battery.

I'm thinking something is shorting out somewhere. It seems like you've tried everything that other forum users have suggested but continue to have various problems.

I'll check back if I think of something.

 

[jeremy.vaughn 10+ year member]

hey i took out the fuze on my amp battery so that it would get absolutely no power. and i also unhooked the pos. wire that goes from my alternator to the extra battery. so basicly the extra battery is not doing anything....

i cranked up the truck.... and it worked just trebel because i unhooked the amp and battery..flawlessly all the way to school.

p.s. the starting battery was dead this morning.. and i had to jump it off.. i left absolutely nothing on in the truck..

but i WILL wire the headunit to the battery later on today......

 

[ado 10+ year member]

How are your two batteries and alternator hooked up?

Are you saying your main battery was dead with nothing left on?

 

[jeremy.vaughn 10+ year member]

allright.... the starting battery just has the factory wireing to it... and yes it went dead last night with nithing left on. but it gragually started turning the truck over slower... over a period of several days...(starter spun slower)

as for the amp battery it is hooked up to ONLY the amp.... it has the big 3 done to it..

the alternator has an extra lead/power wire connected to the back of it to charge my extra battery..... hope this is helpful