Anyone knows what this plug’s for in my 2.5Gen Montero?

[jorgeparty]

So I have a 99’ Mitsubishi Montero SR (Gen 2.5) (3.0L Engine) and I just pulled out this cover and found what looks to be a speaker base and behind it a big plug, which I don’t know what that’s for and I’m very curious to find out!

 

[plh]

no idea on the plug, but my '92 had speakers there. My '93 just had the holes, and speakers in the doors. The '92 did not have door speakers.

 

[nwoods]

The hole is for 4.5" speakers, but that connector is for something totally different, and no idea what. If it were on the left side, I'd be thinking car alarm or something, but there on the passenger side? I don't know.

 

[MummifiedCircuitry]

Pretty sure that's a tie in for the stereo harness, is yours missing the radio?

 

[jorgeparty]

Pretty sure that's a tie in for the stereo harness, is yours missing the radio?

Pretty sure that's a tie in for the stereo harness, is yours missing the radio?

My Montero only came with the two front door speakers and tweeters, the other two in the cargo area, and it regular radio. I replaced the OEM radio with a touch screen one and have a full sound system, all new speakers ( Alpine in front and pioneer in back), a 4 channel alplifier and a 10” Subwoofer.

Now that I think of it, didn’t a Montero come with a factory amp? (Infinity I’ve heard or something like that?) Could it be the amp’s plug?

 

[MummifiedCircuitry]

Yours may be different, is it like a Guam/PR spec? We didn't get 99 SR's here especially with a 3.0L, so some things will likely have differences. Some do have an amp, under a steel plate on the floor in the cargo area. Maybe someone ran new speaker wiring and removed the amp so that plug is not needed anymore. I think mine (97 SR) has a whole section of harness that runs off that plug and runs along that HVAC assembly you see in your last pic to the back of the head unit, yours doesn't appear to have that.

 

[Salonika]

That’s right by the ECM……looks like an ECM connector to me.