DTC C0306. Chevrolet Kodiak C-Series (Conventional) C4/C5 2009

For 1990-2009 cars only

Makes 🢒 Chevrolet 🢒 2009 🢒 Kodiak C-Series (Conventional) C4/C5 🢒 Safety and Security 🢒 Supplemental Inflatable Restraints 🢒 DTC C0306

Diagnostic Instructions

•	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 C0306: Motor A or B Circuit Malfunction

The transfer case motor is a bi-directional, permanent magnet, DC motor. When energized, through motor control A or motor control B, the ground is provided by the opposing motor control circuit and then grounded through the transfer case shift control module ground circuit, the motor, through a series of gears, rotates a shaft which moves the mode and range forks to shift the transfer case between the following ranges:

•

2HI

•

4HI

•

4LO

•

Neutral

This DTC detects an open, short to voltage, or short to ground in the motor control A or motor control B circuits, or an open, or short to ground inside the motor.

Conditions for Running the DTC

•	The ignition is ON.

•	The system voltage is 9-18 volts.

Conditions for Setting the DTC

•	The system tests the motor circuits by checking for unwanted voltage.

•	Then, the system supplies voltage on each of the motor circuits and reads the voltage back on the other circuit.

•	If the system detects a condition with the circuits, the DTC is logged. The transfer case shift control module senses a low voltage return in the motor control A or motor control B circuits when a high voltage is expected.

•	The fault must remain current for 30 seconds to set the DTC.

Action Taken When the DTC Sets

•	All shifting is disabled.

•	The SERVICE 4WD indicator is not illuminated.

•	The transfer case shift control module provides a reference voltage of 4.5 volts on the motor A/B line for diagnostic purposes.

Conditions for Clearing the DTC

•	The transfer case shift control module will clear the DTC if the condition for setting the DTC is not currently present.

•	A history DTC will clear after 100 consecutive ignition cycles without a fault present.

•	History DTCs can be cleared using a scan tool.

Reference Information

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.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.