C0256
Circuit Description
The EBCM internal relay supplies battery voltage to all six valve solenoids.
The EBCM applies the grounds needed to activate each solenoid. The low side of each solenoid coil has a feedback circuit to the EBCM microprocessor. When a solenoid is commanded off, feedback voltage is high. When a solenoid is commanded on, feedback voltage is low.
Conditions for Running the DTC
^ The ignition is ON.
^ The IPC bulb check is complete.
^ The vehicle is moving at a speed greater than 5 km/h (3 mph).
Conditions for Setting the DTC
Open Solenoid/Shorted Control Circuit DTC(s).
The EBCM microprocessor detects low feedback voltage from a solenoid that is commanded off.
Shorted Solenoid/Open Control Circuit DTC(s)
The EBCM microprocessor detects high feedback voltage from a solenoid that is commanded on.
Action Taken When the DTC Sets
^ The ABS indicator is commanded on.
^ The ABS is disabled for the remainder of the ignition cycle.
^ The BRAKE indicator is commanded on (C0243, C0244, C0247 and C0248 only).
Conditions for Clearing the DTC
^ Repair the condition(s) responsible for setting the Diagnostic Trouble Code (DTC).
^ Use a scan tool in order to clear the DTC.
Diagnostic Aids
An intermittent open/shorted solenoid DTC can be set by a number of internal EBCM problems. Replace the EBCM if an open/shorted solenoid DTC continues to set intermittently.