Lexus LS400 Amplifier Overheating

I need help troubleshooting this Lexus install. Upgraded all power wire from 8 to 4gauge wire. Replaced 3 seperate amps and all three seem to be getting hot. I scraped the hell out of the ground connection on the chasis, it too has a 4ga connection 4in long and for some reason or another I still cant get the amps cool enough. Does it have something to do with the sound densening material in the lexus that dosent allow for adequate air flow in the trunk? It has also 60 amp inline fuse from the battery. Running 2 12 in JL audio single coils with an earthquake PH150.2 amp, ran speakers at 2ohms, amps got hot, brought the ohmage back up to 4 and amp still got hot. Repalced the PH150 with a sony Explode 1000watts, ran it at 4ohms for about 45 min and it was hot to the touch. Any suggestions? Please reply!

Try a 12 volt computer fan from radio shack.Certified Security Specialist

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Where is the ground made and did you check it to see what the resistance on the ground return is? With limited air circulation an amp in a trunk will get hot, even more so in the coming months. Waht is the gain on the amp set to? Are you using a bass boost? Is this consist loud listening levels or moderate volume levels? An amp is designed to get hot, not excessively hot, is the amp actually going into thermal protection?Top Secret, I can tell you but then my wife will kill me.

I was considering putting a 12v computer fan in place where the 8in factory sub is located in the back dash. Gain is set to 0 to 1/4 of the way, I have never exceeded the half mark. This amp comes with dual eq knobs one controls 45 hertz and the other is 125hz, the 45 is set at the 1/2 mark and the 125 is set at 9 o clock. Volume on head unit is set to 3/4. The ground is fastened to the body of the vehicle. The heat that the amplifier is producing way exceeds the general heat that an amp would produce in normal operation. The thermal protection will kick in or the fuse in the amp will blow after about 30 min. I initially thought that one of the transistors was about to give, but when I swapped the earthquake out and hooked up the sony explode, the sony did the exact same thing, but the earthquake was put in a 94 yukon with 2 12in sony explodes 1200wts (so they say) and performed absolutely perfect for 45min play. I have been reading into some other sites and they discuss the remote as a possible cause? I may have overlooked a knick in the wire...could this be a possibility?

Instead of putting a comupter fan, better find the source of the excessive heat. A 12v fan won't solve the problem but just aleviate it. Like taking a pain killer rather than stop the pain. Are you running the amp at high volume? If it is getting too hot even at very low volume, there's a problem to be solved. Amps do get hot but if it goes into thermal protection, yes its getting overheated.

Thanks everyone for your replies, but Im still in the same situation as yesterday, with no solution to the problem. I'm Guessing that there's a problem with the remote, if not, I have no other choice but to rewire this whole setup ****! I've been doing this **** for 6yrs and this is the first car that has given me nothing but headaches from the get go. I usually don't ask for other installers help, It's not very common for installers to ask other installers for advice, cuz if you don't know what your doing you shoudn't be touching it. This seems to be an uncommon delimma, so if there is any expert advice toward a solution, I'd certainly apprecicate their opinion.