Sight glass on 2002 T&C

If it had a sight glass it would be on the high side line between the condensor and evaporator. A sight glass isn't really useful for diagnosis of an A/C problem. Best way to check the freon is with a gauge set. Next best way is to run the A/C on coldest setting and see how cold it gets.

If I am using a thermometer to test the AC cooling capacity, what temperature am I looking for?

Thsi vehicle has no sight glass. The A/C manifold gauge set and thermometer is the way to do a performace check. Depending on ambient tem will determine what the evaporator temp will be.

Ambient Temperature 21° C

(70° F) 27° C

(80° F) 32° C

(90° F) 38° C

(100° F) 43° C

(110° F) Left Center Panel Outlet Discharge Air Temperature 1 to 8° C

(34 to 46° F) 3 to 9° C

(37 to 49° F) 4 to 10°C

(39 to 50° F) 6 to 11°C

(43 to 52° F) 7 to 18° C

(45 to 65° F) Discharge Pressure (High Side Service Port) 1034 to 1724 kPa

(150 to 250 psi) 1517 to 2275 kPa

(220 to 330 psi) 1999 to 2620 kPa

(290 to 380 psi) 2068 to 2965 kPa

(300 to 430 psi) 2275 to 3421 kPa

(330 to 450 psi) Suction Pressure (Low Side Service Port) 103 to 207 kPa

(15 to 30 psi) 117 to 221 kPa

(17 to 32 psi) 138 to 241 kPa

(20 to 35 psi) 172 to 269 kPa

(25 to 39 psi) 207 to 345 kPa

(30 to 50 psi)

Glenn Beasley Chrysler Tec

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Sight glasses are not used on R-134a systems, because bubbles can be present even when the system is fully charged. You HAVE to check with gauges and you HAVE to correct for the evaporator temperature once you read the gauge. There's no other way to properly service an R-134a system. There's a pressure vs. temperature curve chart in the AC section of every Factory Service Manual.