Land Rover Defender: Transfer Case - Diagnosis and Testing

DIAGNOSIS AND TESTING

PRINCIPLE OF OPERATION

For a detailed description of the transfer case system and operation, refer to the relevant Description and Operation section of the workshop manual.

INSPECTION AND VERIFICATION

CAUTION: Diagnosis by substitution from a donor vehicle is NOT acceptable. Substitution of control modules does not guarantee confirmation of a fault, and may also cause additional faults in the vehicle being tested and/or the donor vehicle.

NOTES:

• If a control module or a component is at fault and the vehicle remains under manufacturer warranty, refer to the Warranty Policy and Procedures manual, or determine if any prior approval program is in operation, prior to the installation of a new module/component.
• Generic scan tools may not read the codes listed, or may read only 5-digit codes. Match the 5 digits from the scan tool to the first 5 digits of the 7-digit code listed to identify the fault (the last 2 digits give extra information read by the Jaguar Land Rover approved diagnostic equipment).
• When performing voltage or resistance tests, always use a digital multimeter that has the resolution ability to view 3 decimal places. For example, on the 2 volts range can measure 1 mV or 2 kΩ range can measure 1 Ω. When testing resistance always take the resistance of the digital multimeter leads into account.
• Check and rectify basic faults before beginning diagnostic routines involving pinpoint tests.
• Inspect connectors for signs of water ingress, and pins for damage and/or corrosion.
• If DTCs are recorded and, after performing the pinpoint tests, a fault is not present, an intermittent concern may be the cause. Always check for loose connections and corroded terminals.
• Check the JLR claims submission system for open campaigns. Refer to the corresponding bulletins and SSMs which may be valid for the specific customer complaint and complete the recommendations as required.
• Guided Diagnostics may be accessed through the Jaguar Land Rover approved diagnostic equipment.
• Select Powertrain - Transmission and Driveline, then either - High or Low Range Selection, or - Reduced Traction

1. Verify the customer concern.
2. Visually inspect for obvious signs of damage and system integrity.

Visual Inspection

3. If an obvious cause for an observed or reported concern is found, correct the cause (if possible) before proceeding to the next step
4. If the cause is not visually evident, verify the symptom and refer to the Symptom Chart, alternatively check for Diagnostic Trouble Codes (DTCs) and refer to the DTC Index
5. Check JLR claims submission system for open campaigns. Refer to the corresponding bulletins and SSMs which may be valid for the specific customer complaint and complete the recommendations as required.

SYMPTOM CHART

DEFINITION OF JUDDER

When diagnosing faults involving vehicle judder, see guidance below for a working definition of the characteristics of the condition:

• Judder is an event which occurs while carrying out low speed tight turn maneuvres (car park type driving) and transmits through the vehicle chassis in the frequency range of 30Hz to 50Hz
• The judder frequency is dull and audible and is possible to sense through the steering wheel
• The judder event is a continuous dull vibration / judder which will occur for a number of seconds. It is not a single occurrence
• Judder will NOT occur while driving in a straight line
• Judder is associated with low speed tight turn driving at low to medium throttle (junction pull-aways and car park maneuvres) and may feel like there is something sticking in the system
• At full lock, some tire scrubbing may be experienced. As the temperature drops, such scrubbing may be experienced as stick/slip judder. This is normal and does not require any service intervention

TCCM DTC ERROR COUNT PINPOINT TESTS

In order to determine if certain Transfer Case Control Module (TCCM) DTCs have been set with sufficient frequency to require the replacement of the TCCM, follow the pinpoint test diagnostics outlined below:

PINPOINT TEST A : DTC SNAPSHOT - EXTENDED DATA CHECKS

TRANSFER CASE CONTROL MODULE DTC ACTION TABLE

TRANSFER CASE CLASSIFICATION AND CLASSIFICATION VERSION NUMBER LOCATION

Note the six digit code stamped on the transfer case (illustrated as YYYY.ZZ). The first four digits (YYYY) represent the classification number (in decimal), the final two digits (ZZ) represent the classification version (in decimal)

TRANSFER CASE SERVICE ROUTINES

There are a range of diagnostic and service procedures available for the transfer case and its constituent components (transfer case clutch, range selection mechanism, transfer case control module). A number of these procedures are exclusively used by the Pathfinder Tool Guided Diagnostic Flows, while others are available as standalone applications. Details of the transfer case/transfer case control module service routines and procedures are listed below:

STANDALONE APPLICATIONS (ECU SET-UP APPLICATIONS)

The following procedures may be accessed and run individually by the service technician and should be used to facilitate replacement of the transfer case, transfer case components or transfer case oil changes:

HIGH/LOW RANGE POSITION SENSOR REPLACEMENT APPLICATION (ROTARY POSITION SENSOR REPLACEMENT APP)

When a new high/low range position sensor is installed, this procedure must be performed using JLR approved diagnostic equipment to make sure the appropriate set-up and calibration procedures and to check the installation.

TRANSFER CASE REPLACEMENT APPLICATION

NOTE: The Transfer Case will be delivered with a transfer case control module already installed and calibrated.

Thus, there is no calibration work necessary

When a new transfer case is installed, this procedure must be performed using JLR approved diagnostic equipment to make sure the appropriate set-up and calibration procedures and to check the installation.

TRANSFER CASE OIL REPLACEMENT

Use this procedure whenever the transfer case oil requires replacement. This procedure must be performed using JLR approved diagnostic equipment.

TRANSFER CASE HEALTHCHECK APPLICATION

To perform a test of transfer case clutch and range change functionality, for example, to validate a transfer case repair, this procedure must be performed using JLR approved diagnostic equipment.

STANDALONE APPLICATIONS (MODULE SET UP REQUIREMENTS)

The following procedures may be accessed and run individually by the service technician and should be used to facilitate replacement or reprogramming of the transfer case control module:

TRANSFER CASE CONTROL MODULE REPLACEMENT APPLICATION

CAUTION: Warning: Driving the vehicle before the whole process is completed might cause damage in the transfer case

When a new transfer case control module is installed, this procedure must be performed using JLR approved diagnostic equipment to make sure the appropriate set-up and calibration procedures and to check the installation.

EXISTING MODULE PROGRAMMING APPLICATION

To reconfigure the transfer case control module with the latest level software, this procedure must be performed using JLR approved diagnostic equipment.

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