GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2009 🢒 Canyon Pickup - 4WD 🢒 Engine 🢒 Engine Electrical 🢒 DTC C0901

Diagnostic Information
    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    •  Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC C0901: Device 2 Voltage Low - EBCM

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

Ignition 1 Signal

C0901

C0901

--

--

Ground

--

C0901

--

--

Circuit/System Description

The electronic brake control module (EBCM) monitors the ignition 1 voltage (IGN1) level available for system operation. A low voltage condition prevents the system from operating properly.

Conditions for Running the DTC

The ignition is ON.

Conditions for Setting the DTC
    •  Ignition 1 (IGN1) voltage to the EBCM is less than 6.5 volts for 7 seconds.
    • Vehicle speed is greater than 3 km/h (2 mph).

Action Taken When the DTC Sets

The brake warning indicator turns ON.

Conditions for Clearing the DTC
    • The DTC passes when the condition for the DTC is no longer present.
    • The EBCM automatically clears a history DTC when a current DTC is not detected in 100 consecutive drive cycles.

Reference Information

Schematic Reference

Antilock Brake System Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

ABS Description and Operation

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification
  1. Engine running, accessories OFF, measure and record the voltage at the battery voltage at the battery terminals. The voltage should be between 12.6 and 15.0 volts.
    2. ⇒If not within the specified range, refer to Charging System Test .
  2. Observe the scan tool EBCM Battery Voltage parameter. The reading should be between 12.60 and 15.00 volts.

Circuit/System Testing
  1. Ignition OFF, disconnect the harness connector at the EBCM.
  2. Ignition OFF and scan tool disconnected, open and close the driver door, and wait 1 minute. Test for less than 5 ohms between the ground circuit terminals listed below and ground:
    3. • Terminal 2
    • Terminal 3
    ⇒If greater than the specified range, test the ground circuit for an open/high resistance.
  3. Verify that a test lamp illuminates between the B+ circuit terminals listed below and ground:
    4. • Terminal 1
    • Terminal 4
    ⇒If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.
  4. Ignition ON, verify that a test lamp illuminates between the ignition circuit terminal 21 and ground.
    5. ⇒If the test lamp does not illuminate, test the ignition circuit for a short to ground or an open/high resistance.
  5. If all circuits test normal, replace the EBCM.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for EBCM replacement, setup, and programming.