DTC P1460: Wot A/C Control Circuit Malfunction & P1464: A/C Demand Out Of Range: Condition

WARNING: This page is about a different car, the 2002 Mazda 626. However, it is still accessible from the selected car via links, so may be relevant.

DTC P1460 is set when Powertrain Control Module (PCM) detects input voltage from A/C relay does not change with A/C on and engine at Wide Open Throttle (WOT); CDCV is to high or to low. DTC P1464 is set when Powertrain Control Module (PCM) detects input voltage from A/C relay does not change while KOER self-test is being preformed. Possible causes are:

A/C relay malfunction.
Short or open circuit between A/C relay and PCM.
Open circuit between fuse and A/C relay.
PCM malfunction.