Land Rover Defender: Speed Control - Diagnosis and Testing

DIAGNOSIS AND TESTING

PRINCIPLES OF OPERATION

For a detailed description of the Speed Control system, refer to the relevant Description and Operation section in 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 not to specification 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 Diagnostic Trouble Code(s) (DTC)s 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.

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 the Cruise Control Module (CCM) for Diagnostic Trouble Codes ( DTCs) and refer to the DTC Index REFER to: Diagnostic Trouble Code Index - DTC: Cruise Control Module (CCM)
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

CRUISE CONTROL MODULE (CCM) ADJUSTMENT (VEHICLES WITH ADAPTIVE SYSTEM INSTALLED)

NOTES:

• If there are no DTCs set in the CCM, contact Jaguar Land Rover technical assistance before replacing the CCM
• If any DTCs are set that indicate a fault with the speed sensor/radar or with the adaptive cruise control system both the adaptive cruise control module sensor and the front radiator grille should be inspected for damage. If damage is evident to either the sensor or the front radiator grille, the damaged component should be replaced
• If a new cruise control module (CCM) is installed, make sure that the sensor is aligned after installation as described in the adaptive cruise control module sensor adjustment procedure. Make sure that all diagnostic trouble codes ( DTCs) have been cleared/resolved following the road test

An incorrectly aligned cruise control module can cause incorrect system operation. Before starting any repair work on the speed control system, on vehicles with the adaptive system installed, check adaptive cruise control module sensor for correct vertical and horizontal alignment, and complete the cruise control module adjustment procedure using the "Activate Forward Radar Service Alignment" application which can be accessed through Pathfinder (ECU Diagnostics > Cruise Control Module (CCM) > ECU Functions.

For a detailed description of the cruise control module (CCM) adjustment procedure, refer to the relevant sections in the workshop manual.

SYMPTOM CHART

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