GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2005 🢒 Blazer - 4WD 🢒 Restraints 🢒 SIR 🢒 DTC C0362

Circuit Description

The 4WD low circuit is used to inform the powertrain control module (PCM) when the transfer case has been placed into 4WD low mode. The PCM supplies the circuit with a 12-volt signal. When the transfer case is placed into 4WD low, the transfer case shift control module pulls the 12-volt signal low which is then sensed by the PCM.

This DTC detects an internal module fault or a short to voltage on the 4WD low signal circuit.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC C0362 4WD Low Discrete Output Circuit High

Conditions for Running the DTC
    • The ignition is ON.
    • The system voltage is 9-16 volts.

Conditions for Setting the DTC
    • After the system turns the output on, grounding the 4WD Low Signal Circuit, and reads back a high voltage, the DTC is set. The system will not attempt it again during that ignition cycle.
    • The transfer case shift control module reads back a high voltage when a low voltage is expected on the 4WD low Signal Circuit.

Action Taken When the DTC Sets
    • May affect the transmission shift points.
    • The SERVICE 4WD indicator will be ON for the remainder of the current ignition cycle.

Conditions for Clearing the DTC
    • The transfer case shift control module will clear the DTC if the condition for setting the DTC no longer exits.
    • A history DTC will clear after 100 consecutive ignition cycles without a fault present.
    • History DTCs can be cleared using a scan tool.

Test Description

The numbers below refer to the step numbers on the diagnostic table.

  1. Tests the 4WD low circuit for voltage.

    2.

  2. Tests the 4WD low circuit for a short to voltage.

    3.

  3. Tests the 4WD low circuit for an open or high resistance.

    4.

  4. Repairs the 4WD low circuit for a short to voltage.

DTC C0362

Step

Action

Yes

No

Schematic Reference: Transfer Case Control Schematics

Connector End View Reference: Transfer Case Control Connector End Views

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle in Vehicle DTC Information

2

  1. Turn the ignition OFF.
  2. Disconnect the transfer case shift control module.
  3. Connect a DMM between the 4WD low circuit and ground.
  4. Turn the ignition ON with the engine OFF.

Does the DMM indicate battery voltage?

Go to Step 3

Go to Step 4

3

  1. Turn the ignition OFF.
  2. Disconnect the PCM.
  3. Turn the ignition ON with the engine OFF.

Does the DMM continue to show battery voltage?

Go to Step 5

Go to Step 7

4

Test the 4WD low circuit for an open or high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Was the condition found and corrected?

Go to Step 8

Go to Step 6

5

Repair the 4WD low circuit for a short to voltage. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

Go to Step 8

--

6

Replace the PCM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.

Is the replacement complete?

Go to Step 8

--

7

Replace the transfer case shift control module. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.

Is the replacement complete?

Go to Step 8

--

8
  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