03 Astro -A/C high doesnt work.

[Spectt]

Hey Guys,
Im a newbie here but I figured if anyone can help with my issue would be on here.
My husband and I own a 03 Astro Cargo that we use daily for our courier delivery business. We are in the van for 8-10 hours daily and now its real hot out , we are stuck with no HIGH setting on our A/C.
Our first remedy we had the blower /motor and fan resistor replaced. This didnt work.
NEXT, we replaced the resistor and the connection that it plugs into. The connection had had burn marks in it so we had replaced that also. That whole system is replaced.
Then, we bought two cans to recharge our system so at least the other 3 settings would be more cooler because we dont have High.
Now, sometimes we turn a hard left, we hear something (a fan) blow way harder than its usual. Then it pumps way mpre hard cool air out, but it only lasts for a few moments.
Pleae anything you can recommend would be appreciated. Thanks

[shorod]

The High blower speed setting is powered by the Orange wire at the blower motor resistor at terminal B. This triggers a relay that appears to be part of the blower motor resistor assembly. The blower motor High relay also requires power on the Orange wire at terminal location A which is fed from 30A fuse K9 in the underhood fuse box, as well as a good ground at blower motor resistor terminal location C (black wire).


If you have battery power on the two orange wires and good ground at the black wire, the issue would either need to be the blower motor relay, the blower motor itself (unlikely since it works on slower speeds) or an issue in the wiring of the blower motor resistor assembly.


-Rod

[brcidd]

The increased sound (and volume of air flow) you hear/feel while rounding corners is most likely due to a vacuum leak. The recirc air door is driven by vacuum, and when vacuum is not adequate, the door will close and the air path is more restricted and longer as it sucks in outside air instead of the shortcut to inside air. You are hearing the increase and decrease of air volume as the door opens and closes. Also, the mode doors will be affected, and air flow can be diverted to defrost, as vacuum comes and goes. Find and fix vacuum lines- most likely at underhood vacuum reservoir or at intake manifold source connection. - look for brittle heat baked black plastic and crumbly rubber connections on intake manifold right behind a/c compressor. Hard to get to, but you can feel the way around....

Yes, your blower relay is highly suspect, the burn marks you saw on the terminal at the blower motor are probably also present internal to the relay contacts. There might even be melted plug/terminal right at the relay as you saw on the blower motor. A quick inspection would be in order. Astros are notorious for blower motor wiring overheating at the connections issues. Napa sells the new wiring harnesses that can be spliced in to replaced the brittle, melted terminals you are . likely to encounter. The relay is built into the resistor module, so since you replaced that, the wiring terminals are the next thing I'd consider.