Scan before codes are cleared
Connect a tool capable of communicating with the exact model generation and record a complete report before deleting anything. Save fault code, module, status, mileage or time counter and freeze-frame data where available. A seller who clears faults immediately removes useful evidence and may reset readiness information needed to judge whether repairs were completed.
Generic OBD is only the first layer
A basic reader normally concentrates on emissions-related engine data. It may not reach the automatic gearbox, transfer case, active differential, air suspension, electronic parking brake, ABS, steering, battery management, restraint, body control, climate, cameras or infotainment modules. “No engine light” and “no generic codes” therefore leave most of the vehicle untested.
Use a recognised Land Rover-capable system or a specialist inspection. Coverage varies by tool, subscription and vehicle year, so confirm the modules actually responding rather than assuming a brand logo means complete access.
Check module communication
A module that does not communicate can indicate a tool limitation, blown fuse, low voltage, network fault, water damage, missing equipment or an incorrectly configured replacement. Compare the reported module list with the vehicle’s actual specification. Numerous communication codes may share one power, earth or network cause.
Separate current, historic and secondary faults
A historic code may relate to an old repair or temporary low voltage. A current or repeatedly returning code deserves more weight. Neither should be interpreted in isolation. One failing wheel-speed sensor can trigger ABS, suspension, Terrain Response and gearbox messages; one weak battery can populate many modules with voltage or communication errors.
Record battery voltage before starting, during cranking and with the engine running. If voltage is poor, preserve the first scan, correct the supply issue and then reassess what returns. Do not use “battery fault” as a blanket explanation for an engine, gearbox or structural symptom.
Use live data to test a claim
Live data can compare commanded and actual air-suspension heights, wheel speeds, gearbox temperature, boost pressure, DPF pressure, coolant temperature and charging behaviour. The useful values depend on the exact vehicle. A number outside a generic internet range is not automatically a failed part; compare sensors, operating conditions and manufacturer information.
For diesel vehicles, assess DPF and emissions data alongside journey pattern and oil history. A forced regeneration is not a repair for an underlying temperature, pressure, EGR, injector or driving-cycle problem. For PHEVs and newer networked vehicles, high-voltage diagnosis should be performed only with suitable training and equipment.
Look for signs of a recent reset
Incomplete emissions readiness, no history on a vehicle displaying symptoms, reset adaptation values or a suspiciously short time since codes were cleared can indicate recent intervention. There can be innocent reasons—a battery replacement or completed repair—but ask for evidence and rescan after the test drive.
A fault code is not a parts order
Codes identify a circuit, condition or system response; they rarely prove which component must be replaced. Check wiring, connectors, power, earth, mechanical causes and related modules. Parts swapping can make a complicated Land Rover more expensive without solving the initiating fault.
If the scan shows serious powertrain, braking, restraint, steering, high-voltage or network faults, obtain a written specialist assessment before purchase. The cost of diagnosis is small compared with buying a vehicle whose warnings were temporarily erased.
What to keep from the viewing
Save the pre-drive report, note which codes were current, complete the road test, then scan again without clearing. Photograph dashboard messages and record conditions when they appeared. Attach this evidence to the service-history timeline and physical inspection. Together they create a much stronger basis for negotiation than a green tick from a code reader.