Circuit Description
This diagnostic trouble code (DTC) is used to determine when the electronic brake control module (EBCM) has lost the ability to provide rough road data to the control module for misfire detection (DTC P0300). When the control module detects this condition on the Class 2 Serial Data circuit, this DTC will be set.
Conditions for Running the DTC
| • | The vehicle speed is 1 mph (2 km/h) or more. |
| • | The engine speed is less than 5,800 RPM. |
| • | The engine load is less than 89 percent. |
Conditions for Setting the DTC
The VCM determines that the ABS system is unable to detect a rough road condition.
Action Taken When the DTC Sets
| • | The control module illuminates the malfunction indicator lamp (MIL) the first time the diagnostic runs and fails. |
| • | The control module will set the DTC and records the operating conditions at the time the diagnostic fails. The control module stores the failure information in the scan tools Freeze Frame/Failure Records. |
Conditions for Clearing the MIL or DTC
| • | The control module turns OFF the MIL after 3 consecutive drive trips when the test has run and passed. |
| • | A history DTC will clear if no fault conditions have been detected for 40 warm-up cycles. A warm-up cycle occurs when the coolant temperature has risen 22°C (40°F) from the startup coolant temperature and the engine coolant reaches a temperature that is more than 70°C (158°F) during the same ignition cycle. |
| • | Use a scan tool in order to clear the DTCs. |
Diagnostic Aids
Check for intermittent conditions.
An intermittent may be caused by any of the following conditions:
| • | A poor connection |
| • | Rubbed through wire insulation |
| • | A broken wire inside the insulation |
Thoroughly inspect any circuitry that is suspected of causing the intermittent complaint. Refer to Intermittent Conditions in Wiring Systems.
If a repair is necessary, refer to Wiring Repairs .
Test Description
Number(s) below refer to the step number(s) on the Diagnostic Table.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 |
Important: Before clearing the DTCs, use the scan tool Capture Info to save the Freeze Frame and Failure Records for reference. The control module's data is deleted once the Clear Info function is used. Did you perform the Powertrain On-Board Diagnostic (OBD) System Check? | -- | ||
Did you find a problem? | -- | Go to Diagnostic System Check In Antilock Brake System | ||
3 | Repair the circuit as necessary. Refer to Wiring Repairs . the action complete? | -- | -- | |
4 |
Does the scan tool indicate the diagnostic Passed? | -- | ||
5 | Does the scan tool display any additional undiagnosed DTCs? | -- | Go to the applicable DTC table | System OK |
