Question about Rockford Fosgate Punch 301X Car Audio Amplifier
I was listening to the stereo i shut it off 30 min later i turned on and no sound. ihave power to the amp and the power light on the amp is on but no sound my question is there a internal fuse or something that burned out and can you open the amp to fix
There are many different ways that an amp can fail but the two most common failures are shorted output transistors and blown power supply transistors (< those are not blown). There are several types of protection circuits in amplifiers. The most common are over-current and thermal. The over-current protection is supposed to protect the output transistors. Sometimes it doesn't work well enough to prevent the failure of the output transistors but it will work well enough to shut the supply down before the power supply FETs are destroyed. If the amp remains in protect mode, goes into protect mode or blows the fuse as soon as the remote voltage is applied, shorted output transistors are almost certainly the cause. If the fuse protecting the amp is too large, if the protection circuit doesn't respond quickly enough or if the power supply is poorly designed, the power supply transistors may fail. If you see a lot of black soot on the power supply transistors (near the power transformer), the power supply transistors have failed. Soot on the board doesn't necessarily mean the transistors have failed. Sometimes, technicians don't clean up the mess from a previous failure.
In general, when a transistor fails, it will either short (common for output AND power supply transistors) or open (common for power supply transistors). Transistors act like valves. They control the current flowing through a circuit. A shorted transistor acts like a valve that's stuck open (passing too much current). In the case of an output transistor, the shorted transistors tries to deliver the full rail voltage to the speaker output terminal. If you've ever seen a damaged amp that pushed or pulled the speaker cone to its limits when the amp powered up (common on some Rockford amplifiers), that was almost certainly due to a shorted output transistor. When checking transistors, you most commonly look for shorted connections inside the transistor. You do this by using a multimeter to look for low resistance connections between the transistor's terminals.
I used the terms short and open on the previous paragraph. A short (short circuit) is a path through which current flows that should not be there. An open (open circuit) is a break in the circuit.
There are no internal fuses on any car audio Amplifier. Servicing will be required.
Posted on Dec 30, 2008
a 6ya expert can help you resolve that issue over the phone in a minute or two.
best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
the service is completely free and covers almost anything you can think of (from cars to computers, handyman, and even drones).
click here to download the app (for users in the US for now) and get all the help you need.
Posted on Jan 02, 2017
Tips for a great answer:
Aug 24, 2009 | Rockford Fosgate Car Audio & Video
Aug 22, 2009 | Rockford Fosgate Punch 401S Car Audio...
Jun 17, 2009 | Rockford Fosgate Punch 301X Car Audio...
Apr 13, 2009 | Rockford Fosgate P3001 Car Audio Amplifier
Mar 15, 2009 | Rockford Fosgate Punch 801S Car Audio...
Feb 04, 2009 | Rockford Fosgate Punch 401S Car Audio...
Jun 24, 2008 | Rockford Fosgate P3001 Car Audio Amplifier
Feb 20, 2008 | Rockford Fosgate Punch 301X Car Audio...
Sep 07, 2007 | Rockford Fosgate Punch 301X Car Audio...
Jan 22, 2017 | Alpine Car Audio & Video
249 people viewed this question
Usually answered in minutes!
Step 2: Please assign your manual to a product: