Amp is going in to 'Protect' mode when I turn up the volume.

[SCaliber]

I found my way to these boards out of desperation, but I'm hoping to stay since it seems rather neat.

In any case, I installed my new sound system into my truck a little over a week ago, and it was running great until two days ago. I just turned the truck on, and I noticed if I turned up the volume that the speakers would cut off and the amp goes into a protect mode. I've tried turning down the gain, volume displacement, and bass boost, but it still does it. I can turn the volume up to a higher number than before though, but my stock speakers in the back over power them. Any ideas? I also tried to give a better ground too.

My equipment:

Rockford Fosgate Punch P400-4 (It's true rating is at 500~ at 2Ohms)

2 x JBL GTO938 ( 100W at 2 Ohms)

2 x Kicker 6.5" CompVT Car (125W at 2 Ohms, also these are NOT hooked up at the moment, because I'm having a hard time find room to make it look stock still)

Click to read more...

 

[jasonAz 10+ year member]

Check your ground, make sure your NOT to a bolt. What do you have the speakers wire to?

 

[CrossoverOre 10+ year member]

disconnect speakers from amp, grab a dmm and check ohm load of speakers. Also check continuity to ground and make sure they are not grounding out.

 

[goingdef 10+ year member]

Check your ground, make sure your NOT to a bolt. What do you have the speakers wire to?

Why should you not use a bolt? every ground on my car is to a bolt has been for years and I have NEVER had an issue! and that's with a memphis 16-mc2000d and a T600.2 and both are bolted grounds as well as every wire on my charging system is also bolted versus running sheetmetal screws through the body.

 

[goingdef 10+ year member]

disconnect speakers from amp, grab a dmm and check ohm load of speakers. Also check continuity to ground and make sure they are not grounding out.

yep i would go with the ohm load being too low causing the amp to go protect when there's a fluctuation while playing at high levels, I had a T1000.1 that was only stable at 1ohm well I only had two choices with my subs 2ohm or 0.5 ohm well at 0.5 it would play until reaching 3/4 volume when it would go into protect. I would start there as well.

 

[CrossoverOre 10+ year member]

installers are taught not to connect to seat bolts. most vehicles have some to seal the threads or locktite to hold it in place. That prevents it from haveing a good ground unless you sand all the paint around the bolt. But I do see a lot of ppl on here saying no to bolts.

 

[BIGJEFF64 10+ year member]

Why should you not use a bolt? every ground on my car is to a bolt has been for years and I have NEVER had an issue! and that's with a memphis 16-mc2000d and a T600.2 and both are bolted grounds as well as every wire on my charging system is also bolted versus running sheetmetal screws through the body.

because some bolts today arent attached to solid metal grounding points to the vehicle this happens more with the unibody cars.

OP i would try to run a hole to under the truck and attach it to the frame see if that helps. only other thing i can think of is the ohm load is dropping too low and its cutting the amp out

 

[goingdef 10+ year member]

because some bolts today arent attached to solid metal grounding points to the vehicle this happens more with the unibody cars.
OP i would try to run a hole to under the truck and attach it to the frame see if that helps. only other thing i can think of is the ohm load is dropping too low and its cutting the amp out

well I guess if you just bolt to anything you can get a wrench on but if done right and each location is checked for proper connection with a dmm(which only takes a second per connection) there is no issue with using bolts.

 

[BIGJEFF64 10+ year member]

well I guess if you just bolt to anything you can get a wrench on but if done right and each location is checked for proper connection with a dmm(which only takes a second per connection) there is no issue with using bolts.

most of the beginners will look at u funny when u say get a DMM and check it and im sure they dont know what a good ground connection is

 

[snoopdan 5,000+ posts]

Its a feature of the amp.

 

[Radiospank 10+ year member]

i know this may sound nooby, but recently My sub speaker cables were touching inside my box causing my amp going into protect. I added proper connectors and attached them to the terminal cup with actual connectors vs jsut wrapping wire around it.. needles to say it works now btw im running DD m2a

 

[robertoyoung08 10+ year member]

maybe voltage is too low on ur amp and when u turn it up there isnt enough voltage being supplied to it so it goes into protect?

check votlage at the amp before/after you turn it up.

 

[jasonAz 10+ year member]

There are a few reasons why, on lower power amps its not as bad but high wattages its really bad because it creates a "floating ground type situation" and burns or blows up power supplies and mosfets. Sometimes the amp turns on but no output like a circuitry protection mode.

installers are taught not to connect to seat bolts. most vehicles have some to seal the threads or locktite to hold it in place. That prevents it from haveing a good ground unless you sand all the paint around the bolt. But I do see a lot of ppl on here saying no to bolts.

because some bolts today arent attached to solid metal grounding points to the vehicle this happens more with the unibody cars.
OP i would try to run a hole to under the truck and attach it to the frame see if that helps. only other thing i can think of is the ohm load is dropping too low and its cutting the amp out

 

[pro-rabbit 5,000+ posts]

Ground goes to the frame..not the chassis of the car.

 

[Falcons 5,000+ posts]

Ground goes to the frame..not the chassis of the car.

lies dustin you know you of all people know you ground to the plastic panels in your car.