MP 3023/3024-NQH - Transfer Case

DTC C0896

Diagnostic Instructions

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

DTC Descriptors
DTC C0896 03
- Device Voltage Range Below Threshold

DTC C0896 07
- Device Voltage Range Above Threshold

Circuit/System Description

The transfer case shift control module (TCCM) monitors the battery voltage feed to the TCCM. This DTC detects if the battery voltage is out of range. This could indicate a vehicle wide issue in which all electrical components would be affected, or it could be TCCM specific due to poor power or ground connections.

Conditions for Running the DTC

* Ignition ON.
* System voltage 10.5-18.5 V.

Conditions for Setting the DTC

System voltage above 18.5 V or below 10.5 and a mode shift is requested.

Action Taken When the DTC Sets

* Shifting disabled until battery voltage is within specification.
* Mode indicator will illuminate current mode.

Conditions for Clearing the DTC

* The TCCM clears the DTC once the conditions for setting the DTC are no longer present.
* A history DTC clears after 40 consecutive warm up cycles without a fault present.
* History DTCs can be cleared using a scan tool.

Diagnostic Aids

* Any mode shift requested when the battery voltage is below 12 V may set this DTC.
* Improperly connecting the cables during a jump start can cause C0896 07 to set.
* The Transfer Case High/Low Clutch Reset Transfer Case High/Low Clutch Reset procedure may need to be performed after repair.
* EL-49742 - harness is a good source for B+ and ground.

Reference Information
Schematic Reference

Transfer Case Control Schematics MP 3023/3024-NQH - Transfer Case
Connector End View Reference

Component Connector End Views Connector End Views By Name
Electrical Information Reference

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

Scan Tool Reference

Control Module References Programming and Relearningfor scan tool information.
Special Tools

EL-49742 - Battery Voltage B+ and Ground Source Harness

Circuit/System Verification

1. Verify that the TREC fuse, and the Miscellaneous IGN fuse, underhood fuse block, are not open.

• If the TREC fuse is open, test the battery positive voltage circuit, TCCM harness X3 pin C, for a short to ground.
• If the Miscellaneous IGN fuse is open, test the Ignition 1 voltage circuit, TCCM harness X2 pin 6, for a short to ground.

2. Ignition ON, engine OFF.
3. Using the Freeze Frame feature of the scan tool, review the Battery Voltage parameter when the DTC sets. The voltage should be above 12.0 V.

• If the voltage is above 18.5 V, this is likely a vehicle issue such as an alternator problem, or the vehicle has been hooked up improperly during a jump start. Refer to Symptoms - Engine Electrical Symptoms - Engine Electrical.

4. Using the Transfer Case Data Display feature of the scan tool, monitor the Battery Voltage parameter. The voltage should be above 12.0 V.

• If the voltage is below 12.0 V, ensure that the battery is fully charged and working properly. Refer to Battery Inspection/Test Battery Inspection/Test , Battery Common Causes of Malfunction Battery Common Causes of Malfunction and Battery Electrical Drain/Parasitic Load Test Battery Electrical Drain/Parasitic Load Test.

5. While monitoring the Battery Voltage parameter, start the engine. Rev the engine to greater than 3000 RPM. The voltage should remain stable and below 18.5 V.

• If the voltage is unstable or is greater than 18.5 V, ensure that the charging system is working properly. Refer to Charging System Test Charging System Test.

Circuit/System Testing

Note: When test probing harness terminals, it is imperative to use the proper test probe from the most current version of the J 35616 - Kit. Use of an improper test probe may deform the terminal, resulting in intermittent open conditions.

1. Key OFF. Disconnect the X3 harness connector at the TCCM.
2. Measure the voltage at the battery. The voltage should be above 12.0 V.

• If the voltage is below 12.0 V, ensure that the battery is fully charged and working properly. Refer to Battery Inspection/Test Battery Inspection/Test , Battery Common Causes of Malfunction Battery Common Causes of Malfunction and Battery Electrical Drain/Parasitic Load Test Battery Electrical Drain/Parasitic Load Test.

3. Install EL-49742 - harness. Test for B+ (+0.0/-0.5 V) between the 12 volt terminal (red) and the ground terminal (black) of EL-49742 - harness.

• If the voltage is less than the specified value, a vehicle wide issue is indicated. Inspect the battery positive circuit wire routing for chafed wires or damaged inline harness connectors that could cause unexpected voltage drops.

4. Using the purple probe J 35616-4A, test for B+ (+0.0/-0.5 V) between the battery positive voltage circuit, TCCM X3 pin C, and the ground terminal of EL-49742 - harness , black terminal.

• If the voltage is less than the specified range, test the battery positive voltage circuit for an open/high resistance or short to ground.

5. Using the purple probes J 35616-4A, test for B+ (+0.0/-0.5 V) between the battery positive voltage circuit, TCCM X3 pin C, and the ground circuit TCCM X3 pin D.

• If the voltage is less than the specified range, test the ground circuit for an open/high resistance, short to ground or short together condition.

Repair Instructions

Perform the Diagnostic Repair Verification Verification Tests after completing the diagnostic procedure.

* Transfer Case High/Low Clutch Reset Transfer Case High/Low Clutch Reset
* Battery Inspection/Test Battery Inspection/Test
* Battery Common Causes of Malfunction Battery Common Causes of Malfunction
* Battery Electrical Drain/Parasitic Load Test Battery Electrical Drain/Parasitic Load Test
* Charging System Test Charging System Test