Circuit Description
The normally closed outlet valves operate similarly to the inlet valves. When the EBCM/EBTCM grounds an outlet valve, however, the valve opens instead of closes.
The EBCM/EBTCM opens an outlet valve for short periods in order to reduce pressure at the left rear wheel.
Conditions for Setting the DTC
The DTC C1256 sets when the EBCM/EBTCM detects an open or short to ground in the left rear outlet valve circuit.
Action Taken When the DTC Sets
The following actions are taken when the DTC sets:
| • | A malfunction DTC is stored |
| • | The ABS is disabled |
| • | The ANTILOCK indicator lamp is turned ON |
Conditions for Clearing the DTC
The DTC will clear under following conditions:
| • | Conditions for the malfunction are no longer present. Use the scan tool clear DTCs function. |
| • | 100 ignition switch key cycles have passed without detecting any malfunctions |
Diagnostic Aids
Perform a thorough inspection of the wiring and the connectors.
Failure to inspect wiring carefully may result in a misdiagnosis. A misdiagnosis may result in replacing parts without repairing the malfunction.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 | Was the ABS Diagnostic System Check performed? | -- | Go to Step 2 | |
2 |
Is the resistance less than the specified value? | 2 ohms | Go to Step 3 | Go to Step 13 |
3 | Use the J 39200 in order to measure the resistance between the BPMV connector C1 terminal 14 and the BPMV assembly block. Is the resistance within the specified range? | OL (Infinite) | Go to Step 4 | Go to Step 13 |
4 | Use the J 39200 in order to measure the resistance between the BPMV connector C1 terminal 14 and terminal 10. Is the resistance within the specified range? | 3-6 ohms | Go to Step 5 | Go to Step 13 |
5 |
Is the resistance less than the specified value? | 2 ohms | Go to Step 6 | Go to Step 9 |
6 |
Is the resistance less than the specified value? | 2 ohms | Go to Step 7 | Go to Step 10 |
7 |
Is the resistance within the specified range? | OL (Infinite) | Go to Step 8 | Go to Step 11 |
8 |
Is the voltage greater than the specified value? | 1 V | Go to Step 12 | Go to Step 14 |
9 | Repair the open or high resistance in CKT 1291. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | -- | |
10 | Repair the open or high resistance in CKT 1451. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | -- | |
11 | Repair the short to ground in CKT 1291. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | -- | |
12 | Repair the short to voltage in CKT 1291. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | -- | |
13 | Replace the BPMV. Refer to Brake Pressure Modulator Valve Replacement . Is the repair complete? | -- | -- | |
14 | Replace the EBCM/EBTCM. Refer to Electronic Brake and Traction Control Module Replacement . Is the repair complete? | -- | -- |
