When a Land Rover shows a key-related warning, Pathfinder or SDD can read fault codes from the KVM that describe what the module has detected. Understanding what these codes mean helps avoid misdiagnosis and unnecessary parts replacement.
Common KVM Fault Code Categories
Key not programmed to this vehicle: the key presented to the KVM has no matching profile stored. This appears when a wrong key is used, when a previously deleted key is presented, or when a key from another JLR vehicle is accidentally tried. It is not a KVM hardware fault.
Key deactivated: the KVM has a profile for the key but has flagged it as disabled. Causes include repeated failed authentication attempts, software conflicts, or a specific deactivation command. Requires Pathfinder to reactivate or reprogram.
KVM communication fault: the diagnostic tool cannot establish communication with the KVM. Causes include low 12V battery, a faulty OBD port connection, a KVM that has lost power, or in rare cases a hardware fault in the module itself. Always check 12V and OBD connection before condemning the KVM.
Immobiliser active: the immobiliser is engaged and the engine will not start. This is a result code rather than a cause — it means a valid key was not authenticated on the last start attempt. Investigate which of the above causes is responsible.
What Fault Codes Cannot Tell You
KVM fault codes describe the state the module is in when the diagnostic tool reads it. They do not always pinpoint the root cause — a low 12V battery can generate fault codes that look like a KVM hardware failure. Always investigate the simpler causes first.
| Service | AJ Auto Price | Main Dealer Estimate |
|---|---|---|
| Land Rover spare key | From £180 | £400 to £900+ |
| Land Rover all keys lost | From £250 | £700 to £1,500+ |
For Land Rover key diagnosis and programming see the Land Rover key replacement page.
What We See in Practice
Fault code reading on Land Rover security systems is something we carry out as part of virtually every key-related callout. The information from the diagnostic report often changes the direction of a job entirely. We attend callouts where the owner has been told by a general mechanic that the KVM needs replacing, and the fault code read on site shows a voltage fault rather than a module fault, meaning a battery replacement resolves the issue without any module work. We also attend jobs where the owner assumes a key fault is battery-related, and the fault codes indicate a KVM offline error that persists regardless of battery voltage. Reading the codes before deciding on a course of action is never wasted time.
Frequently Asked Questions
What types of fault codes relate to Land Rover key systems?
Common categories include KVM communication faults, RFA module offline codes, immobiliser authentication errors, antenna circuit faults, and battery voltage-related security system warnings. Each code points to a different part of the system.
Can fault codes be read with a basic OBD reader?
Basic OBD readers access powertrain fault codes but typically cannot read body module or security system codes on Land Rover. JLR-specific diagnostic software is required to access the KVM, RFA and immobiliser data that key-related faults generate.
Do fault codes always identify the component that needs replacing?
Not always. A KVM communication fault might be caused by the KVM itself, the wiring, the 12V battery, or another module on the same communication bus. Fault codes narrow the diagnosis but a skilled technician uses them as a starting point rather than a definitive answer.
Can clearing fault codes fix a key problem?
Sometimes. If the fault code was triggered by a voltage event and the underlying cause has been resolved, clearing the code and retesting is a valid step. Codes that return immediately after clearing indicate a persistent fault that requires component-level attention.
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When to go to a dealer instead
If your vehicle is still under JLR factory warranty and the fault is covered, take it to a dealer. Warranty repairs are free and no specialist can match that. If you need a recall fix, the dealer is the right call. Outside of those two situations, a mobile JLR specialist will be faster, cheaper, and will attend at your location.