Circuit Description
The controller area network (CAN) circuits provide a communication network between the electronic brake control module (EBCM), steering wheel position sensor, yaw rate sensor, and the data link connector (DLC).
DTC Descriptors
This diagnostic procedure supports the following DTCs:
| • | DTC U0123 Yaw Rate Circuit Malfunction |
| • | DTC U0124 CAN Bus Communication |
Conditions for Running the DTC
DTC U0123 and U0124 can be set anytime the ignition switch is in the ON position.
Conditions for Setting the DTC
The EBCM does not receive data from the yaw rate sensor.
Action Taken When the DTC Sets
| • | The Antilock Brake System (ABS) warning indicator turns ON. |
| • | The vehicle stability control (VSC) warning indicator turns ON. |
| • | The VSC and traction control is disabled. |
Conditions for Clearing the DTC
The condition responsible for setting the DTC no longer exists and the scan tool Clear DTCs function is used.
Diagnostic Aids
Thoroughly inspect the wiring and the connectors. An incomplete inspection of the wiring and the connectors may result in a misdiagnosis, causing a part replacement with the reappearance of the malfunction.
The following are possible causes of the malfunction:
| • | An open or high resistance in the yaw rate sensor ground circuit |
| • | An open, high resistance, or short to ground in the yaw rate sensor ignition voltage circuit |
| • | A yaw rate sensor malfunction |
If an intermittent malfunction exists, refer to Testing for Intermittent Conditions and Poor Connections .
Test Description
The numbers below refer to the step numbers on the diagnostic table.
-
This step tests the yaw rate sensor ground circuit for an open or high resistance.
-
This step tests the yaw rate sensor ignition voltage circuit for an open, high resistance, or short to ground.
Step | Action | Value(s) | Yes | No | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
Schematic Reference: Antilock Brake System Schematics Connector End View Reference: Antilock Brake System Connector End Views | ||||||||||
1 | Did you perform the Diagnostic System Check - Vehicle? | -- | Go to Step 2 | |||||||
2 |
Is the resistance as specified? | 54-69 ohms | Go to Step 3 | Go to Step 5 | ||||||
Test the steering wheel position sensor ground circuit for an open or high resistance. Did you find and correct the condition? | -- | Go to Step 7 | Go to Step 4 | |||||||
Test the steering wheel position sensor ignition voltage circuit for the following:
Did you find and correct the condition? | -- | Go to Step 7 | Go to Step 6 | |||||||
5 | Locate and repair open, high resistance, or short in the CAN - high or CAN - low circuits of the yaw rate sensor. Did you complete the repair? | -- | Go to Step 7 | -- | ||||||
6 | Replace the yaw rate sensor. Refer to Vehicle Yaw Sensor Replacement . Did you complete the replacement? | -- | Go to Step 7 | -- | ||||||
7 |
Does the DTC reset? | -- | Go to Step 2 | System OK | ||||||
