The EBCM interfaces with a scan tool through terminal 4 via to Data Link Connector (DLC) terminal 7. A properly set scan tool connected to the DLC can retrieve ABS diagnostic information like Diagnostic Trouble Codes (DTCs) and perform ABS device control for testing purposes.
Inspect for the following list of items when diagnosing this part of the Antilock Brake System (ABS):
• | An open ECU-IG fuse |
• | An open ABS fuse |
• | A clean tight G103 |
The EBCM will not interface with a scan tool if these circuits have excessive resistance:
• | The serial data line |
• | The ignition power circuit |
• | G103 |
Ensure that these circuits are in good condition and that no excessive resistance occurs. Also inspect the EBCM electrical connector for poor connector terminal contact.
The numbers below refer to the step numbers on the diagnostic table.
This test determines if the scan tool can communicate with any other modules on the Class 2 serial data line.
Tests for a short to ground in the ignition positive voltage circuit.
Tests the EBCM ground circuit for an open or high resistance.
Tests the ignition positive voltage circuit for an open or high resistance.
Step | Action | Value(s) | Yes | No |
---|---|---|---|---|
1 | Did you perform A Diagnostic System Check - ABS? | -- | Go to Step 2 | |
Does the scan tool communicate with any other modules on the serial data line? | -- | Go to Step 3 | Go to Scan Tool Does Not Communicate with Components in Data Link Communications | |
3 |
Is the fuse open? | -- | Go to Step 4 | Go to Step 5 |
Did you find and correct the condition? | -- | Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems | ||
5 | Inspect the EBCM ground circuit, making sure that the ground is clean and torqued to the proper specification. Refer to Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 6 | |
Did you find and correct the condition? | -- | Go to Step 7 | ||
Test the Ignition Positive Voltage circuit for an open or high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 8 | ||
8 | 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 | |
9 | Replace the Brake Modulator Assembly. Refer to Brake Pressure Modulator Valve Assembly Replacement . Did you complete the replacement? | -- | -- |