Split, perished, disconnected or pinched hose or tube in the leakage diagnostic pump circuit; Loose, damaged or incorrect fuel filler cap, or worn cap seal; Faulty leakage diagnostic pump, including a leaking internal diaphragm or reference orifice; Faulty or sticking purge valve or tank vent valve affecting the test; Wiring or connector fault at the pump or its valve, such as corrosion or a poor pin fit; Cracked charcoal canister or damaged filler neck.

P1476

Leakage Diagnostic Pump Clamped Tube.

BMW
Powertrain
Manufacturer code
Low severity

How this code is built

P: SystemPowertrain
1: Defined byThe manufacturer
4: AreaAuxiliary emission controls
76: FaultThe specific fault in that area

What it means

On BMW, P1476 relates to the leakage diagnostic pump (LDP) in the evaporative emission system, specifically a fault associated with the clamped tube. The engine control unit runs a self-test of the fuel tank ventilation system using the pump, and the expected pressure or pump response was not seen. The exact test method and the tube involved vary by model and engine, so confirm against model-specific data.

Symptoms

Engine management warning light on
Fuel smell around the rear of the car or near the engine bay
Fuel filler cap warning or message on some models
Difficulty refuelling, with the pump clicking off repeatedly
No noticeable driveability change in most cases
Failed emissions inspection due to the evaporative system fault

Possible causes

Split, perished, disconnected or pinched hose or tube in the leakage diagnostic pump circuitlikely
Loose, damaged or incorrect fuel filler cap, or worn cap seallikely
Faulty leakage diagnostic pump, including a leaking internal diaphragm or reference orificepossible
Faulty or sticking purge valve or tank vent valve affecting the testpossible
Wiring or connector fault at the pump or its valve, such as corrosion or a poor pin fitpossible
Cracked charcoal canister or damaged filler neckrare

How to diagnose

Read the stored codes and freeze frame data, then note any other evaporative or fuel system codes
Check the fuel filler cap is fitted correctly, undamaged and has an intact seal
Visually inspect all evaporative hoses, clamps and connections around the leakage diagnostic pump, canister and tank for splits, kinks or looseness
Inspect the pump and valve wiring and connectors for corrosion, damage or poor contact
Check the pump and valve electrical supply, earth and control signals against model-specific data
Use a scan tool with actuator tests, if supported for the model, to operate the pump and valve and listen for correct operation
Carry out a controlled smoke test of the evaporative system at low pressure to locate leaks
Clear the code after repair and run the system self-test to confirm it passes

How to fix

Replace or refit damaged, split or disconnected hoses and tubes, and secure the clamps correctly
Fit a correct, undamaged fuel filler cap
Replace the leakage diagnostic pump if testing shows it faulty
Replace a faulty purge valve or tank vent valve
Repair wiring or connector faults found in the pump circuit
Replace a cracked canister or damaged filler neck if found to be leaking

Can I keep driving?

Low severity

The car can normally be driven as the fault affects the evaporative system rather than engine running. Book it in soon, as fuel vapour may escape and the car may fail an emissions inspection.

Guide written by AI from the code's definition. Confirm with a diagnosis before replacing parts.