DTC C1294 Brake Lamp Switch Circuit Always Active. Chevrolet Lumina 1999

For 1990-2009 cars only

Makes 🢒 Chevrolet 🢒 1999 🢒 Lumina 🢒 DTC 🢒 DTC C1294 Brake Lamp Switch Circuit Always Active

ABS Components
Antilock Brake System Schematics

Circuit Description

DTC C1294 determines the proper operation of the brake switch. Proper operation of the brake switch is important because the brake switch is an input used to determine when an ABS event is needed. The brake switch deactivates the ABS when the brake switch is off.

Conditions for Setting the DTC

DTC C1294 can set if the vehicle's speed is greater than 40 km/h (25 mph).

A malfunction exists if the brake was always on during two consecutive drive cycles.

Action Taken When the DTC Sets

•	A malfunction DTC stores.

•	ABS operation remains.

Conditions for Clearing the DTC

•	The condition responsible for setting the DTC no longer exists and the Scan Tool Clear DTCs function is used.

•	100 drive cycles pass with no DTCs detected.

Diagnostic Aids

The following conditions may cause an intermittent malfunction:

•	A poor connection

•	Rubbed-through wire insulation

•	A broken wire inside the insulation

•	A misadjusated brake switch

Use the enhanced diagnostic function of the Scan Tool in order to measure the frequency of the malfunction. Refer to the Scan Tool manual or Scan Tool Diagnostics located in this section for the procedure.

Thoroughly inspect any circuitry that may cause the intermittent complaint for the following conditions:

•	Backed out terminals

•	Improper mating

•	Improperly formed or damaged terminals

•	Poor terminal-to-wiring connections

•	Physical damage to the wiring harness

Step

Action

Value(s)

Yes

Was the Diagnostic System Check performed?

Go to Step 2

Go to Diagnostic System Check - ABS

Turn the ignition switch to the OFF position.
Verify that there is no pressure on the brake pedal.
Observe the rear brake lamps.

Are the rear brake lamps on?

Go to Step 3

Go to Step 5

Disconnect the stoplamp switch connector C1.

Are the rear brake lamps on?

Go to Step 8

Go to Step 4

Inspect the adjustment of the stoplamp switch.

Is the stoplamp switch adjusted correctly?

Go to Step 10

Go to Step 9

Disconnect the 24-way EBCM connector C1.
Turn the ignition switch to the ON position.

Do not start the engine.

Use the J 39200 in order to measure the voltage between the 24-way EBCM connector C1 terminal B9 and ground.

Is the voltage within the specified range?

0-2 V

Go to Step 6

Go to Step 8

Turn the ignition switch to the OFF position.
Inspect the 24-way EBCM connector C1 and the 24-way EBCM harness connector C1 for the following conditions:

•	Terminal damage

•	Poor terminal contact

•	Terminal corrosion

Is there evidence of poor terminal contact, terminal corrosion, or damaged terminals?

Go to Step 11

Go to Step 7

Reconnect the 24-way EBCM connector C1.
Install a scan tool.
Turn the ignition switch to the ON position, then Start the vehicle.
Test drive the vehicle obtaining a speed at least 40 km/h (25 mph).
Repeat the drive cycle, and steps 3,4, and 5 at least two additional times.
Use the scan tool in order to inspect for DTCs.

Does DTC C1294 set as a current DTC during the last three drive cycles?

Go to Step 12

Go to Step 13

Repair the short to voltage in CKT 17.

Is the repair complete?

Go to Diagnostic System Check - ABS

Adjust the stoplamp switch. Refer to Stop Lamp Switch Adjustment in Brakes.

Is the repair complete?

Go to Diagnostic System Check - ABS

Replace the stoplamp switch. Refer to Stop Lamp Switch Replacement in Brakes.

Is the repair complete?

Go to Diagnostic System Check - ABS

Replace all of the terminals and connectors that exhibit the following conditions:

•	Poor terminal contact

•

Corrosion

•	Damaged terminals

Is the repair complete?

Go to Diagnostic System Check - ABS

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

Is the repair complete?

Go to Diagnostic System Check - ABS

Is the malfunction intermittent or is not present at this time?

Go to Diagnostic Aids