DTC U1064: Loss Of Serial Communications (PZM): Description
WARNING: This page is about a different car, the 1998 Cadillac DeVille. However, it is still accessible from the selected car via links, so may be relevant.
When ignition switch is in RUN position, all modules that communicate over the class 2 serial data bus send a State Of Health (SOH) message every 5 seconds to ensure system is operating properly. DTC will not set if DTC B1982, B1983 or U1300 is current. DTC U1064 will set when Memory Seat Module (MSM) does not receive an SOH message from PZM after 3 consecutive monitoring cycles. DTC U1064 will clear when MSM detects an SOH message from PZM, conditions for setting DTC no longer exists or upon every power mode initialization.
NOTE:
To identify circuit and components on class 2 serial data line, see appropriate wiring diagram under DATA LINK CONNECTORS in SYSTEM WIRING DIAGRAMS article.