hispls 5,000+ posts
CarAudio.com Veteran
I don't think any amplifier built in the last 20 years would be broken and not have a protect or fault light come up. Even the Alpine amps 30 years ago had protect/fault LEDs.
Likely there is a wiring problem somewhere and depending on your DMM and conditions when you measure a sub reading 2 ohm or whatever on a 4 ohm coil may not mean anything except you had a door open and it was a windy day or your DMM isn't terribly accurate. A broken sub will have either a coil that reads infinity Ohms (open) or will read normal impedance but make bad noises while playing or if you try to move the cone by hand.
I do NOT believe the woofer is the problem nor the amp.
Likely there is a wiring problem somewhere and depending on your DMM and conditions when you measure a sub reading 2 ohm or whatever on a 4 ohm coil may not mean anything except you had a door open and it was a windy day or your DMM isn't terribly accurate. A broken sub will have either a coil that reads infinity Ohms (open) or will read normal impedance but make bad noises while playing or if you try to move the cone by hand.
I do NOT believe the woofer is the problem nor the amp.