* Transfer Case Shift Control Switch Replacement (Without SLT) (See: Powertrain Management/Transmission Control Systems/Sensors and
Switches - Transmission and Drivetrain/Sensors and Switches - Transfer Case/Four Wheel Drive Selector Switch/Service and Repair)
* Control Module References (See: Testing and Inspection/Programming and Relearning) for TCSCM replacement, setup, and programming
* Transfer Case High/Low Clutch Reset (See: Transmission and Drivetrain/Transfer Case/Testing and Inspection/Symptom Related Diagnostic
Procedures/MP 3023/3024-NQH - Transfer Case/Transfer Case High/Low Clutch Reset)
B0790
DTC B0790
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System
Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Strategy Based Diagnosis) for an
overview of the diagnostic approach.
* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure
Instructions) provides an overview of each diagnostic category.
DTC Descriptors
DTC B0790 01
- Neutral Indicator Circuit Short to Battery
DTC B0790 06
- Neutral Indicator Circuit Short to Ground or Open
Diagnostic Fault Information
Circuit/System Description
The Neutral indicator circuit consists of a light emitting diode (LED) feed circuit, a LED and a LED control circuit. The Ignition 1 voltage circuit is
the LED feed circuit and continuously supplies B+ to the Neutral LED. When the Neutral mode has been selected by the driver, the transfer case
shift control module (TCCM) provides a ground through the Neutral indicator control circuit illuminating the LED.
The TCCM tests the Neutral indicator circuit for unexpected voltage by monitoring the B+ supplied by the BCM on the Ignition 1 voltage circuit by
grounding the Neutral indicator control circuit for 2 seconds during the Bulb Test at key ON.
Conditions for Running the DTC
B0790 01
* Ignition ON
* System voltage 10-18 V
* Instrument panel lights not dimmed.
* Daylight running lights MUST be commanded ON.
* Circuit tested when the Neutral indicator is commanded ON.
B0790 06
* Ignition ON
* System voltage 10-18 V
* Instrument panel lights not dimmed.
* Daylight running lights MUST be commanded ON.
* Circuit tested when the Neutral indicator is commanded OFF.
Conditions for Setting the DTC
B0790 01
The TCCM detects 3.4 V or greater on the AWD/4WD Auto indicator control circuit when the Neutral indicator is commanded ON.
B0790 06
The TCCM detects 1.6 V or less for 1.5 seconds on the AWD/4WD Auto indicator control circuit when the Neutral indicator is commanded OFF.
