The 4WD low signal circuit is used to notify the powertrain control module (PCM) that the vehicle is in 4WD low range. The PCM supplies 12 volts to this circuit. The transfer case shift control module grounds this circuit when the vehicle is in 4WD low range.
This DTC detects a short to ground, short to voltage, or an open in the 4WD low signal circuit.
This diagnostic procedure supports the following DTC:
DTC C0359 Four Wheel Drive Low Range (4WD low) Discrete Output Circuit Malfunction
• | The ignition is ON. |
• | The system voltage is 9-18 volts. |
• | After the transfer case shift control module grounds the output, the 4WD low signal circuit, and reads back a high voltage, the DTC is set. The system will not attempt setting the DTC 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. |
• | Transmission shift points may be affected. |
• | The SERVICE 4WD indicator will be latched on for the remainder of the current ignition cycle. |
• | 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 33 consecutive ignition cycles without a fault present. |
• | History DTCs can be cleared using a scan tool. |
The numbers below refer to the step numbers on the diagnostic table.
Tests for proper reference voltage to the transfer case shift control module on the 4WD low signal circuit.
Tests the 4WD low signal circuit for a short to voltage.
Tests the 4WD low signal circuit for an open or high resistance.
Repairs the 4WD low signal circuit for a short to voltage.
Step | Action | Values | 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 |
Is the voltage reading within the specified values? | 10-13.5 V | Go to Step 3 | Go to Step 4 | |
Is the voltage reading within the specified value? | 0 V | Go to Step 7 | Go to Step 5 | |
Test the 4WD low signal circuit for an open, a high resistance, or a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 8 | Go to Step 6 | |
Repair the 4WD low signal circuit for short to voltage. Refer to Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 8 | -- | |
6 | Replace the PCM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming. Did you complete the repair? | -- | 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. Did you complete the repair? | -- | Go to Step 8 | -- |
8 |
Does the DTC reset? | -- | Go to Step 2 | System OK |