Circuit Description
The brake pedal position (BPP) sensor is a potentiometer. The electronic brake control module (EBCM) supplies a 5-volt reference circuit and low reference circuit to the brake pedal position sensor. The brake pedal position sensor signal circuit is a direct input to the EBCM. The EBCM determines the brake pedal position based on the voltage from the brake pedal position sensor. The EBCM converts the brake pedal position sensor feed back voltage to a digital signal and puts it on the class 2 communication bus. If the voltage is greater than 4.9 volts, then DTC CO284 will set
Conditions for Running the DTC
| • | The EBCM control module must be powered. |
| • | This test is run continuously. |
Conditions for Setting the DTC
The feedback voltage is greater than 4.9 volts for more than 610 milliseconds.
Action Taken When the DTC Sets
When DTC C0284 is set the following will occur:
| • | The engine drive control is disabled. |
| • | The panic brake assist is disabled. |
| • | The traction control system is disabled. |
| • | The vehicle stability enhancement system is disabled. |
| • | The service vehicle soon lamp will illuminate. |
Conditions for Clearing the DTC
| • | The current DTC will clear when the fault is no longer present. |
| • | A history DTC clears after 100 consecutive ignition cycles in which no faults have occurred. |
| • | Clear the DTC with a scan tool. |
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
Schematic Reference: Interior Lights Schematics and Antilock Brake System Schematics in Antilock Brake System Connector End View Reference: Master Electrical Component List in Wiring Systems | ||||
1 | Did you perform the Lighting Systems Diagnostic System Check? | -- | Go to Step 2 | |
2 |
Is the BPP Sensor A/D Conversi parameter within the specified range? | 0.25-4.9 V | Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems | Go to Step 3 |
3 |
Does the scan tool indicate that the BPP sensor data parameter is less than the specified value? | 0.25 V | Go to Step 5 | Go to Step 4 |
4 | Test the low reference circuit of the BPP 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 9 | Go to Step 6 |
5 | Inspect for poor connections at the harness connector of the BPP 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 9 | Go to Step 7 |
6 | Inspect for poor connections at the harness connector of the electronic brake control module (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 9 | Go to Step 8 |
7 |
Important: Always perform the calibration procedure for the BPP sensor. Refer to Brake Pedal Position Sensor Calibration Description and Operation . Replace the BPP sensor. Refer to Brake Pedal Position Sensor Replacement . Did you complete the replacement? | -- | Go to Step 9 | -- |
8 |
Did you complete the replacement? | -- | Go to Step 9 | -- |
9 |
Does the DTC reset? | -- | Go to Step 2 | System OK |
