Circuit Description
DTC C1295 identifies open brake switch circuitry that prevents the brake switch input to the EBCM from changing states while applying the brake.
This DTC is used in conjunction with DTCs C1291 and C1292 to determine the cause of an open stoplamp switch malfunction.
Conditions for Setting the DTC
| • | DTC C1295 can set after initialization is complete. |
| • | A malfunction exists if the brake switch input voltage is out of specification for one second. An open circuit exists when the brake switch input voltage is out of specification. |
Action Taken When the DTC Sets
| • | A malfunction DTC stores. |
| • | ABS disables. |
| • | The ABS warning indicator turns ON. |
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. A drive cycle consists of starting the vehicle, driving the vehicle over 16 km/h (10 mph), stopping and then turning the ignition OFF. |
Diagnostic Aids
The following conditions may cause a malfunction:
| • | A poor connection |
| • | Rubbed-through wire insulation |
| • | A broken wire inside the insulation |
| • | Faulty (open) stoplamp switch electrical circuit |
| • | All brake lamp bulbs are open |
| • | Faulty stoplamp bulb electrical circuit (open/high resistance to ground) |
Use the enhanced diagnostic function of the Scan Tool in order to measure the frequency of the malfunction.
Thoroughly inspect any circuitry that may cause the intermittent complaint for the following conditions:
| • | Backed out terminals |
| • | Improper mating |
| • | Broken locks |
| • | Improperly formed or damaged terminals |
| • | Poor terminal-to-wiring connections |
| • | Physical damage to the wiring harness |
Test Description
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This test determines if the EBCM is receiving a brake switch input signal.
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This test checks for an open in the brake switch input circuit.
Step | Action | Value(s) | Yes | No | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
1 | Was A Diagnostic System Check-ABS performed? | -- | Go to Step 2 | |||||||
2 |
Are the rear brake lamps ON? | -- | Go to Step 3 | Go to Step 6 | ||||||
Do not start the engine. Does the Scan Tool indicate that the brake switch is ON within 25 mm (1.0 inch) of the brake pedal travel? | -- | Go to Step 10 | Go to Step 4 | |||||||
Do not start the engine. Is the voltage equal to or greater than the specified voltage? | 10 V | Go to Step 5 | Go to Step 7 | |||||||
5 | Inspect the EBCM connector and the EBCM harness connector for the following conditions:
Are poor terminal contact, terminal corrosion or damaged terminals evident? | -- | Go to Step 8 | Go to Step 9 | ||||||
6 | Repair the open brake lamp circuit wiring. Refer to Exterior Lights System Check in Lighting Systems for diagnosis. Is the repair complete? | -- | -- | |||||||
7 | Repair the open or high resistance in the GRN/WHT wire between the stop lamp switch and the EBCM. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | -- | |||||||
8 | Replace all the terminals or the connectors that exhibit the following conditions:
Refer to Connector Repairs in Wiring Systems. Is the repair complete? | -- | -- | |||||||
9 | Replace the EBCM. Refer to Electronic Brake Control Module Replacement . Is the repair complete? | -- | -- | |||||||
10 | The malfunction is intermittent or is not present at this time. Refer to Diagnostic Aids for more information. Is the action complete? | -- | System OK | -- |
