WTF.. car problem has to be audio related

[aussiek2000 10+ year member]

you could unhook it. On my monte carlo, white is power on and orange is constant 12v.

 

[sandt38 10+ year member]

Hey all, I am new here but felt I could contribute here. I am a GM master technician with over 2 decades of professional experience.

99 grand prix gtp
ive tried to find the alternator size before but couldnt.. an its an ac delco battery.. not sure of size i dont have the car with me to look.. they are keeping it another day to make sure nothings wrong

i thought stock electrical could handle 800-900 rms.. am i wrong?

It should be a 120 amp alt, plenty of current for your system. On the GTP, with the blown 3.8, it may even be 130 or 140 amps.

I have a couple questions about your car. On your steering column, just below the ignition tumbler, is there a ribbed rubber cover that is almost square? Next, if this is the case, when you have starting issues, do you see the dash lights flashing, radio coming on and off, the horn just giving a quick honk, or any other weird behavior? Other common issues may be after you shut off the car the radio may stay on, and go off if you try roll up a window, or use your turn signal, or turn on your wiper switch. Have you tried to jumpstart the car with the dead battery? If you did try to jump it, please report on the result. I have seen some similar problems on GMs in the late 90s through current models and I may know what your problem is.

Still seems like something is draining the batt when the car is off. Check under the lower dash panels/behind the HU to make sure there are no small interior lights staying on.

This is a very common issue. Glove box lights, or trunk lights. But if the dealer really did test for a parasitic drain, they would have seen this.

where should i put the dmm leads to test for voltage drops? at the battery or back by the amp or doesnt it matter?

For a voltage drop test, you test the circuit in question while under a load. Test all connections on the circuit. When testing positive connections, place the + lead closer toward the battery, and the - lead closer to ground, across the connection in question. For the ground side, do the same... + closer to the device, and - closer to the battery negative. Electricity will follow the path of least resistance, so rather then crossing a bad connection it will travel through your DMM. The voltage registered on the DMM is the actual voltage drop. This will be the case on both power and ground circuits. For example, to test the voltage drop across your positive battery terminal (if it were a top post, yours is a group 78 side post) you would put the + lead directly on the battery post, and the - lead into the insulation jacket just after the connection. Then crank the vehicle, noting the voltage. Then, I would remove the - and reinsert it into the jacket at the starter. Then crank again. The difference between the 2 voltages would give you the cable's voltage drop, which may occur if there is corrosion inside the cable (a common problem on GM vehicles with group 78 batteries).

Acceptable voltage drops would be about 3/4 of a volt or less across the circuit, with a target of >1/2 volt.

Although I highly doubt a voltage drop is your issue.

Redlineaudio says,

you will not see a slow drain with a volt meter, you need to measure actual flow with a current meter.

and this is correct. The proper way to test a parasitic drain is to use either a DVOM capable of testing amperage, an older style 12 volt test light with a real light (not the small tube lights or LEDs), or an automotive light bulb (like an 1156) strung inline. There is a significant difference between a parasitic draw test, and a voltage drop test though //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif.
Now, here is the procedure for finding a system drain. Be sure to have the door switch closed when you do this, as the interior lights will reek havoc on this test, and be sure your hood light is disconnected. If you can get an assistant, have them watch the DMM, as it is more accurate. If you are doing it yourself take the test light, or inline bulb, and hook it in series like you did with your DMM, it should light up bright. With them connected, touch the cable and post together to charge any downed capacitors in the vehicle, and if it has timed interior lighting, hold the terminal until the lights time out, and do not remove the test light/DMM connections. Then separate the terminals. Now pull fuses in the fuse box one at a time. At some point you should see the light go out or really dim, or the DMM drop to just around .1 ampere. Again BE SURE YOU DON'T TRIGGER THE INTERIOR LIGHTS!!! When you pop the fuse and the current drops, you now have the circuit. Find out what's on the circuit and hunt it down.

 

[Redlineaudio 10+ year member]

^^^^^^^^^^^^^^^^^^^^^^^^^^^

Listen to this guy and ignore the rest of us.

 

[johnnyvolcom5 10+ year member]

x2..

 

[sandt38 10+ year member]

I have XBL2, Johnnyvolcom5... I would hate to think of being deprived of such glory.

2 Brahma 12s, and 2 Koda 10s.

 

[Jakeeck 10+ year member]

Hey all, I am new here but felt I could contribute here. I am a GM master technician with over 2 decades of professional experience.


It should be a 120 amp alt, plenty of current for your system. On the GTP, with the blown 3.8, it may even be 130 or 140 amps.

I have a couple questions about your car. On your steering column, just below the ignition tumbler, is there a ribbed rubber cover that is almost square? Next, if this is the case, when you have starting issues, do you see the dash lights flashing, radio coming on and off, the horn just giving a quick honk, or any other weird behavior? Other common issues may be after you shut off the car the radio may stay on, and go off if you try roll up a window, or use your turn signal, or turn on your wiper switch. Have you tried to jumpstart the car with the dead battery? If you did try to jump it, please report on the result. I have seen some similar problems on GMs in the late 90s through current models and I may know what your problem is.

This is a very common issue. Glove box lights, or trunk lights. But if the dealer really did test for a parasitic drain, they would have seen this.

For a voltage drop test, you test the circuit in question while under a load. Test all connections on the circuit. When testing positive connections, place the + lead closer toward the battery, and the - lead closer to ground, across the connection in question. For the ground side, do the same... + closer to the device, and - closer to the battery negative. Electricity will follow the path of least resistance, so rather then crossing a bad connection it will travel through your DMM. The voltage registered on the DMM is the actual voltage drop. This will be the case on both power and ground circuits. For example, to test the voltage drop across your positive battery terminal (if it were a top post, yours is a group 78 side post) you would put the + lead directly on the battery post, and the - lead into the insulation jacket just after the connection. Then crank the vehicle, noting the voltage. Then, I would remove the - and reinsert it into the jacket at the starter. Then crank again. The difference between the 2 voltages would give you the cable's voltage drop, which may occur if there is corrosion inside the cable (a common problem on GM vehicles with group 78 batteries).

Acceptable voltage drops would be about 3/4 of a volt or less across the circuit, with a target of >1/2 volt.

Although I highly doubt a voltage drop is your issue.

Redlineaudio says, and this is correct. The proper way to test a parasitic drain is to use either a DVOM capable of testing amperage, an older style 12 volt test light with a real light (not the small tube lights or LEDs), or an automotive light bulb (like an 1156) strung inline. There is a significant difference between a parasitic draw test, and a voltage drop test though //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif.

Now, here is the procedure for finding a system drain. Be sure to have the door switch closed when you do this, as the interior lights will reek havoc on this test, and be sure your hood light is disconnected. If you can get an assistant, have them watch the DMM, as it is more accurate. If you are doing it yourself take the test light, or inline bulb, and hook it in series like you did with your DMM, it should light up bright. With them connected, touch the cable and post together to charge any downed capacitors in the vehicle, and if it has timed interior lighting, hold the terminal until the lights time out, and do not remove the test light/DMM connections. Then separate the terminals. Now pull fuses in the fuse box one at a time. At some point you should see the light go out or really dim, or the DMM drop to just around .1 ampere. Again BE SURE YOU DON'T TRIGGER THE INTERIOR LIGHTS!!! When you pop the fuse and the current drops, you now have the circuit. Find out what's on the circuit and hunt it down.

hey man i think ur on to something.. one time when i went out to start my car it clicked a few times and died.. when i took the key out you could hear a weak horn beeping really fast.. idk how long it stayed like that because i left my car out in the parking lot.. when i had the key in though and turned it.. the horn would stop..

AND when the AAA guy was trying to jumpstart my car it would randomly honk at him.. it scared the shit out of him the first time.. he thought i was doing it.. eventually though the car would start and i took it to lynch every time right after it got jumped

edit: also trying to jump it with regular cars did almost nothing which is why i had to have AAA come out all 3 times.. and yes i do have that ribbed square thing

 

[sandt38 10+ year member]

OK, I would venture to guess your ignition switch is bad. If the dealer still has the car, you may want to run that by them. I have been replacing a lot of these switches, the electrical portion, for the most bizarre behaviors.

I have seen it on several Buicks, a couple Yukons, and it seems maybe a Lumina, or maybe it was a Malibu. Anyways, the issues all seem to be in the columns with that little rubber plug.

Hopefully this will help them isolate the issue, and good luck to you.

 

[Jakeeck 10+ year member]

OK, I would venture to guess your ignition switch is bad. If the dealer still has the car, you may want to run that by them. I have been replacing a lot of these switches, the electrical portion, for the most bizarre behaviors.
I have seen it on several Buicks, a couple Yukons, and it seems maybe a Lumina, or maybe it was a Malibu. Anyways, the issues all seem to be in the columns with that little rubber plug.

Hopefully this will help them isolate the issue, and good luck to you.

i actually picked it up yesterday because they ran out of ideas on what to test for.. they couldnt find anything wrong so now i have it again.. i just started it up today and i can tell something isnt right about it still.. it took a while to start up and it seemed like when it was cranking it was jumpy. i just took it for a 15 min drive and im gonna do that again later just to make sure i dont get stranded at school again tomorrow

ALSO.. i dont know if this means anything but when the car is dead its much harder to get the key out of the ignition.. i have to pull pretty hard and sometimes finagle with it... when the car is up and running i have no problems pulling the key out

 

[sandt38 10+ year member]

Pay attention for odd behaviors. The car should have the after run stereo, where it stays on after you shut the car off until you open the door. Try turning on the wipers, hitting your turn signals, rolling up/down the window and see if it shuts off or stuff starts freaking out. You may hear a bunch of clicks under the dash or under the hood, I have seen all the lights on the dash start flahing, and the door buzzer flashing in opposition to the dash lights (eg. Lights on/buzzer off, buzzer on/lights off). The switches affect a ton of stuff, so it is hard to pinpoint just 1 common thing, but opening and closing circuts seems to trigger their odd behavior.

 

[Jakeeck 10+ year member]

Pay attention for odd behaviors. The car should have the after run stereo, where it stays on after you shut the car off until you open the door. Try turning on the wipers, hitting your turn signals, rolling up/down the window and see if it shuts off or stuff starts freaking out. You may hear a bunch of clicks under the dash or under the hood. The switches affect a ton of stuff, so it is hard to pinpoint just 1 common thing, but opening and closing circuts seems to trigger their odd behavior.

ok so the key thing doesnt mean anything?

 

[sandt38 10+ year member]

Not likely, the key is a separate entity. If it has the pellet on the key, they will bind up sometimes. I know mine does, especially on a cold day!

And guess what just came in my shop? I have a Tahoe with a bad switch. I was just coming here to tell you that //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif

 

[Jakeeck 10+ year member]

Not likely, the key is a separate entity. If it has the pellet on the key, they will bind up sometimes. I know mine does, especially on a cold day!
And guess what just came in my shop? I have a Tahoe with a bad switch. I was just coming here to tell you that //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif

hmm im just curious.. how does a bad switch relate to my car dying?

 

[sandt38 10+ year member]

An internal short that keeps components on. If the switch stays on, the components keep running. The voltage is generally greatly reduced, for example the normally 12 volt circuit may only have a few volts, as several small circuits that are ground switched may be backfeeding ground to a power switched source. This is why the window motors will affect the radio during continuous after run play, because they are alternately switched ground, and the radio is switched power. What I generally see is higher current devices which use switched ground to prevent connector meltdowns common in Fords, use lower current devices that are obviously switched power to complete the circuit. I am not sure why I see so many of them with the turn signals creating issues, as these are power switched, but I do. My assumption is their close proximity to the ignition switch.

**Edit, also by reducing the voltage, we see a reduction in current draw, which may make finding a parasitic drain difficult.

 

[loopkiller 10+ year member]

Sandt38 sounds like a very informative guy. I would like to throw my hat in the ring here. What others have said is similar to my advice. You need to disconnect the sub amp and see if it is draining your battery when the car is off. I would not simply pull the fuses, I would remove the POS+ and Ground wires from the amp, of course making sure to cap off the POS+ wire and prevent it from touching anything metal in the process. I would drive it like that for a week and see if the conditions improve.

Now if they don't improve, you can take the amp out of the issue equation. Next I would pull out the HU and drive with no music for a week (sucks //content.invisioncic.com/y282845/emoticons/crap.gif.7f4dd41e3e9b23fbd170a1ee6f65cecc.gif) but it might be necessary. Again if the issue goes away, then you know that it is something with either the HU wiring or the HU may be defective.

If that does not resolve the issue, you can say the HU is fine, as well as the factory amp, since it too will be effectively disconnected as well. From there I would start pulling fuses for non necessary circuits until the culprit circuit is found.

My gut instinct says that sandt38 could be correct since he has much more experience with the vehicle than I do, but since the issue appeared after the audio install, unless it is just a fluke coincidence, something is wired wrong.

 

[Bobby12many 10+ year member]

**Edit, also by reducing the voltage, we see a reduction in current draw, which may make finding a parasitic drain difficult.

You are pretty smart for a n00b. //content.invisioncic.com/y282845/emoticons/crazy.gif.c13912c32de98515d3142759a824dae7.gif

//content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif