Air compressor not ff

Fuse 18 or 19

Fuse Box Diagram Jeep Wrangler (TJ; 1997-2006)

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The fuse panel is located behind the glove box. The location of the fuses in the passenger compartment: Jeep Wrangler (TJ; 1997. To access ...

1997-2006 Jeep Wrangler TJ Fuse Box Diagram

https://knigaproavto.ru > shemy > 920-1997-2006-jeep...
Oct. 8, 2019 - Fuse Box Diagram Jeep Wrangler engine: 2.4L, 2.5L and 4.0L (TJ; 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006)

Sounds like low flow issue. Flush and clean system, PROPERLY! Buy a flush kit, drain system, blow compressed air through, fill with cleaner/water mix, run for 30 min with heat on, drain system, blow out with compressed air, fill with water, run for 30 min, drain, blow out with compressed air, fill with 60% coolant mix.

Well this is different since most questions now are about no heat.
If one ac line is cold and the other is warm, I would suspect a blend door under the dash is not working. The blend doors direct air thru the heater core and the vents.

It could be bad blower motor

Hi:
You most likely have a partially blocked heater core, and at least it isn't leaking on the floor.

You might have sucess in trying to flush your cooling system, but often you end up replacing the heater core to fix the problem. Other possibilities are blockage of the air inlet on your heating system by leaves or other debris, but not likely in this case if you still have good air flow, but just not hot air.

The surge you are feeling is the a/c compressor engaging and dis engaging. the compressor places a demand on the horse power output of the engine which translates into surge feeling.

Have you recently changed / or added coolants? your Coolant system may need to bleed.

Run it for a while and check the two heater hoses to the fire wall for the heater core. Turn the heat inside on low and floor. The hoses (when the jeep is hot) should be about the same temp. One will be slightly cooler than the other one. If this is not the case and one is much colder than the other you have a plugged heater core. Mark the cool hose let the jeep completely cool remove the cold hose and the hot hose use a garden hose to flush the core in direction of the cold side to hot side. If this is not it you have a air pocket in the system or your blend doors in the air box under your dash are broke.

next time you go up a hill see if the heat is still blowing

This may be the AC compressor cycling switch is defective. It is located in the larger of the 2 AC lines coming from the compressor, it has a wire connector to it with 2-3 wires. To verify this is the issue jumper the connector with a small piece of wire and see if the compressor runs.