AC blows warm under load
 

2003 H2. Search isn't much help because AC is to short of a word as is air so here's my issue. AC blows fine when sitting or holding a speed but when I accelerate it blows warm until I reach whatever speed I'm going to be driving at then blows cold again. Any help is appreciated.

By design it will disengage the compressor clutch if RPM's are over 5250 (re-enable at 5000) or at wide open throttle (re-enable once let off). May or may not be what you are running into though....

You are probably low on refrigerant. I had the same issue yesterday and this morning I added a can and it seems to be fixed. It still did it but it was higher in the RPM range and like Mr. Knowledgeable (aka Mixmansc) said that is how it should function. Mixman was a big help with my problem yesterday and I’m glad he’s here to offer his help. We really need 12 more members just like him. I will added that I haven’t put my fender liners back in yet and there are two square sensors on the passenger side front and I think one might be a temperature sensor because last night my mirror read 143 degrees. I don’t know if this could have something to do with my issue or not but it was low on charge and when I drove it this morning it was cooler and reading 90 degrees.

maxjeep,

As I recall thet two square sensors on the passenger side (RHS) are actually two-wire negative-temperature-coefficient thermisters, one is for the HVAC and the other is for the inside mirror.

If you disconnect the mirror thermister it seems to take several hours before the display recovers the correct value, it seems to be a very long averaging cycle.

The Sunload Photo-Sensor (black dome on the dash) is monitored by the BCM and HVAC to compensate for increased cabin temperature cause by sunlight.

Be careful not to add refrigerant "ad-hoc", the H2 requires 1.6lbs of R134a, overfilling can put too much strain on the compressor, its better to get a specialist to drain the system and re-fill it with the correct amount, they will also add and compensate any lost PAG oil (speaking from experience here)