No More BOOM!

ctuna · 06-13-2014, 02:10 AM

To test for low resistance
Set the meter for the lowest scale.
Touch the leads together it will usually measure .1 .2 or some small
number. That number gets subtracted from your actual reading to come
up with a true value. You only have to do this when measuring small
resistance values 10 ohms and under.

mathematics · 06-13-2014, 08:40 AM

Absolutely. If you're cranking the radio and your amp pulls 50amps, but your fuse is rated for 20 amps, it will 100% blow. You need to know what the proper fuse size is for that amp. I'm not familiar with the JL amp, so maybe someone else can chime in.

E92TTCoupe · 06-13-2014, 12:30 PM

Quote:

Originally Posted by ctuna

To test for low resistance
Set the meter for the lowest scale.
Touch the leads together it will usually measure .1 .2 or some small
number. That number gets subtracted from your actual reading to come
up with a true value. You only have to do this when measuring small
resistance values 10 ohms and under.

Which point or what area am I testing that way I know what exactly what I'm doing.

E92TTCoupe · 06-13-2014, 12:31 PM

Quote:

Originally Posted by mathematics

Absolutely. If you're cranking the radio and your amp pulls 50amps, but your fuse is rated for 20 amps, it will 100% blow. You need to know what the proper fuse size is for that amp. I'm not familiar with the JL amp, so maybe someone else can chime in.

Got it. Thank you for that. How can I find out the proper fuse size for the amp? Would the manual tell me?

mathematics · 06-13-2014, 01:15 PM

Yes, the manual will tell you.

bmw325i · 06-13-2014, 03:59 PM

Quote:

Originally Posted by mathematics

Absolutely. If you're cranking the radio and your amp pulls 50amps, but your fuse is rated for 20 amps, it will 100% blow. You need to know what the proper fuse size is for that amp. I'm not familiar with the JL amp, so maybe someone else can chime in.

The inline fuse is to protect the power wire not the amp so it should be properly sized for the wire gauge. Should be about the same amperage or a little more than the fuses on the amp.

Real 8 gauge is good for about 60 amps
4 gauge 100 amps
0 gauge 200 amps

Since the power wire is so short they can actually handle more power than that, but better safe than sorry.

ctuna · 06-14-2014, 01:00 AM

Put on Lead on the Amp Ground and measure to the ground nearest the battery . The most likely problem point is where the ground wire for the amp is attached to a ground point on the car chassis.
Do the same for power but use the positive connection on the end of your power cable.

JL audio should have a suggested fuse rating.
You may have to call them for it.

06-13-2014, 02:10 AM	#23
ctuna Lieutenant General 2045 Rep 13,359 Posts Drives: 325xi 06 wagon MT Join Date: Jan 2010 Location: Santa Cruz, Ca iTrader: (0)	To test for low resistance To test for low resistance Set the meter for the lowest scale. Touch the leads together it will usually measure .1 .2 or some small number. That number gets subtracted from your actual reading to come up with a true value. You only have to do this when measuring small resistance values 10 ohms and under.
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06-13-2014, 08:40 AM	#24
mathematics Captain 71 Rep 994 Posts Drives: 08 328i e93 alpine white Join Date: May 2009 Location: Queens, NY iTrader: (0)	Absolutely. If you're cranking the radio and your amp pulls 50amps, but your fuse is rated for 20 amps, it will 100% blow. You need to know what the proper fuse size is for that amp. I'm not familiar with the JL amp, so maybe someone else can chime in. __________________ iPhone 6 Plus (iTunes library/iTunes radio/Waze, etc) to Airport Express via AirPlay. Toslink out of Airport Express to Helix P-Six DSP. PHD AF 1.C tweeters, PHD FB 4.1 midranges. Jehnert Door Cards and mid-bass'.
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06-13-2014, 01:15 PM	#27
mathematics Captain 71 Rep 994 Posts Drives: 08 328i e93 alpine white Join Date: May 2009 Location: Queens, NY iTrader: (0)	Yes, the manual will tell you. __________________ iPhone 6 Plus (iTunes library/iTunes radio/Waze, etc) to Airport Express via AirPlay. Toslink out of Airport Express to Helix P-Six DSP. PHD AF 1.C tweeters, PHD FB 4.1 midranges. Jehnert Door Cards and mid-bass'.
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06-14-2014, 01:00 AM	#29
ctuna Lieutenant General 2045 Rep 13,359 Posts Drives: 325xi 06 wagon MT Join Date: Jan 2010 Location: Santa Cruz, Ca iTrader: (0)	To test ground an power for low resistance Put on Lead on the Amp Ground and measure to the ground nearest the battery . The most likely problem point is where the ground wire for the amp is attached to a ground point on the car chassis. Do the same for power but use the positive connection on the end of your power cable. JL audio should have a suggested fuse rating. You may have to call them for it.
	Appreciate 0 Quote