Amp Going Into Protection Mode When Turning Car On

[tek_01]

hey all just put in a fusion 4 channel, soundstream 6.5 fronts and 6.5 inch fusions for the rears, i also have an alarm with built in turbo timer and also a keypad immobiliser (if that makes any difference) now it seems ive got a random problem which goes like this

when i turn the car on to accessories or reds, the radio works. than as soon as i turn the car on (which temporarily turn off cd player while its cranking the motor) the cd player turns back on but the amp goes into protection mode so no sound comes out of the speakers. Its got me stumped.

the amp and all speakers are brand new, and i have installed many systems before so i have a good idea on what i am doing. It seems like its getting some sort of voltage spike/drop which the amp doesnt like and goes into protection mode... im yet to measure it on a meter when i turn the car on

so than what i have to for it to work is switch the head unit off wait about 20 seconds than turn it back on and it works, or alternatively i can make sure the head unit is off before i turn the car on

anyone have any ideas? also to make it worse, it doesnt ALWAYS do it, just about 80% of the time

sorry for the essay but dont want to return the amp until i am 100% sure thats the problem (shop is a good 1 hr drive from my place)

[Chris Rogers]

sounds like a power issue. what are you using to run it and when was the last time you changed the battery?

[tek_01]

its a small battery, looks to be the standard one or at least the same size as the standard one as thee is a space to put a bigger one (extra securing point if u know what i mean)

car has no trouble turning on etc..

[skipppy]

not sure on fusion amps but alot have input voltage protection on rca, with head units cranking out fair voltage this could be the reason turn down the gain right to bottom on amp try again

Erin

[frx026]

its a small battery, looks to be the standard one or at least the same size as the standard one as thee is a space to put a bigger one (extra securing point if u know what i mean)

car has no trouble turning on etc..

not sure on fusion amps but alot have input voltage protection on rca, with head units cranking out fair voltage this could be the reason turn down the gain right to bottom on amp try again

Erin

Fusion amps do have protection for over and under voltage as well as thermal and of course overload.

I would look at the wiring, either there is a short with the key turned on, perhaps a speaker wire seeing a positive or a negative it shouldnt

The earth connection to the amp is loose and only becomes loose when the car is motion

The rca's are shorted and feeding direct dc voltage

The remote wire is dropping below 10.2 volts and may require a relay to be put in to boost it up a bit.

Not sure why i quoted everyone, maybe i just wanted to look cool in my first post of the year.

[BCMiller]

im yet to measure it on a meter when i turn the car on

This is where I would start.. The problem sounds like one of three things to me:

1 - Altenator regulator is putting out too high voltage.

2 - Amplifier has fault and is incorrectly reading high voltage.

3 - You have wired something to an earth that goes 12V+ or vice-versa when the engine is running.

The meter will quickly disqualify 2 of these possibilities.