So I got a DMM yesterday........

[TurdFergueson2 5,000+ posts]

So I was having a issues with my amps cutting off and some other things. I read up on it a bit here and people were suggesting getting a DMM. I went so my local Sears and after the dude at the register could not help me, I settled on this one.

http://www.sears.com/shc/s/p_10153_12605_03482139000P

One reason I chose this one is because it can measure frequency as well. My question other than how the hell do I use it is, should I have got the one that does manual range? That's what the guy at the counter couldn't tell me.

Click to read more...

 

[dman4486 5,000+ posts]

//content.invisioncic.com/y282845/emoticons/rolleyes.gif.c1fef805e9d1464d377451cd5bc18bfb.gif

Read The Manual!!!!!

 

[djman37 5,000+ posts]

So I was having a issues with my amps cutting off and some other things. I read up on it a bit here and people were suggesting getting a DMM. I went so my local Sears and after the dude at the register could not help me, I settled on this one.
http://www.sears.com/shc/s/p_10153_12605_03482139000P

One reason I chose this one is because it can measure frequency as well. My question other than how the hell do I use it is, should I have got the one that does manual range? That's what the guy at the counter couldn't tell me.

that isn't what you think. set it to DC volts to read your battery voltages.

 

[Ali1 10+ year member]

you can hook up the + and - lead to your battery to see its resting voltage(when the vehicle is off) and when the car is on (to see if your alternator is properly charging it).

Also, measuring your ohmload at the speakerleads on the amp is another option. Check to see if you wired your subs correctly. You can also check your amps voltage and voltage drops while music is playing.

its a great handy tool

 

[GearGuy2001 10+ year member]

Even though its an autoranging mm you can manually pick the range by pressing the "Range" button at the top. This has come in handy for me on my mm a couple of time but usually I let it auto range.

Also is your remote wire loose that might be triggering your amp cut?

 

[TurdFergueson2 5,000+ posts]

Even though its an autoranging mm you can manually pick the range by pressing the "Range" button at the top. This has come in handy for me on my mm a couple of time but usually I let it auto range.
Also is your remote wire loose that might be triggering your amp cut?

Always the little things I guess. I figured since everything came on there was no need to recheck.

 

[GLN305 10+ year member]

So I was having a issues with my amps cutting off and some other things. I read up on it a bit here and people were suggesting getting a DMM. I went so my local Sears and after the dude at the register could not help me, I settled on this one.
http://www.sears.com/shc/s/p_10153_12605_03482139000P

One reason I chose this one is because it can measure frequency as well. My question other than how the hell do I use it is, should I have got the one that does manual range? That's what the guy at the counter couldn't tell me.

Autoranging meters will work well for you. Just read up on the meter and then familiarize yourself with what you are looking for and where it is. For instance:

Input from car battery is DC voltage as well as the remote turn on.

Output from amp is going to be AC voltage and if you insert a CD with a test tone or white noise you can get a steady reading from the meter.

The speakers are going to be read using the resistance setting. Keep in mind that the number you will see will no match the speaker impedance because impedance is a combination of resistance of the voice coil and the inductive reactance of the voice coil at a specific frequency. Just keep it simple and if you see 3.5 ohms or so it's a 4 ohm speaker. Usually the resistance is a little lower than the impedance.

You can also use the meter to check your ground. Using the resistance setting on the meter, just place one meter lead on the negative terminal of the amp and place the other lead on a good bare metal surface on the car, you want the resistance to be as close to zero as possible. If you are over one, fix your ground.

Good luck.

 

[jrwalte 10+ year member]

a weak ground where the amps ground can cause them to shut off under heavy load. At lower volumes everything may seem fine, but when you increase the volume and the amperage demand of the amps, if the ground is weak, it can't get the power it needs and shuts off. Only the amp demanding the large amperage may shut off while the other keeps working without issue.

This issue can also cause voltage dips in your electrical which can make it look like your current electrical system can't handle the demand, when it actually can.

How are your amps grounded and when did you last check it? Grounds can get loose.

 

[dumple 5,000+ posts]

i have a field piece with clamp attachment i loves it

 

[TurdFergueson2 5,000+ posts]

a weak ground where the amps ground can cause them to shut off under heavy load. At lower volumes everything may seem fine, but when you increase the volume and the amperage demand of the amps, if the ground is weak, it can't get the power it needs and shuts off. Only the amp demanding the large amperage may shut off while the other keeps working without issue.
This issue can also cause voltage dips in your electrical which can make it look like your current electrical system can't handle the demand, when it actually can.

How are your amps grounded and when did you last check it? Grounds can get loose.

The 1900D is fine, the kicker amp goes into protect when played loud. Gains are more than modest on that one. I tried it with an 800 watt street machine and it does the same thing. Only thing I haven't looked at was the remote wire as was suggested

I have the grounds going into a non fused distro and bolted to the bolt under my rear seats. Haven't had a problem till i went trying to tighten everything up last weekend when the weather broke.

My plan was to tear the whole thing down and re do it the right way. I figured a DMM was a good start.

 

[jrwalte 10+ year member]

So you're saying it played fine until you tightened everything up last weekend? Take a voltage reading at your batt with your car running and then a reading at your amp. If you have more than .1 voltage drop you may want to consider moving your amp ground. Most people recommend to not ground to a seat bolt. I grounded directly to my frame inside my spare wheel well with a Streetwires grounding block.

You can also try the ohm resistance test at your grounding spot.

Set your DMM to Ohm. One end of your DMM has to touch the bat ground and the other end has to touch the ground spot you want to test.

Touch the DMM to the bat ground and the metal spot where the bat ground touches the chassis. This is the amount of resistance your ground is receiving to make it from your chassis to your battery. It should be 0 or .1, .2. Anything over that and you may want to clean/sand/pick a new bat to chassis ground.

Before you do the next test, make sure your amps are disconnected from the ground wire or at least your RCAs are removed. You could have a bad ground spot but get a decent reading because your RCAs provide a better ground route that the DMM reads. But your RCAs grounding through your HU to your bat with a lower resistance than your ground spot is obviously a bad thing. You want your ground spot to have a lower resistance. It may be good to test it both ways to ensure your RCAs aren't creating a better ground path.

To get your DMM to reach your trunk ground, just use a spare piece of wire to run from your battery to your ground spot (you also want to get an ohm reading of this piece of extension wire. If it's anything above 0 you have to subract that from the ohm reading you get). You want an ohm reading under 1, otherwise your ground location has too much resistance to reach your battery.