For 1990-2009 cars
ABS Components
Antilock Brake System Schematics
Power Distribution Schematics
Power Distribution Schematics
Power Distribution Schematics
Power Distribution Schematics
Handling Electrostatic Discharge Sensitive Parts Notice

### Circuit Description

This DTC identifies a malfunction within the EBCM. When the EBCM relay is activated (turned on), voltage is supplied to the valve solenoids and pump motor.

### Conditions for Running the DTC

The ABS/TCS conditions are normal.

### Conditions for Setting the DTC

DTC C1256 is set when an internal EBCM malfunction exists.

### Action Taken When the DTC Sets

• | ABS/TCS is not disabled.

• | ABS/TCS Indicators are not turned on.

### Conditions for Clearing the DTC

• | Condition for DTC is no longer present and scan tool clear DTC function is used.

• | 100 ignition cycles have passed with no DTCs detected.

### Diagnostic Aids

Possible cause for DTC C1256 to set is an internal relay problem within the EBCM.

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
1 | Did you perform the ABS Diagnostic System Check? | -- | Go to Step 2 | Go to Diagnostic System Check - ABS
2 |

1. Install a scan tool.
2. Turn ON the ignition, with the engine OFF.
3. With a scan tool, observe the DTC Information parameter in the ABS/TCS Diagnostic Trouble Codes (DTCs).

Does the scan tool display other ABS/TCS DTCs?

--

Go to Diagnostic Trouble Code (DTC) List/Type

Go to Step 3

3 | Inspect for poor connections/terminal tension at the EBCM harness connector. 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 5 | Go to Step 4
4 | Replace the EBCM. Refer to Electronic Brake Control Module Replacement Did you complete the repair? | -- | Go to Step 5 | --
5 |

1. Use the scan tool in order to clear the DTCs.
2. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.

Does the DTC reset?

--

Go to Step 2

System OK