Our 1997 TSI Grand Cherokee air conditioner is leaking in the passenger side. How do we fix it?

You preliminary diagnostic about leak is hafl correct, but this is of a clogged A/C drain hose. It's a very common thing to happen. Here some details:

If your vehicle has an A/C drain hose, it will be located on the engine side of the firewall, below where the two A/C lines go through the firewall.

NO: 24-18-94
GROUP: Heating & A/C
DATE: Nov. 18, 1994
SUBJECT: Condensate Drain Tube Eliminated


MODELS:
1994-1995 (AN) Dakota
1993-1995 (XJ) Cherokee


DISCUSSION: The above vehicles no longer use an air conditioner condensate drain tube. Cherokee's built after September 3, 1993 (MDH 09-03-xx) and Dakota's built after June 1, 1994 (MDH 06-01-xx) no longer need the condensate drain tube. Do not install in the field or submit a shortage and error request.

Somewhere just below the Suction and Liquid Lines you will see a small black hose coming through the firewall and pointing down. This is the A/C drain hose. Take a piece of wire and snake out the hose. This will clear the blockage and allow the water to drain out.

You may have to remove the drain hose completely. If so, it just pulls right out and you can slip it back on easily enough.

Also, in this link could find other details with images: Condensate Drain on Jeep Grand Cherokee

Hope this helps to solve it (remember to rate and comment this free answer).

If by leaking, you mean there is a puddle of water under the passenger side, (under the engine when parked) then that is normal. Nothing needs to be fixed. If you mean some other kind of leaking please repost and explain more about where and what is leaking.
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