Helppppp

Is it ticking??!!!!111111BBBBBB

Antilock brake puter', I'd bet.

There isn't one in mine but they hadn't invented computers when mine was made. Maybe if you gave us the year, that might be helpful. Probably not. I don't think there was ever a computer under the back seat. Might could be the amplifier for the Infinity audio system? Kind of looks like a control module/computer of some sort, I think.

Factory amp for sound system.

Bet is says Infinity on it.

^ That would be my guess ^

wtf does this even mean? We're not mind readers (for the most part).

What led you to the forums to ask this question?

amp

Do you have a random antenna sticking out of the back left window? If so that would be the telephone box. I have a phone setup in my jeep and there is a black rectangular box under the back seat on the drivers side as that's what it is for.

If it's a limited XJ then it's an amp for stereo.

does it look like this?

Mine is a limited xj from 89. Look at the pic I posted of the box in mine

I think the OP just did a drive by and really doesn't have interest in an answer.

My guess is that it's a GPS tracking device put there by Homeland Security.

Mine has an ABS computer there.

Yeah, that definitely not an Infinity amp. Lol. That thing prob paired with a suitcase cell phone back in the day. Remember those?