OBD-II Generic Error Code U1064: How to Fix It (GM BCM Communication Loss)

Q: Can I drive my GM vehicle with a U1064 code?

In many cases, yes — your vehicle may still start and drive with U1064 active. However, BCM communication loss can disable important functions like power locks, interior lighting, the security system, or climate controls. In some situations it can also affect transmission shifting or other powertrain-related communication. It is best to diagnose and repair the fault promptly rather than continuing to drive indefinitely with the code active.

Q: Will a dead or weak battery cause a U1064 code?

Yes. A low or failing battery is one of the most common causes of U1064 and other U-code network faults on GM vehicles. When battery voltage drops below the minimum operating threshold, modules can temporarily lose communication with each other. Always test and load-check the battery as your very first diagnostic step before investigating wiring or modules.

Q: What GM vehicles commonly get error code U1064?

U1064 has been reported across a wide range of GM platforms including Chevrolet Silverado, Tahoe, Suburban, Malibu, Equinox, and Traverse; GMC Sierra, Yukon, and Acadia; Buick Enclave and LaCrosse; and Cadillac Escalade models. It is particularly common on vehicles from the late 1990s through the mid-2010s that use GM's GMLAN or Class 2 communication network.

Q: Can I replace the BCM myself without programming?

Physically installing a BCM is within reach for a DIY mechanic, but the programming step is not optional on GM vehicles. An unprogrammed or improperly programmed BCM will not communicate correctly with the engine control module, transmission, security system, and other modules. Without programming, the vehicle may not start at all. BCM programming requires a factory-level GM diagnostic tool (GDS2 or Tech 2), so unless you have access to that equipment, BCM replacement should be handed off to a professional.

Q: Could another module be causing the U1064 code — not the BCM itself?

Absolutely. U1064 indicates that another module (such as the ECM, TCM, or instrument cluster) is reporting it cannot communicate with the BCM — but the BCM is not necessarily the failed component. The fault could lie in the CAN bus wiring between modules, a bad ground, a corroded connector, or even a different module that is dragging down the network. Always diagnose the full communication network before assuming the BCM needs replacement.

Abstract

Error code U1064 is a network communication fault indicating that one or more modules in your GM vehicle have lost contact with the Body Control Module (BCM). The BCM is responsible for managing key electrical systems like power windows, door locks, lighting, and security, so when communication breaks down, multiple features may stop working simultaneously. This code is classified as medium severity — your vehicle may still be drivable, but it should be diagnosed and repaired promptly to prevent further electrical or safety issues.