Circuit Description
The electronic brake control module (EBCM) is wired to the ignition 1 voltage circuit to indicate the ignition ON/OFF state. The EBCM monitors this voltage and the voltage on the front wheel speed sensor voltage supply circuits to ensure that the voltages remain within an acceptable operating range. The EBCM cannot operate properly when the system voltage is too low.
DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC C0899 Device Voltage Low
Conditions for Running the DTC
| • | The ignition is ON. |
| • | The power mode is not detected as being CRANK. |
Conditions for Setting the DTC
Either of the following conditions may cause the DTC to set.
| • | The EBCM detects voltage below 9.5 volts at the ignition 1 circuit for 2 seconds. |
| • | The EBCM detects voltage below 7.3 volts at either of the front wheel speed sensor voltage supply circuits for 20 seconds. |
Action Taken When the DTC Sets
The following actions may occur when this DTC sets.
| • | The EBCM disables the ABS/TCS. |
| • | The EBCM disables the dynamic rear proportion (DRP). |
| • | The Antilock Brake System (ABS) indicator turns ON. |
| • | The brake warning indicator turns ON. |
| • | The ABS fault message is displayed. |
| • | The traction fault message is displayed. |
| • | The brakes message is displayed. |
Conditions for Clearing the DTC
The Conditions for Setting the DTC are no longer present and you use the scan tool Clear DTCs function.
Diagnostic Aids
Although 2-20 seconds of low voltage detection are required to set this DTC, ABS related systems may be disabled by the EBCM during the fault detection process, and prior to setting this DTC. This means that the instrument panel cluster (IPC) may turn ON indicators, and fault messages, intermittently, without the EBCM setting any DTCs if low voltage faults are intermittent.
Step | Action | Values | Yes | No |
|---|---|---|---|---|
Schematic Reference: Antilock Brake System Schematics Connector End-View Reference: Antilock Brake System Connector End Views | ||||
1 | Did you perform the Diagnostic System Check - Vehicle? | -- | Go to Step 2 | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information |
2 | Is DTC C0035 set as either a Current or History DTC? | -- | Go to DTC C0035 | Go to Step 3 |
3 |
Does the DTC set? | -- | Go to Step 4 | Go to Diagnostic Aids |
4 | Perform the Diagnostic System Check - Vehicle in Vehicle DTC Information. Did you find and correct the condition? | -- | Go to Step 9 | Go to Step 5 |
5 |
Does the resistance measure within the specified range? | 0-0.2 ohms | Go to Step 7 | Go to Step 6 |
6 | Repair the high resistance in the ignition 3 voltage circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you complete the repair? | -- | Go to Step 9 | -- |
7 | 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 9 | Go to Step 8 |
8 | 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 | -- |
9 |
Does the DTC reset? | -- | Go to Step 3 | System OK |
