DTC C1216 EBCM Commanded Pressure Release Too Long. Buick GL7 (Export) 2000

For 1990-2009 cars

### Circuit Description

The EBCM monitors the On/Off state of each solenoid and recognizes when the ABS is in pressure decrease too long. This fault indicates that the EBCM was unable to decrease brake pressure enough to a certain wheel to prevent excessive wheel slip.

### Conditions for Running the DTC

• | The ABS is active.

• | The wheel speed is less than 5 km/h (3 mph).

### Conditions for Setting the DTC

The solenoid of the wheel is releasing for greater than 1 second.

### Action Taken When the DTC Sets

• | The EBCM disables the ABS for the duration of the ignition cycle.

• | The ABS indicator turns ON.

### Conditions for Clearing the DTC

• | The condition for the DTC is no longer present and the DTC is cleared with a scan tool.

• | The electronic brake control module (EBCM) automatically clears the history DTC when a current DTC is not detected in 100 consecutive drive cycles.

### Diagnostic Aids

Possible causes of this DTC are the following conditions:

• | A contaminated hydraulic unit.

• | An intermittent wheel speed sensor.

• | A sticking solenoid.

• | Excessive brake drag or high resistance in base brake system.

• | Suspension system irregularities.

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
Schematic Reference: Antilock Brake System Schematics
1 | Did you perform the ABS Diagnostic System Check? | -- | Go to Step 2 | Go to Diagnostic System Check - ABS

2

1. Install a scan tool.
2. Turn ON the ignition, with the ignition OFF.
3. With a scan tool, observe the DTC Information parameter in the ABS Diagnostic Trouble Codes (DTCs).

Does the scan tool display any other ABS DTCs relating to wheel speed sensor or solenoid valve operation?

--

Go to Diagnostic Trouble Code (DTC) List/Type

Go to Step 3

3 | With a scan tool, monitor all of the wheel speed sensor in the ABS Data Display while decelerating the vehicle from 56 to 0 km/h (35 to 0 mph). Do any of the wheel speeds indicate erratic or intermittent operation? | -- | Go to Diagnostic Trouble Code (DTC) List/Type for Excessive Wheel Speed Variation for the affected wheel | Go to Step 4

4

Inspect the base brake system for the following conditions:

• | Brake fluid contamination.

• | Excessive brake drag.

• | Suspension system irregularities.

Did you find and correct the condition?

--

Go to Step 7

Go to Step 5

5

1. Use the scan tool in order to clear the DTCs.
2. With the scan tool, perform the Automated Test.

Does the DTC reset as a current DTC?

--

Go to Step 6

System OK

6 | Replace the BPMV. Refer to Brake Pressure Modulator Valve Replacement . Did you complete the repair? | -- | Go to Step 7 | --

7

1. Use the scan tool in order to clear the DTCs.
2. With the scan tool, perform the Automated Test.

Does the DTC reset?

--

Go to Step 2

System OK