During an ABS event, the electronic brake control modulator (EBCM) calculates the total time that a dump valve is energized while attempting to unlock a locked wheel.
This diagnostic procedure supports the following DTCs:
DTC C0220-C0229 Antilock Brake System (ABS) Channel in Release Too Long
• | The ignition is ON. |
• | The vehicle is experiencing an ABS event. |
The total dump time for any dump valve has exceeded 9 seconds and the EBCM has not received a wheel speed signal from the corresponding wheel during this activity.
• | The EBCM disables the ABS/dynamic rear proportion (DRP). |
• | The ABS indicator turns ON. |
• | The brake warning indicator turns ON. |
The actions above are maintained during subsequent ignition cycles until the EBCM completes a power up self-test. This test concludes when the vehicle achieves a speed greater than 13 km/h (8 mph) and the wheel speeds are verified by the EBCM.
The Conditions for Setting the DTC are no longer present and you use the scan tool Clear DTCs function.
The most likely cause of this DTC is a mechanical failure that causes a wheel to lock and remain locked. The DTC may also set, conceivably, when the ABS is activated on surfaces that are nearly impossible to get traction on. If the DTC sets within these conditions, diagnosis of the ABS system is not necessary.
The number below refers to the step number on the diagnostic table.
Step | Action | Yes | No |
---|---|---|---|
1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | |
Do the solenoid tests show the system to be functioning normally? | Go to Diagnostic Aids | Go to Step 3 | |
3 | Replace the brake pressure modulator valve (BPMV). Refer to Control Module References . Did you complete the replacement? | Go to Step 4 | -- |
4 | Use the scan tool in order to perform the necessary solenoid tests. Do the solenoid tests show the system to be functioning normally? | System OK | Go to Step 3 |
During an ABS event, the electronic brake control module (EBCM) calculates the total time that a dump valve is energized while attempting to unlock a locked wheel.
This diagnostic procedure supports the following DTCs:
• | DTC C0220 Left Front Antilock Brake System (ABS) Channel in Release Too Long |
• | DTC C0221 Right Front Antilock Brake System (ABS) Channel in Release Too Long |
• | DTC C0228 Left Rear Antilock Brake System (ABS) Channel in Release Too Long |
• | DTC C0229 Right Rear Antilock Brake System (ABS) Channel in Release Too Long |
• | The ignition is ON. |
• | The vehicle is experiencing an ABS event. |
The total dump valve ON time for the left front brake circuit has exceeded 9 seconds and the EBCM has not received a wheel speed signal from the left front wheel during this activity.
The total dump valve ON time for the right front brake circuit has exceeded 9 seconds and the EBCM has not received a wheel speed signal from the right front wheel during this activity.
The total dump valve ON time for the left rear brake circuit has exceeded 9 seconds and the EBCM has not received a wheel speed signal from the left rear wheel during this activity.
The total dump valve ON time for the right rear brake circuit has exceeded 9 seconds and the EBCM has not received a wheel speed signal from the right rear wheel during this activity.
• | The EBCM disables the ABS/dynamic rear proportion (DRP). |
• | The ABS indicator turns ON. |
• | The brake warning indicator turns ON. |
The actions above are maintained during subsequent ignition cycles until the EBCM completes a power up self-test. This test concludes when the vehicle achieves a speed greater than 13 km/h (8 mph) and the wheel speeds are verified by the EBCM.
The Conditions for Setting the DTC are no longer present and you use the scan tool Clear DTCs function.
The most likely cause of this DTC is a mechanical failure that causes a wheel to lock and remain locked. The DTC may also set, conceivably, when the ABS is activated on surfaces that are nearly impossible to get traction on. If the DTC sets within these conditions, diagnosis of the ABS system is not necessary.
The number below refers to the step number on the diagnostic table.
Step | Action | Yes | No |
---|---|---|---|
1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | |
Do the solenoid tests show the system to be functioning normally? | Go to Diagnostic Aids | Go to Step 3 | |
3 | Replace the brake pressure modulator valve (BPMV). Refer to Control Module References . Did you complete the replacement? | Go to Step 4 | -- |
4 | Use the scan tool in order to perform the necessary solenoid tests. Do the solenoid tests show the system to be functioning normally? | System OK | Go to Step 3 |