Diagnostic Aids
WARNING: This page is about a different car, the 2002 Chevrolet Monte Carlo, 2002 Chevrolet Impala, 2001 Chevrolet Monte Carlo, and 2001 Chevrolet Impala. However, it is still accessible from the selected car via links, so may be relevant.
DTC U1301 indicates a short to ground or power in class 2 serial data line to a particular module. DTC U1301 will only be read as a history DTC. Check for intermittent connections and circuits by wiggling wires and connectors to suspect modules. See TEST C: SCAN TOOL DOES NOT COMMUNICATE WITH CLASS 2 DEVICE under SYSTEM TESTS to isolate intermittent condition.