What are the most common Jaguar XJ problems?
According to Au7o's analysis of 5,200+ owner reports, the 2012 Jaguar XJ has 12 documented issues. The most frequently reported are: Air Suspension Compressor Failure, X351 Water Pump and Plastic Coolant Pipe Failure Under the Supercharger, AJ133 5.0 V8 Timing Chain Tensioner Ratchet and Plastic Guide Rail Wear. Of these, 4 are rated critical and should be addressed promptly.
Is the Jaguar XJ reliable?
The 2012 Jaguar XJ has 12 known issues documented across 5,200+ owner reports. 4 issues are rated critical: Air Suspension Compressor Failure and X351 Water Pump and Plastic Coolant Pipe Failure Under the Supercharger and AJ133 5.0 V8 Timing Chain Tensioner Ratchet and Plastic Guide Rail Wear and 306DT 3.0 V6 Diesel Crankshaft and Main Bearing Failure. Prospective buyers should inspect for these issues and factor potential repair costs into their purchase decision. Regular maintenance following the manufacturer's schedule helps prevent many common problems.
How much does it cost to fix common Jaguar XJ problems?
Repair costs for known Jaguar XJ issues range from $0 to $15,000, depending on the specific problem and whether you choose DIY or professional repair. The most critical issue, Air Suspension Compressor Failure, typically costs $1,000-$3,000 to repair. Au7o provides step-by-step DIY maintenance guides that can help reduce repair costs.
What is the 2004-2019 Jaguar XJ Air Suspension Compressor Failure?
The Dunlop or Hitachi air suspension compressor on the XJ fails due to overwork from leaking air springs or aging valve blocks. The compressor runs continuously, overheats, and eventually burns out. This is one of the most common and expensive repairs on the XJ. Repairs typically run $1,000-$3,000. Severity: high.
What is the 2010-2019 Jaguar XJ X351 Water Pump and Plastic Coolant Pipe Failure Under the Supercharger?
The X351's cooling system fails in a pattern quite unlike the X350's. On the 5.0 V8 and the 3.0 supercharged V6, the water pump seal and bearing can fail remarkably early — owners have reported failures under 20,000 miles — and the small-diameter plastic connectors that plug into… Repairs typically run $900-$2,500. Severity: high.
What is the 2010-2015 Jaguar XJ AJ133 5.0 V8 Timing Chain Tensioner Ratchet and Plastic Guide Rail Wear?
The 5.0-litre AJ133 V8 fitted to the X351 has a widely documented timing drive weakness that has nothing to do with the earlier 4.2 AJ34's plastic tensioner story — the X350's 4.2 already ran metal tensioners and Morse chains, and merging the two engines' histories is the standar… Repairs typically run $3,500-$9,000. Severity: high.
What is the 2011-2019 Jaguar XJ 306DT 3.0 V6 Diesel Crankshaft and Main Bearing Failure?
The 3.0-litre V6 diesel (306DT / AJ-V6D) sold in the X351 in markets outside North America has a documented bottom-end weakness that is specific to that engine and does not apply to the petrol V6 or either V8. The crankshaft is compact and narrow, leaving thin sections between th… Repairs typically run $6,000-$15,000. Severity: high.
What is the 2004-2012 Jaguar XJ Electrical Gremlins from Body Control Module Issues?
The XJ suffers from cascading electrical faults caused by body control module (BCM) software glitches and CAN bus communication errors. Phantom warning lights, inoperative features, and intermittent failures across multiple systems are common, especially after battery disconnecti… Repairs typically run $200-$1,500. Severity: medium.
What is the 2004-2019 Jaguar XJ Rear Main Seal Oil Leak on V8 Engines?
The rear crankshaft main seal on AJ-V8 engines in the XJ develops a slow oil leak over time. The leak worsens as the seal hardens and the crankshaft seal surface develops minor wear grooves. Oil drips onto the transmission bellhousing and can contaminate the clutch on manual mode… Repairs typically run $800-$2,000. Severity: medium.
What is the 2010-2019 Jaguar XJ Supercharger Nose Cone Bearing Wear?
The Eaton TVS supercharger on the XJR and Supersport develops bearing wear in the nose cone assembly. The bearings dry out over time, producing a whining noise that increases with RPM. The coupler between the supercharger and the drive pulley also wears, causing rattle at idle. Repairs typically run $1,200-$3,500. Severity: medium.
What is the 2010-2016 Jaguar XJ Supercharger Torsional Isolator Coupler Backlash ('Marbles in a Can' Rattle) — TSB JTB00349?
A separate component and a separate failure from supercharger nose cone bearing wear: the AJ133 supercharger drive uses a spring-loaded torsional isolator on the blower's nose pulley to damp driveline shock. The end of the original spring bears directly against plastic, and over… Repairs typically run $900-$2,800. Severity: medium.
What is the 2010-2019 Jaguar XJ JaguarDrive Rotary Gear Selector Fails to Rise on Start-Up?
The X351 uses the JaguarDrive rotary selector that rises out of the centre console when the engine starts and retracts when it shuts down. The mechanism that lifts the dial fails, leaving the selector stuck flush in the console. Because gear selection is by-wire through that dial… Repairs typically run $400-$1,500. Severity: medium.
What is the 2010-2019 Jaguar XJ Panoramic Roof and Powered Sunblind Motor Failure / Loss of Calibration?
The X351's panoramic roof is a more complex assembly than the X350's simple sunroof: the front glass panel tilts and slides on its own motor, and there are two additional motorised fabric sunblinds, front and rear, each with its own drive. Owners report the roof or the blinds ref… Repairs typically run $200-$1,800. Severity: medium.
What is the 2010-2019 Jaguar XJ AJ133 5.0 V8 / AJ126 3.0 SC V6 Engine-Driven Brake Vacuum Pump Seal Oil Leak (X351)?
The 2010-2019 X351's petrol engines drive a mechanical brake-booster vacuum pump off the camshaft at the front of the engine. The pump's plastic housing and its seal to the cylinder head harden and leak, leaving oil across the front of the engine and on the undertray; it is frequ… Repairs typically run $300-$1,200. Severity: low.
What is the 2010-2019 Jaguar XJ X351 LED Tail Lamp Condensation and Water Pooling from Failed Housing Seam and Vent Bungs?
Condensation inside the wrap-around LED tail lamps is close to universal on the 2010-2019 X351. The lamps use LEDs that never get hot enough to dry the housing, and the two plastic vent bungs on the back of each unit trap moisture; when the sonic-welded seam between the lens and… Repairs typically run $0-$1,200. Severity: low.
