DTC C1282. Buick LeSabre 2001

For 1990-2009 cars only

Makes 🢒 Buick 🢒 2001 🢒 LeSabre 🢒 Brakes 🢒 Antilock Brake System 🢒 DTC C1282

Circuit Description

The vehicle stability enhancement system (VSES) is activated by the electronic brake control module (EBCM) calculating the desired yaw rate and comparing it to the actual yaw rate input. The desired yaw rate is calculated from measured steering wheel position, vehicle speed, and lateral acceleration. The difference between the desired yaw rate and actual yaw rate is the yaw rate error, which is a measurement of oversteer or understeer. If the yaw rate error becomes too large, the EBCM will attempt to correct the vehicle yaw motion by applying differential braking to the left or right front wheel.

Conditions for Running the DTC

The EBCM performs 6 different tests to detect a DTC condition. The numbers below correspond to the numbers in Conditions for Setting the DTC.

The yaw rate sensor bias test runs with the ignition ON.
The yaw rate sensor acceleration test runs with the ignition ON.
The yaw rate sensor circuit test runs with the vehicle stopped or with the vehicle speed greater than 45 km/h (28 mph).
The yaw rate isolation test runs with the following conditions:

•	The brake pedal is not pressed.

•	The ABS is not active.

•	The vehicle speed is greater than 5 km/h (3 mph).

The above yaw rate isolation test run with the VSES active.
The false activation test runs with the VSES active.

Conditions for Setting the DTC

The EBCM performs 6 different tests to detect a DTC condition. The numbers below correspond to the numbers in Conditions for Running the DTC.

The yaw rate bias is greater than 7 degrees/second.
The yaw rate input change is greater than 390 degrees/second/second.
The yaw rate input voltage is less than 0.15 volts or greater than 4.85 volts for 1 second.
The yaw rate error is greater than 10 degrees/second 30 times within a drive cycle.
The yaw rate error is greater than 10 degrees/second for 5 seconds. Under this condition, this DTC will set along with DTC C1281.
The yaw rate error is greater than 10 degrees/second with the vehicle speed less than 60 km/h (37 mph) and the acceleration pedal is pressed more than 25 percent of the pedal travel range for 1 second during the VSES activation. Under this condition, this DTC will set along with DTC C1281.

Action Taken When the DTC Sets

•	The EBCM disables the VSES for the duration of the ignition cycle.

•	The DIC displays the Service Stability System message.

•	The ABS/TCS remains functional.

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

The following conditions can cause this concern:

•	Improper steering alignment.

•	Open, short to ground, or short to voltage.

•	Internal lateral accelerometer failure.

•	EBCM internal failure.

Test Description

The number below refers to the step number on the diagnostic table.

Tests for the proper operation of the circuit in the low voltage range.

Tests for the proper operation of the circuit in the high voltage range. If the fuse in the jumper opens when you perform this test, the signal circuit is shorted to ground.

Tests for a short to voltage in the 5 volt reference circuit.

Tests the bias voltage of the yaw rate sensor.

Step

Action

Values

Yes

Schematic Reference: Antilock Brake System Schematics

Connector End View Reference: Antilock Brake System Connector End Views

Did you perform the ABS Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - ABS

Install a scan tool.
Turn ON the ignition, with the engine OFF.
With a scan tool, observe the Yaw Rate Sensor Input parameter in the VSES data list.

Does the scan tool display that the Yaw Rate Sensor Input parameter is within the specified range?

0.15-4.85 V

Go to Step 6

Go to Step 3

Turn OFF the ignition.
Disconnect the yaw rate sensor connector.
Turn ON the ignition, with the engine OFF.
With the scan tool, observe the Yaw Rate Sensor Input parameter.

Does the scan tool display that the Yaw Rate Sensor Input parameter is less than the specified value?

0.15 V

Go to Step 4

Go to Step 10

Turn OFF the ignition.
Connect a 3 amp fused jumper wire between the 5 volt reference circuit of the yaw rate sensor and the signal circuit of the yaw rate sensor.
Turn ON the ignition, with the engine OFF.
With the scan tool, observe the Yaw Rate Sensor Input parameter.

Does the scan tool display that the Yaw Rate Sensor Input parameter is greater than the specified value?

4.85 V

Go to Step 5

Go to Step 8

Disconnect the fused jumper wire.
Measure the voltage between the 5 volt reference circuit of the yaw rate sensor and the low reference circuit of the yaw rate sensor.

Does the voltage measure between the specified range?

4.85-5.2 V

Go to Step 12

Go to Step 7

Does the scan tool display that the Yaw Rate Sensor Input parameter is within the specified range?

2.3-2.7 V

Go to Diagnostic Aids

Go to Step 11

Test the 5 volt reference circuit of the yaw rate sensor for a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 16

Go to Step 13

Test the 5 volt reference circuit of the yaw rate sensor for the following conditions:

•

An open

•	A short to ground

•	A high resistance

Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 16

Go to Step 9

Test the signal circuit of the yaw rate sensor for the following conditions:

•

An open

•	A short to ground

•	A high resistance

Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 16

Go to Step 13

Test the signal circuit of the yaw rate sensor for a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 16

Go to Step 13

Important: Removing battery voltage or ground from the EBCM will result in the following conditions:

•	Loss of the TIM learned tire inflation configuration parameters in the EBCM

•	The EBCM sets DTC C1245.

When the diagnosis is complete, inspect the tire pressures and perform the TIM reset. Refer to Tire Pressure Monitor Procedure in Tire Pressure Monitoring.

Disconnect the EBCM harness connector.
Install the J 39700 Universal Pinout Box using the J 39700-300 Cable Adapter to the EBCM harness connector only.
Test the low reference circuit of the yaw rate sensor for a high resistance or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 16

Go to Step 12

Inspect for poor connections at the harness connector of the yaw rate sensor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 16

Go to Step 14

Inspect for poor connections at the harness connector of the EBCM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 16

Go to Step 15

Replace the yaw rate sensor. Refer to Vehicle Yaw Sensor Replacement .

Did you complete the repair?

Go to Step 16

Important: Perform the setup procedure for the EBCM. An unprogrammed EBCM will result in the following conditions:

•	Inoperative or poorly functioning system operations

•	The EBCM sets DTC C1248 and DTC C1255m3.

Replace the EBCM. Refer to Electronic Brake Control Module Replacement .

Did you complete the repair?

Go to Step 16

Clear the DTCs using the scan tool.
Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.

Does the DTC reset?

Go to Step 2

System OK