CEL codes P2407 and P0455

[famfeld]

After fueling up one snowy night in March, the CEL lit up and has been since. I got codes 2407 and 0455 which indicate the leak detection pump circuit intermittent/erratic and major leak respectively. My gas cap seal is all cracked up. Any ideas?
Thanks for the continued help.
Feld

Gas cap seal

[abscate]

I think I’ve got a spare Gates one if you want Tom give that a try first, FELD.

Since those two things are linked in function, I would replace gap, then clear codes, then drive it to see what comes back

I don’t think the 2000 uses a leak pump, is this on a newer P2 car?

[famfeld]

I am driving a 2004 xc70 now. Forgot to mention.

[RickHaleParker]

Clear the codes and see what comes back. Fix the fault in the Leak diagnostic unit, ECM-431D (P2407, before you go chasing the ECM-404C (P0455), which maybe a incorrect detection due to a faulty leak detector.

ECM-431D (P2407) Leak diagnostic unit. Faulty signal

Diagnostic trouble code (DTC) information

M2302861 Condition
Diagnostic trouble code (DTC) ECM-431D (signal too high or too low) is stored if the power consumption of the pump in the leak diagnostic unit is higher or lower than a particular value during the reference phase.
Diagnostic trouble code (DTC) ECM-431D (faulty signal) is stored if the power consumption for the pump in the leak diagnostic unit fluctuates too much during the reference phase.
The power consumption of the pump must drop when the leak diagnostic pump valve moves from the reference check to pressurizing the fuel tank system. Diagnostic trouble code (DTC) ECM-431D (signal missing) is stored if the value for the power consumption of the pump drops too quickly, slowly or not at all.
The diagnosis is carried out when the ignition is switched off.
For more information about the leak diagnostics, see Leak diagnostics (certain markets only) .

Substitute value
The leak diagnostic is disabled.

Possible source
Signal too high:

• Contact resistance in the terminals
  Blocked filter in the leak diagnostic unit
  Blocked hose between the filter and the leak diagnostic unit
  Defective leak diagnostic unit.

Signal too low:

• Contact resistance in the terminals
  Defective leak diagnostic unit.

Faulty signal:

• Contact resistance in the terminals
  Defective leak diagnostic unit
  Defective control of the heater element (This fault is detected by the central electronic module).

Signal missing:

• Contact resistance in the terminals
  Blocked hose between the leak diagnostic pump and the EVAP canister
  Defective leak diagnostic unit.

Fault symptoms
Malfunction indicator lamp (MIL) lit.

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ECM-404C (P0455) Fuel tank system, leakage. Major leak
Print

Diagnostic trouble code (DTC) information

M2302861 Condition
If no fault is detected in the leak diagnostic unit, the control module runs a leak diagnostic of the fuel tank system. Diagnostic trouble code (DTC) ECM-400C is stored if the engine control module (ECM) detects a leak of 0.5-1.0 mm (minor leak) or a leak that is >1.0 mm (major leak). For more information about the leak diagnostics, see Leak diagnostics (certain markets only) .

Substitute value
None.

Possible source
Major leak:

• Fuel tank filler cap missing or not tightened
  Leakage that is 1 mm or greater in the fuel tank, fuel filler pipe, fuel tank filler cap, EVAP canister, canister purge (CP) valve, or in the hoses between these components
  The fuel gauge does not function (This fault is detected by the rear electrical module).

Minor leak:

• Leakage that is 0.5-1.0 mm or smaller in the fuel tank, fuel filler pipe, fuel tank filler cap, EVAP canister, canister purge (CP) valve, or in the hoses between these components
  The fuel gauge does not function (This fault is detected by the rear electrical module).

Fault symptoms
Malfunction indicator lamp (MIL) lit.