DTC PZ2152, Loss Of Serial Communications - HVAC Programmer: Notes

WARNING: This page is about a different car, the 1996 Cadillac Seville and 1996 Cadillac DeVille. However, it is still accessible from the selected car via links, so may be relevant.

Every 5 seconds, while ignition switch is in RUN position, control modules that communicate on class 2 data bus transmit a performance condition signal to Heating, Ventilation and Air Conditioning (HVAC) programmer indicating system is operating properly. Signal is then transmitted to PZM. DTC PZ2152 will set when PZM does not receive signal from HVAC programmer after 3 consecutive monitoring cycles. When DTC PZ2152 is set, PZM will send a class 2 signal to instrument panel cluster to display NO ACM DATA message. DTC PZ2152 will clear when HVAC programmer transmits signal to PZM.

If multiple class 2 codes are set as current (i.e., PZ2016, PZ2096, PZ2128, PZ2152, PZ2153), check for short to ground or battery in circuit between HVAC programmer and individual control modules.