BMW P0513: Incorrect Immobilizer Key — Diagnosis and Repair

P0513 means Incorrect Immobilizer Key. The DME records it when the presented key identity or start authorization does not match the immobilizer data accepted by the vehicle; diagnosis must prove the named circuit or mechanism before parts are replaced. Use OBDThink to preserve the recording module and freeze frame for P0513, then test key transponder authorization, CAS or BDC, DME start enable and related communication in the condition that set the fault. What Does P0513 Mean? This standardized powertrain DTC concerns key transponder authorization, CAS or BDC, DME start enable and related communication. BMW component location and test routing vary by engine, chassis and DME software; use the VIN-specific wiring diagram and service plan. The code is not a parts verdict. Its defining evidence is that the presented key identity or start authorization does not match the immobilizer data accepted by the vehicle, so compare command, actual response and electrical integrity in the same operating window. Code: P0513 Definition: Incorrect Immobilizer Key Module: DME (gasoline) or DDE where applicable Key evidence: the presented key identity or start authorization does not match the immobilizer data accepted by the vehicle Typical causes: a damaged or unprogrammed key, weak key battery where relevant, interference, CAS or BDC power loss, antenna fault, module synchronization issue, or unauthorized module replacement Severity: diagnose promptly Note: confirm engine and circuit variant by VIN First save the freeze frame. If the presented key identity or start authorization does not match the immobilizer data accepted by the vehicle, test key transponder authorization, CAS or BDC, DME start enable and related communication before disconnecting parts or erasing the evidence. Symptoms • The characteristic pattern is a no-crank or crank-no-start event, key-not-recognized message and missing DME start authorization despite normal battery voltage. • The freeze frame is most useful when it captures that the presented key identity or start authorization does not match the immobilizer data accepted by the vehicle. • A graph of the affected channel beside its companion or target value exposes dropouts that a static scan misses. • Related faults should be sorted by time and module so a shared supply or mechanical cause is not mistaken for a second failure. Possible Causes Begin with accessible connections and supporting conditions, prove the component dynamically, and reserve expensive internal work for last. • Low cost: inspect terminal grip, contamination, strain and loom routing at key transponder authorization, CAS or BDC, DME start enable and related communication. • Low cost: verify the exact fuse, shared feed, ground, hose or oil path shown for the VIN instead of assuming a universal BMW layout. • Medium cost: dynamically test the named sensor, valve or actuator; decisive evidence is that the presented key identity or start authorization does not match the immobilizer data accepted by the vehicle. • Medium cost: correct the verified system fault, with branches including a damaged or unprogrammed key, weak key battery where relevant, interference, CAS or BDC power loss, antenna fault, module synchronization issue, or unauthorized module replacement. • High cost: consider DME repair or internal mechanical work only after circuit loading, signal comparison and the VIN-specific BMW test plan agree. Diagnosis Steps with OBDThink OBDThink is an independent BMW coding and diagnostic mobile app and is not affiliated with BMW AG. Live data and freeze frame depth depend on the vehicle, adapter and module. • 1. Scan all modules with OBDThink; save P0513, the recording DME, status, frequency, companion faults and freeze frame before clearing. • 2. Recreate the stored condition safely and graph the affected signal against its target or redundant channel. Scan CAS or BDC and DME together, record key status and start enable, try an authorized spare key, and inspect module power and the key antenna before synchronization or replacement. • 3. Inspect key transponder authorization, CAS or BDC, DME start enable and related communication; with power isolated where required, load-test supply and ground and check the signal dynamically rather than trusting continuity alone. • 4. Separate electrical from mechanical evidence by moving the harness while logging, then perform the relevant smoke, waveform, pressure, airflow, compression or oil-path test. • 5. After the proven repair, clear faults, repeat the relevant cold start or controlled drive cycle, and rescan every related module. IF the presented key identity or start authorization does not match the immobilizer data accepted by the vehicle AND the circuit load test fails -> repair the circuit ELSE IF the command is valid but the mechanism does not respond -> test key transponder authorization, CAS or BDC, DME start enable and related communication ELSE compare companion faults and the BMW VIN-specific test plan THEN clear, reproduce the condition, and rescan The fastest split is command versus response while testing key transponder authorization, CAS or BDC, DME start enable and related communication: a lost electrical load and a mechanically unresponsive part require different repairs. Repair • Low cost: reseat or repair the proven connector, terminal, wire, hose, ground, fuse path or oil-service error affecting key transponder authorization, CAS or BDC, DME start enable and related communication. • Medium cost: replace the confirmed sensor, valve, solenoid, coil, injector or actuator; perform only the adaptation specified for that VIN. • Medium cost: repair the demonstrated intake, EVAP, fuel, exhaust, airflow or oil-supply condition instead of masking its measurement. • High cost: repair the DME, timing hardware, cylinder head, pump or internal engine only when BMW service-data tests exclude cheaper branches. After repair, verify that the presented key identity or start authorization does not match the immobilizer data accepted by the vehicle no longer occurs and that P0513 stays absent as pending and confirmed through the relevant monitor. Can You Drive with P0513? The fault usually prevents starting rather than creating a driving hazard; do not bypass immobilizer security or repeatedly drain the battery. Treat P0513 as measured evidence. The saved operating condition, target-to-actual comparison and loaded circuit test identify the least costly defensible repair.