The EBCM uses the BPP Sensor to determine if an extended brake travel event has occured. If an extended brake travel condition exists, the EBCM will provide a 5 volt output via the extended brake travel circuit to the ECM.
This diagnostic procedure supports the following DTC:
DTC P1575 Extended Travel Brake Switch Circuit
• | The ignition is ON. |
• | Ignition voltage is greater than 8 volts. |
One of the following conditions exist:
• | The extended brake travel voltage is less than 0.8 volts when extended brake travel is ON. |
• | The extended brake travel voltage is greater than 2.0 volts when extended brake travel is OFF. |
All systems remain functional.
• | 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. |
One of the following may cause this concern:
• | An open in the extended brake travel circuit. |
• | A short to ground or voltage in the extended brake travel circuit. |
The numbers below refer to the step numbers on the diagnostic table.
Measure the extended brake travel circuit in order to determine if the extended brake travel signal has a valid voltage.
Measure the extended brake travel signal in order to determine if the EBCM is functioning properly.
This vehicle is equipped with a ECM which uses an electrically erasable programmable read only memory (EEPROM). When replacing the ECM, the replacement ECM must be programmed.
Step | Action | Values | Yes | No | ||||||
---|---|---|---|---|---|---|---|---|---|---|
Schematic Reference: Antilock Brake System Schematics Connector End View Reference: Antilock Brake System Connector End Views , Engine Control Module Connector End Views in Engine Controls - 3.6L, or Engine Control Module Connector End Views in Engine Controls - 4.6L | ||||||||||
1 | Did you perform the Diagnostic System Check - Vehicle? | -- | Go to Step 2 | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information | ||||||
2 | Test the extended brake travel circuit of the electronic brake control module (EBCM) for the following conditions:
Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 9 | Go to Step 3 | ||||||
Is the voltage greater than the specified value? | 2 V | Go to Step 5 | Go to Step 4 | |||||||
Is the voltage of the extended brake travel signal greater than the specified value? | 0.8 V | Go to Step 6 | Go to Step 5 | |||||||
5 | Inspect for poor connections 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 9 | Go to Step 7 | ||||||
6 | Inspect for poor connections the harness connector of the engine control module (ECM). 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 | Replace the EBCM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming. Did you complete the replacement? | -- | Go to Step 9 | -- | ||||||
Replace the ECM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming. Did you complete the replacement? | -- | Go to Step 9 | -- | |||||||
9 |
Does the DTC reset? | -- | Go to Step 2 | System OK |