DTC PZ2016, Loss Of Serial Communications - Pcm: 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 Powertrain Control Module (PCM), indicating system is operating properly. Signal is then transmitted to PZM. DTC PZ2016 will set when PZM does not receive signal from PCM after 3 consecutive monitoring cycles. DTC PZ2016 will clear when PCM 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 PCM and individual control modules.