Land Rover Discovery: Automatic Transmission  Transaxle/ Diagnosis and Testing

PRINCIPLES OF OPERATION

For a detailed description of the Automatic Transmission, refer to the relevant Description and Operation section in the workshop manual. REFER to: Transmission Description (307-01 Automatic Transmission/Transaxle, Description and Operation).

INSPECTION AND VERIFICATION

CAUTIONS:

• 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.
• The vehicle should not be driven if the fluid level is low as internal failure can result.
• When the wheels are free of the ground (for example, when the vehicle is on a lift), do not drive the vehicle in any gear higher than 4th gear. Failure to comply with this instruction may cause DTCs to set or damage to the automatic transmission.

NOTES:

• If a control module or a component is suspect and the vehicle remains under manufacturer warranty, refer to the Warranty Policy and Procedures manual, or determine if any prior approval programme is in operation, prior to the installation of a new module/component.
• When performing voltage or resistance tests, always use a digital multimeter accurate to three decimal places, and with an up-todate calibration certificate. 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.
• A road test should be performed by a suitably qualified and experienced technician in accordance with: Jaguar Land Rover - Service Experience Framework (SEF) - 4.4 Road Test Check Sheet.

  The customer should be present and ideally should drive the vehicle.

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 DDW for open campaigns. Refer to the corresponding bulletins and SSMs which may be valid for the specific customer complaint and carry out the recommendations as required

SYMTOM CHART

SYMPTOM:

Warning message: TRANSMISSION FAULT

POSSIBLE CAUSES:

• Engine system fault
• Anti-lock brake system fault
• Active ondemand coupling system fault
• All wheel drive system fault
• Transmission system fault
• Powertrain control module software fault
• Transmission control module software fault

ACTION:

• Using the Jaguar Land Rover approved diagnostic equipment, check the powertrain control module for related DTCs and refer to the relevant DTC index
• Using the Jaguar Land Rover approved diagnostic equipment, check the anti-lock brake system control module for related DTCs and refer to the relevant DTC index
• Using the Jaguar Land Rover approved diagnostic equipment, check the active ondemand coupling control module for related DTCs and refer to the relevant DTC index
• Using the Jaguar Land Rover approved diagnostic equipment, check the all wheel drive control module for related DTCs and refer to the relevant DTC index
• Using the Jaguar Land Rover approved diagnostic equipment, check the transmission control module for related DTCs and refer to the relevant DTC index
• Using the Jaguar Land Rover approved diagnostic equipment, re-configure the powertrain control module with the latest level software
• Using the Jaguar Land Rover approved diagnostic equipment, re-configure the transmission control module with the latest level software

SYMPTOM:

Gearshift quality poor

POSSIBLE CAUSES:

• Engine and transmission installation
• Engine system fault
• Anti-lock brake system fault
• Climate control system fault
• Active ondemand coupling system fault
• All wheel drive system fault
• Gateway system fault
• Transmission system fault
• Powertrain control module software not at the latest level
• Anti-lock brake system control module software not at the latest level
• Automatic temperature control module software not at the latest level
• Active ondemand coupling control module software not at the latest level
• All wheel drive control module software not at the latest level
• Gateway module software not at the latest level
• Transmission control module software not at the latest level
• Transmission adaptions insufficient for smooth gearshifts

ACTION:

• GO to Pinpoint Test A.

SYMPTOM:

Automatic transmission fluid leak

POSSIBLE CAUSES:

• Selector shaft seal leaking
• Torque converter seal leaking
• Automatic transmission fluid pan seal leaking
• Halfshaft seal leaking
• Transmission cover gasket leaking
• Oil supply pipe seal leaking
• Distribution cover plate gasket leaking
• Automatic transmission fluid level plug leaking
• Automatic transmission fluid cooler hose seal leaking
• Automatic transmission fluid cooler hose leaking
• Automatic transmission fluid cooler leaking

ACTION:

• Install a new selector shaft seal
• Install a new torque converter seal
• Install a new automatic transmission fluid pan seal
• Install a new halfshaft seal
• Install a new transmission cover gasket
• Install a new oil supply pipe seal
• Install a new distribution cover plate gasket
• Install a new automatic transmission fluid level plug
• Install a new automatic transmission fluid cooler hose seal
• Install a new automatic transmission fluid cooler hose
• Install a new automatic transmission fluid cooler

• Fluid Level and Condition Checks
• Automatic Transmission  Transaxle / Routines

Engine Speed and Torque MonitoringFluid Level and Condition Checks

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