Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
---|---|---|---|---|
CAN Bus High Serial Data | U1500 | U2105-U2199 (U2142 or U2143 only) | U1500 | -- |
CAN Bus Low Serial Data | U1500 | U2105-U2199 (U2142 or U2143 only) | U1500 | -- |
CAN Bus High Terminated Serial Data | U1500 | U2105-U2199 (U2142 or U2143 only) | U1500 | -- |
CAN Bus Low Terminated Serial Data | U1500 | U2105-U2199 (U2142 or U2143 only) | U1500 | -- |
Modules connected to the CAN bus serial data circuits are high speed serial data modules that monitor for serial data communications during normal vehicle operation. Operating information and commands are exchanged among the modules. The modules have prerecorded information about what messages are needed to be exchanged on the serial data circuits. The messages are supervised and also, some periodic messages are used by the receiver module as an availability indication of the transmitter module. Each message contains the identification number of the transmitter module.
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 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 .
• | The system voltage is between 9-16 volts. |
• | The vehicle power mode master requires serial data communication to occur. |
A no communication condition exists on the CAN bus serial data for the EBCM.
• | The Vehicle stability Enhancement System (VSES), if equipped, and Traction Control System (TCS) will not function. |
• | System OFF lamps will illuminate for these systems. |
• | A current DTC clears when the malfunction is no longer present. |
• | A history DTC clears when the module ignition cycle counter reaches the reset threshold, without a repeat of the malfunction. |
• | An open on 1 CAN Bus circuit will not cause a U1500 DTC. |
• | If there are multiple non-communicating modules choose the one farthest from the EBCM. |
Master Electrical Component List
⇒ | If no data, repair the serial data circuits for a short to ground, short to voltage or an open/high resistance. If the circuits test normal, replace the steering wheel angle sensor. |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
• | Control Module References for module replacement, setup, and programming |