Symptom Chart

SYMPTOM	POSSIBLE CAUSES	ACTION
Front wheels spinning (also include increased SCS intervention for example Flashing lights)	Rear differential internal failure PTU internal failure Driveshaft or halfshaft damage Invalid data received on communication bus	Using the Jaguar Land Rover approved diagnostic equipment, check for AWD system related DTC s and perform the relevant repair procedures Using the Jaguar Land Rover approved diagnostic equipment, run application - All-Wheel-Drive Functional Test Using the Jaguar Land Rover approved diagnostic equipment, run application - Control Clutch Torque (SD)/Control Clutch Torque (AD)
Instrument cluster message "2 Wheel Drive Only - Traction Reduced"	Rear differential internal failure PTU internal failure Driveshaft or halfshaft damage One or more driveline control modules are off bus Invalid data received from the Anti-lock Brake System (ABS) control module or Powertrain Control Module (PCM)	Using the Jaguar Land Rover approved diagnostic equipment, check for AWD system related DTC s and perform the relevant repair procedures Using the Jaguar Land Rover approved diagnostic equipment, run application - All-Wheel-Drive Healthcheck
Loss of traction (for example: Understeer during corner acceleration, unable to get up a low mud incline where the vehicle should normally have no issues)	Rear differential internal failure PTU internal failure Driveshaft or halfshaft damage Invalid data received on communication bus	Using the Jaguar Land Rover approved diagnostic equipment, check for AWD system related DTC s and perform the relevant repair procedures Using the Jaguar Land Rover approved diagnostic equipment, run application - Control Clutch Torque (SD)/Control Clutch Torque (AD) Using the Jaguar Land Rover approved diagnostic equipment, run application - All-Wheel-Drive Calibrate Clutches
Poor fuel economy	Driveline remaining connected	Using the Jaguar Land Rover approved diagnostic equipment, check for AWD system related DTC s and perform the relevant repair procedures Using the Jaguar Land Rover approved diagnostic equipment, run application - All-Wheel-Drive Functional Test
Vehicle pulling to one side	Different rolling circumference of the rear road wheels (Active Driveline only) Road surface Chassis damage or incorrect alignment	Using the Jaguar Land Rover approved diagnostic equipment, check for AWD system related DTC s and perform the relevant repair procedures
Whining gear noise	Water in oil Rear Drive Unit (RDU) Rear Drive Unit (RDU) bearing wear/failure PTU bearing wear/failure Dirt ingress to the drive unit	Check for excessive radial or axial play in the pinion for the Rear Drive Unit (RDU) and PTU Check for excessive radial play in the rear halfshafts Seal failure (oil leaks) can be a sign of ingress to drive unit which can then lead to gear noise Seal failure (oil leaks) can be a sign of halfshaft or pinion excessive runout due to bearing wear/failure causing gear misalignment and gear whine
Sudden bang noise at any vehicle speed	PTU failure to connect Debris from the road hitting the bottom of the vehicle Damaged/broken driveshaft or halfshaft	Using the Jaguar Land Rover approved diagnostic equipment, run application - Power Transfer Unit - Connect Test - to check functionality of the PTU Inspect the underside of the vehicle for damage caused by debris impact Inspect driveshaft and halfshafts for damage
Constant clicking during low to moderate speed cornering	Damaged/worn Constant Velocity joint (CV) joint	Check CV boot for damage and tears Check for evidence of loss of CV joint grease Check for excessive play in the CV joint Replace halfshaft
Clicking at low speed, up to 10 kph	Heatshield (petrol only) PTU connect	Check the heatshield is installed correctly Using the Jaguar Land Rover approved diagnostic equipment, run application - Power Transfer Unit - Connect Test - to check functionality of the PTU
Rumbling noise from the rear of the vehicle varying at different vehicle speed and load	Rear differential internal failure Road noise Worn or damaged driveshaft joint/halfshafts Wheel bearings Another component contacting the front/rear drive halfshaft/driveshaft	Using the Jaguar Land Rover Approved Diagnostic Equipment perform routine - Noise, vibration and harshness - Diagnostic test - Rear differential. This will assist with diagnosis of the faulty components Check for DTC s Using the Jaguar Land Rover approved diagnostic equipment, run application - Control Clutch Torque (SD)/Control Clutch Torque (AD) Check for excessive play in halfshafts, wheel bearings and driveshaft
Noise is at constant tone over a narrow vehicle speed range. Usually heard on light drive and coast conditions	Rear drive axle	Using the Jaguar Land Rover Approved Diagnostic Equipment perform routine - Noise, vibration and harshness - Diagnostic test - Rear differential. This will assist with diagnosis of the faulty components
Whine/humming/squealing noise is the same on drive or coast	Road noise Worn or damaged driveshaft joint Driveshaft center bearing Wheel bearing Rear Differential internal failure	Road test the vehicle on varying road surfaces to confirm the issue is mechanical and not road surface noise Using the Jaguar Land Rover approved diagnostic equipment perform routine - Noise, vibration and harshness - Diagnostic test - Rear differential. This will assist with diagnosis of the faulty components Rear Drive Unit/Power Transfer Unit (RDU/PTU ) oil change - inspect oil for debris or excessive metal flakes
Noise is produced when the vehicle is stationary and when driving	Engine Transmission	For transmission diagnostics. REFER to: DIAGNOSTICS
Humming/whining noise when the vehicle is stationary	Rear Drive Unit/Power Transfer Unit (RDU/PTU ) actuator noise	Using the Jaguar Land Rover approved diagnostic equipment, run application - Power Transfer Unit - Connect Test Using the Jaguar Land Rover approved diagnostic equipment, run application - Control Clutch Torque (SD)/Control Clutch Torque (AD) and check for excessive noise
Loud clunk in the driveline when shifting from reverse to forward	Transmission calibration Transmission Mount Transmission Suspension components Backlash in the driveline Engine mount	Using the Jaguar Land Rover approved diagnostic equipment, re-configure the Transmission Control Module (TCM) with the latest available calibration Inspect and install new transmission mounts as required For transmission diagnostics. REFER to: DIAGNOSTICS Inspect and install new suspension components as required Inspect and install new driveline components as required Inspect and install new engine mounts as required
Clicking, popping, or grinding noises	Inadequate or contaminated lubrication in the front/rear drive halfshaft CV joint Another component contacting the front/rear drive halfshaft Wheel bearings, brakes or suspension components Front halfshaft link-shaft bearing failure/wear Front halfshaft link-shaft bearing cap/strap failure	Inspect, clean and lubricate with new grease as required Make sure all other components are clear from front/rear drive halfshaft Inspect and install new components as required Check for radial play of the link-shaft bearing within the bearing cap/strap Check bearing cap is secured correctly
Vibration at highway speeds	Out of balance wheel(s) or tire(s) Driveshaft misaligned/out of balance Driveshaft center bearing touching body mounting point Driveshaft bearing wear/failure	Using the Jaguar Land Rover approved diagnostic equipment perform routine - Noise, vibration and harshness - Diagnostic test - Wheel imbalance candidate. Balance wheels as required Check the driveshaft alignment and re-align as required Note the mounting position of the driveshaft in relation to the drive pinion flange and drive pinion flange damper. Disconnect the driveshaft, rotate the driveshaft 180 degrees and reinstall. Road test the vehicle to verify the symptom has cleared Check for excessive radial play in the driveshaft
Shudder, Vibration During Acceleration	Powertrain/driveline misalignment High CV joint operating angles caused by incorrect ride height Driveshaft centre bearing wear/failure	Check for powertrain/driveline misalignment and rectify as required. Install new components as required Check the ride height and verify the correct spring rate. Install new components as required Check for excessive radial play in the driveshaft
Judder knocking from rear at low speed when cornering	Rear Drive Unit (RDU) over-delivering torque to rear axle Contamination of the Rear Drive Unit (RDU) clutches Difference of rolling road circumference	Check if there is any water in the Rear Drive Unit (RDU) oil Using the Jaguar Land Rover approved diagnostic equipment, run application - Control Clutch Torque (SD)/Control Clutch Torque (AD) Rear Drive Unit (RDU) oil change. If clutches are contaminated, the noise should disappear after performing a 2 mile (3.2 kilometer) road test, following a Rear Drive Unit (RDU) oil change
RDU Lubricant Leak	Rear drive axle breather Damaged seal Rear drive axle filler plug Rear drive axle drain plug	Check the oil level and correct as required Install a new driveshaft/pinion seal as required Check and install a new filler plug as required Check and install a new drain plug as required Re-seal leaking joints as required Inspect rear drive axle housing for impact damage or cracks
PTU Lubricant Leak	PTU breather Damaged seal PTU filler plug PTU drain plug	Check the oil level and correct as required Install a new driveshaft/pinion seal as required Check and install a new filler plug as required Check and install a new drain plug as required Re-seal leaking joints as required Inspect PTU housing for impact damage or cracks
NOTE: 20MY L550, L551 only Burnt oil smell from the PTU and possible visible oil leak from the PTU pinion oil seal	PTU over heat condition due to the following: Incorrect wheel size installed to the vehicle Incorrect tire pressures Contaminated PTU oil PTU internal failure	GO to PINPOINT TEST A .