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Lightning audio B300.4 amp protect light

Hi, I own a lightning audio B300.4 amplifier, it is hooked to battery with 8g power cable and grounded to boot with same. Remote cable from headunit is hooked up. All of these cables are in the right places and nothing else is connected to it. The red protect light is on, and if i connect any speakers to it there is no sound due to the protect light being on. The fuses are fine, any ideas?

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The most likely reason for it to go into protect is shorted output transistors.

Posted on Jan 16, 2008


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SOURCE: Hi, I own a lightning audio B300.4 amplifier, it

sounds like amp is grounded. use a multimeter with ohms and test from pos to neg, should be o.l if there is any reading or resistance there the amp is grounded and junk

Posted on Feb 21, 2010

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Lightning Audio b2.3000.4 is in protect mode. i removed all speaks and conected the amp directly to the battery and it still stays in protect mode. what can i do to fix this problem?

  • Only a select few things can cause protect mode with the battery only connected.
  • An installation issue. Check the Power, Ground and Remote wires. Make sure non are shorting from one terminal to the other.
  • It is still overheated and has not had time to cool down from being in thermal protect mode.
  • The amp itself is touching metal. You always want something non conductive between the amp and where it is mounted, this includes the screws being used to anchor the amp. They should never touch the metal in the car either.
  • The final thing that can cause an amp to go into protect mode while only hooked to the battery is the amp itself is malfunctioning and or defective. You can try opening the amp and look for any black spots on the circuit board where an electrical component might have smoked up or blown and replace that part.

Regards, Tony

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I have a 1400 watt cruch amp & i hooked it up myself. when i turn the radio on the power wire on the amp comes on, bt if the audio cords are hooked up, the protection light comes on. if i dnt hook the...

Should the amplifier go into protect mode, simply disconnect all RCA and speaker leads, while keeping +12 volt, power ground and remote leads connected.

1. Now turn the amplifier back on, and if the diagnostic LED lights, the amplifier has an internal fault.

2. If not, plug the RCA cables back, and reset the amplifier. If it goes into diagnostic now, the fault lies in the input, either with bad cables or source unit.

3. If the amplifier seems fine with RCA cables plugged in, connect the speakers, one at a time, and if one of the speakers or its wiring is faulty, it will activate the diagnostic

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2 Answers

Hi, I own a lightning audio B300.4 amplifier, it is hooked to battery and grounded to boot with same. Remote cable from headunit is hooked up. All of these cables are in the right places and nothing else...

sounds like amp is grounded. use a multimeter with ohms and test from pos to neg, should be o.l if there is any reading or resistance there the amp is grounded and junk

Feb 19, 2010 | Car Audio & Video

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I have checked all connections to my amp battery,head unit,remote or trigger wire,fuses,power cable,rca leads,ground wire,amp has a green led light on it indicating if it works ok,red if it`s not,light...

Your amp could be in protection mode! Sometimes turning up to high or wires touching will put in protection mode! It will have to be unplugged for a day or two to drain all power out of the memory. Leave accessorie/ignition wire hooked up, just not power and ground wiring. It should reset itself.

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Lightning audio b150.2 as soon as +12 is hooked up blows 25 amp fuse and the c2 1000uf/35v capacitors blow???????

Disconnect all speaker connections and rca cables. Leave power, ground and remote wires intact. Try turning on again. If you still have a protection light your amp is faulty. Hopefully you have warranty. Double check all connections .A thumbs up would be greatly appreciated if this answer is helpful to you.

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Car subwoofer problems

The cable should not cause the problem unless it is shorting out somewhere on the remote or positive cable. I would use a larger gauge wire first as this is the cheaper way to go, and if the same problem occurs you are having a short in the sub or box causing the protection mode. You will have to back trace to find possible cross connections.

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Protect light comes on when rca cables are hooked up

Make sure you have a correct ground. Grounds will have problems doing this. Connect to a bolt, but make sure it isnt a colored one. Also make sure your rca cables arnt neg and connected to a positive :) haha

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Amp Not working!

If the amp goes into protect mode, it's likely due to shorted output transistors. To eliminate other possible problems, read through the following page:

Amp in Protect Mode - Troubleshooting

If the problems are not with the wiring, follow the link at the bottom of the page to the Amplifier Repair Primer page.

Let me know if you have any other questions.

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Directed audio 800a amp the protection light keeps blinking

1. Check your grounds. (including grounds for your stereo)

2. Check to make sure the power cable you connected to your car battery is properly connected, and not coming into contact with anything metal.

3. Make sure you are using proper fuses.

4. Check your connection from your stereo to your amp, and your amp to your subs.

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