Chevrolet Trax: DTC U0020:Low speed can bus
Diagnostic Instructions
- Perform the Diagnostic System Check - Vehicle prior to using this
diagnostic procedure.
- Review Strategy Based Diagnosis for an overview of the diagnostic
approach.
- Diagnostic Procedure Instructions provides an overview of each
diagnostic category.
DTC Descriptors
DTC U0020
Low Speed CAN Bus
For symptom byte information, refer to Symptom Byte List .
Circuit/System Description
Devices connected to the GMLAN serial data circuits monitor for serial data
communications during normal
vehicle operation. Operating information and commands are exchanged among the
devices. The devices have
programmed information about what messages are needed to be exchanged on the
serial data circuits. The
messages are also supervised and some periodic messages are used by the receiver
device as an availability
indication of the transmitter device.
Conditions for Running the DTCs
- Supply voltage to the devices is in the normal operating range.
- The vehicle power mode requires serial data communication to occur.
- The DTC U2100 does not have a current status.
Conditions for Setting the DTC
A supervised periodic message that includes the transmitter device
availability has not been received
Action Taken When the DTCs Sets
The device uses a default value for the missing parameter.
Conditions for Clearing the DTC
- A current DTC clears when the malfunction is no longer present.
- A history DTC clears when the device ignition cycle counter reaches the
reset threshold, without a repeat
of the malfunction
Circuit/System Verification
Diagnosis of this DTC is accomplished via the symptom or an additional DTC.
Refer to Scan Tool Does Not
Communicate with Low Speed GMLAN Device, or Diagnostic Trouble Code (DTC) List -
Vehicle .
READ NEXT:
Diagnostic Instructions
Perform the Diagnostic System Check - Vehicle prior to using this
diagnostic procedure.
Review Strategy Based Diagnosis for an overview of the diagnostic
approach.
Diag
Diagnostic Instructions
Perform the Diagnostic System Check - Vehicle prior to using this
diagnostic procedure.
Review Strategy Based Diagnosis for an overview of the diagnostic
approach.
Diag
Diagnostic Instructions
Perform the Diagnostic System Check - Vehicle prior to using this
diagnostic procedure.
Review Strategy Based Diagnosis for an overview of the diagnostic
approach.
Diag
SEE MORE:
This vehicle has airbags. A rear
seat is a safer place to secure a
forward-facing child restraint. See
Where to Put the Restraint
Never put a rear-facing child seat in
the front. This is because the risk to
the rear-facing child is so great,
if the airbag deploys.
Warning
A child in a rear-facing ch
WARNING: Refer to Brake Fluid Irritant Warning .
CAUTION: Refer to Brake Fluid Effects on Paint and Electrical
Components Caution .
CAUTION: Only use products that comply with GM specifications and check
manufacturer information respectively. We recommend the use of GM
genuine products. Instruction