2010 Cadillac CTS Sedan AWD V6-3.0L Page 2051
DTC U1826 or U1827
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System
Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Strategy Based Diagnosis) for an
overview of the diagnostic approach.
* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure
Instructions) provides an overview of each diagnostic category.
DTC Descriptor
DTC U1826 71
- Lost Communication With Multi-Axis Acceleration Sensor Module on Bus "B" Invalid Serial Data Received
DTC U1826 72
- Lost Communication With Multi-Axis Acceleration Sensor Module on Bus "B" Alive Counter Incorrect/Not Updated
DTC U1826 7F
- Lost Communication With Multi-Axis Acceleration Sensor Module on Bus "B" Erratic
DTC U1827 71
- Lost Communication With Steering Angle Sensor Module on Bus "B" Invalid Serial Data
DTC U1827 72
- Lost Communication With Steering Angle Sensor Module on Bus "B" Alive Counter Incorrect/Not Updated
DTC U1827 74
- Lost Communication With Steering Angle Sensor Module on Bus "B" Value of Signal Protection Calculation Incorrect
DTC U1827 7F
- Lost Communication With Steering Angle Sensor Module on Bus "B" Erratic
Diagnostic Fault Information
Circuit/System Description
The electronic brake control module (EBCM) activates the other modules connected to the CAN serial data circuits by applying voltage when the
ignition key is in ACC, ON or START. The EBCM, Yaw Rate Sensor, and the Steering Angle or Steering Wheel Position Sensor are the only
modules connected to the CAN bus serial data circuits. For more information on CAN bus serial data refer to Data Link Communications
Description and Operation (See: Powertrain Management/Computers and Control Systems/Information Bus/Description and Operation).
Conditions for Running the DTC
* Ignition is On, the system voltage is between 9-16 volts.
* The vehicle power mode master requires serial data communication to occur.
