Instruction: Answer the given question by extracting information from the supporting document.

Input:
Question: I have a 99 Grand Cherokee with the infinity system. Will this allow me to keep the infinity amp/speakers?
Document: I used this harness for my 2001 Jeep Grand Cherokee with the the Infinity system, to install an aftermarket stereo. It worked well, except for one thing. These Jeeps provide a separate ground wire that attaches to the back chassis of the original stereo. Because of this, these Metra harnesses do not include a ground wire connection. However, most aftermarket stereo harnesses do include a ground wire. What to do?
You wire (solder with shrink tubing [best] or crimp) the wires from this product to the new radio. You then plug this into the old harness that is part of the car.As for vehicles with the infinity system like mine, there is a 12ga black/yellow stripe wire that plugs directly to the radios negative/ground wire to get the radio/infinity amp to power up. As for vehicles like my 98 sebring lxi.
it WILL NOT work with the infinity sound system. I DONT CARE WHAT THE AD SAYS It DONT WORK, PERIOD
I used this to install a new high-end radio in an old Jeep Grand Cherokee. This harness worked perfectly and enabled me to keep the old radio and the old plug intact, so that I didn't have to cut the actual wiring of the car. This way I didn't have to solder anything in the little hole in the dash, but I could instead do all the soldering on a shop table, and then just plug and play, keeping all the hot, dangerous work away from my interior.
easier yet, if you're going to use new speakers too, just run new wiring all around and avoid the hassle. Might take longer, but more satisfying when you're done because you just built a whole new system. I never use stock unless I just want basic (sebring) but I went ALL after market on my saab (headrests, double din dvd, subs, speakers (had to bore out holes), and NO stock wiring...sounds better too
Just finished putting a new stereo in my 99 jeep cherokee and it worked great. The pre-stripped ends was pretty helpful too, took even less time than I was expecting.
I used to to install my Alpine in my '95 Jeep Grand Cherokee Laredo. It works great. I had to look up the diagram but once I found that all was good.
Harness was a perfect fit for my 97 grand cherokee. Just got a new radio I connected all the matching wires together and plugged it in, and the radio fired right up, no problems at all.
I used this Metra wiring harness also with a Metra single DIN installation kit to put a Pioneer head unit into a 1996 Jeep Grand Cherokee, worked perfect!! I highly recommend their products.
I bought this wiring harness in conjunction with the Metra 99-6000 Single DIN Installation Kit when I replaced the factory radio in my 1998 Jeep Cherokee Sport. It arrived within the estimated time frame and the materials appears to be as good as OEM. It made connecting the aftermarket head unit a fairly simple process. I would recommend this to others.
Answer: All I know is that on the 2001 it does you have to connect the amp on wire from your after market radio harness blue/white to the solid blue on this harness all other wires match perfect