GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Buick 🢒 2002 🢒 LeSabre 🢒 Brakes 🢒 Antilock Brake System 🢒 DTC C1295

Circuit Description

The electronic brake control module (EBCM) sources 5 volts on the stop lamp switch signal circuit when the stop lamp switch is inactive. The voltage is supplied a ground path through the stop lamp bulbs.

Conditions for Running the DTC

The ignition is ON.

Conditions for Setting the DTC

The stop lamp switch input voltage is between 2.1 volts and 5.3 volts for 2 seconds.

Action Taken When the DTC Sets
    • The EBCM disables the TCS for the duration of the ignition cycle.
    • The Traction Off indicator turns ON.
    • The ABS 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

Possible causes of this DTC are the following conditions:

    • A signal circuit of the stop lamp switch is open.
    • The stop lamp switch is misadjusted.
    • Verify proper stop lamp switch operation using the data list of the scan tool. As the brake is applied, the data list displays the stop lamp switch ON within 2.54 cm (1 in) of travel.
    • All brake lamps are open.
    • All brake lamp grounds are open.
    • Circuit has a wiring problem, terminal corrosion, or poor connections.
    • Loose or corroded EBCM ground or ECM ground.
    • An internal EBCM problem.

Test Description

The numbers below refer to the step numbers on the diagnostic table.

  1. This DTC detects an open stop lamp switch signal circuit from the stoplamp side of the splice pack to the EBCM.

    2.

  2. Verifies that the stop lamps are operating properly.

Step

Action

Yes

No

Schematic Reference: Antilock Brake System Schematics

Connector End View Reference: Antilock Brake System Connector End Views

1

Did you perform the ABS Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - ABS

2
  1. Press the brake pedal.
  2. With the scan tool, observe the Stop Lamp Switch parameter in the DRP/ABS/TCS data list.

Does the Stop Lamp Switch parameter display Applied?

Go to Step 4

Go to Step 3

3

Test the signal circuit of the stop lamp switch for an open or high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 7

Go to Step 5

4

Press the brake pedal.

Are all of the stop lamps ON?

Go to Step 5

Go to Stop Lamps Inoperative

5

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 7

Go to Step 6

6

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 7

--

7
  1. Use the scan tool in order to clear the DTCs.
  2. 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