The EBCM microprocessor grounds the isolation coil to energize and close the isolation valve. This will prevent any additional brake pressure applied by the driver from reaching the wheel. Further increases in brake pressure will be prohibited. Each isolation valve is closed independently to isolate each wheel.
Isolation time (pressure hold) exceeds 120 seconds.
• | The ABS indicator lamp turns on |
• | The ABS disables |
DTCs C0269 and C0274 are ignition latched DTCs, which indicates that the above actions remain true until the ignition switch is turned to OFF (even if the cause of the DTC is intermittent).
• | Repair the conditions responsible for setting the DTC |
• | Use the Scan Tool Clear DTCs function |
Repair any other DTCs first. Then perform the Function Test of the scan tool in order to ensure proper operation of the ABS.
If DTCs C0269 or C0274 are setting after replacing the EBCM, check the vehicle for an auxiliary device (winch, auxiliary battery system, etc.) which could cause a voltage spike on the battery feed to the EBCM. If the vehicle does have an auxiliary device, install a Metallic Oxide Varistor (MOV) in the battery feed circuit to the EBCM.
The numbers below refer to the steps in the diagnostic table:
This step determines the resistance of the power ground circuit.
This step determines the battery voltage available to the EBCM.
This step determines the resistance of the signal ground circuit.
This step determines the ignition voltage available to the EBCM.
Step | Action | Value(s) | Yes | No |
---|---|---|---|---|
1 | Was the Diagnostic System Check performed? | -- | Go to Step 2 | |
2 |
Is the connector in good condition? | -- | Go to Step 3 | Go to Step 11 |
Using a J 39200 , measure the resistance between terminal B of the 2-way EBCM harness connector and the ground . Is the resistance measurement within the specified range? | 0-2 ohms | Go to Step 4 | Go to Step 12 | |
Using a J 39200 , measure the voltage between terminal A of the 2-way EBCM harness connector and the ground . Is the voltage equal to or greater than the specified value? | 10.0 V | Go to Step 6 | Go to Step 5 | |
5 | Inspect the grey fusible link. Is the grey fusible link open? | -- | Go to Step 13 | Go to Step 14 |
6 |
Is the connector in good condition? | -- | Go to Step 7 | Go to Step 15 |
Measure the resistance between terminal J of the 10-way EBCM harness connector and the ground using a J 39200 . Is the resistance measurement within the specified range? | 0-2 ohms | Go to Step 8 | Go to Step 16 | |
Is the voltage equal to or greater than the specified value? | 10.0 V | Go to Step 10 | Go to Step 9 | |
9 | Inspect the 15-amp I-3 fuse. Is the fuse open? | -- | Go to Step 17 | Go to Step 18 |
10 | Malfunction is intermittent, perform the following:
Does the DTC set as a current DTC? | -- | Go to Step 19 | Go to Diagnostic Aids |
11 | Repair the 2-way EBCM harness connector. Refer to Connector Repairs . Is the repair complete? | -- | -- | |
12 | Repair the open or the high resistance in the CKT 350. Refer to Wiring Repairs . Is the repair complete? | -- | -- | |
13 | Repair the short to ground in the CKT 442. Refer to Wiring Repairs . Is the repair complete? | -- | -- | |
14 | Repair the open or the high resistance in the CKT 442. Refer to Wiring Repairs . Is the repair complete? | -- | -- | |
15 | Repair the 10-way EBCM harness connector. Refer to Connector Repairs . Is the repair complete? | -- | -- | |
16 | Repair the open or the high resistance in the CKT 451. Refer to Wiring Repairs . Is the repair complete? | -- | -- | |
17 | Repair the short to ground in the CKT 241. Refer to Wiring Repairs . Is the repair complete? | -- | -- | |
18 | Repair the open or the high resistance in the CKT 241. Refer to Wiring Repairs . Is the repair complete? | -- | -- | |
19 | Replace the EBCM. Refer to Electronic Brake Control Module Replacement . Is the repair complete? | -- | -- |
The EBCM microprocessor grounds the isolation coil to energize and close the isolation valve. This will prevent any additional brake pressure applied by the driver from reaching the wheel. Further increases in brake pressure will be prohibited. Each isolation valve is closed independently to isolate each wheel.
Isolation time (pressure hold) exceeds 120 seconds.
• | The ABS indicator lamp turns on |
• | The ABS disables |
DTCs C0269 and C0274 are ignition latched DTCs, which indicates that the above actions remain true until the ignition switch is turned to OFF (even if the cause of the DTC is intermittent).
• | Repair the conditions responsible for setting the DTC |
• | Use the Scan Tool Clear DTCs function |
Repair any other DTCs first. Then perform the Function Test of the scan tool in order to ensure proper operation of the ABS.
If DTCs C0269 or C0274 are setting after replacing the EBCM, check the vehicle for an auxiliary device (winch, auxiliary battery system, etc.) which could cause a voltage spike on the battery feed to the EBCM. If the vehicle does have an auxiliary device, install a Metallic Oxide Varistor (MOV) in the battery feed circuit to the EBCM.
The numbers below refer to the steps in the diagnostic table:
This step determines the resistance of the power ground circuit.
This step determines the battery voltage available to the EBCM.
This step determines the resistance of the signal ground circuit.
This step determines the ignition voltage available to the EBCM.
Step | Action | Value(s) | Yes | No |
---|---|---|---|---|
1 | Was the Diagnostic System Check performed? | -- | Go to Step 2 | |
2 |
Is the connector in good condition? | -- | Go to Step 3 | Go to Step 11 |
Using a J 39200 , measure the resistance between terminal B of the 2-way EBCM harness connector and the ground . Is the resistance measurement within the specified range? | 0-2 ohms | Go to Step 4 | Go to Step 12 | |
Using a J 39200 , measure the voltage between terminal A of the 2-way EBCM harness connector and the ground . Is the voltage equal to or greater than the specified value? | 10.0 V | Go to Step 6 | Go to Step 5 | |
5 | Inspect the grey fusible link. Is the grey fusible link open? | -- | Go to Step 13 | Go to Step 14 |
6 |
Is the connector in good condition? | -- | Go to Step 7 | Go to Step 15 |
Measure the resistance between terminal J of the 10-way EBCM harness connector and the ground using a J 39200 . Is the resistance measurement within the specified range? | 0-2 ohms | Go to Step 8 | Go to Step 16 | |
Is the voltage equal to or greater than the specified value? | 10.0 V | Go to Step 10 | Go to Step 9 | |
9 | Inspect the 15-amp I-3 fuse. Is the fuse open? | -- | Go to Step 17 | Go to Step 18 |
10 | Malfunction is intermittent, perform the following:
Does the DTC set as a current DTC? | -- | Go to Step 19 | Go to Diagnostic Aids |
11 | Repair the 2-way EBCM harness connector. Refer to Connector Repairs . Is the repair complete? | -- | -- | |
12 | Repair the open or the high resistance in the CKT 350. Refer to Wiring Repairs . Is the repair complete? | -- | -- | |
13 | Repair the short to ground in the CKT 442. Refer to Wiring Repairs . Is the repair complete? | -- | -- | |
14 | Repair the open or the high resistance in the CKT 442. Refer to Wiring Repairs . Is the repair complete? | -- | -- | |
15 | Repair the 10-way EBCM harness connector. Refer to Connector Repairs . Is the repair complete? | -- | -- | |
16 | Repair the open or the high resistance in the CKT 451. Refer to Wiring Repairs . Is the repair complete? | -- | -- | |
17 | Repair the short to ground in the CKT 241. Refer to Wiring Repairs . Is the repair complete? | -- | -- | |
18 | Repair the open or the high resistance in the CKT 241. Refer to Wiring Repairs . Is the repair complete? | -- | -- | |
19 | Replace the EBCM. Refer to Electronic Brake Control Module Replacement . Is the repair complete? | -- | -- |