Q: How to Replace the Desiccant in an Automotive Air Conditioning System?A: Detach the cable from the negative battery terminal, remove the condenser, using an Allen wrench, detach the end plug, and remove the desiccant from the condenser with a pair of needle-nose pliers. Use new 0-rings and a new bottom cap when installing the new desiccant, tighten the end plug, and lubricate the 0-rings with R-134a compatible refrigerant. Installation is the reverse of removal, have the system evacuated, charged, and leak-tested.