Regeneration system leaking (causal chain) ME-SFI - fault code description - AD07.61-P-4000-17M

1	Fault code	P2013 Major leak in purge system (P0455)
	(Fault code according to OBD)	P2014 Minor leak in purge system, a minor leak (P0422) P2015 Purge control system has leak (function chain) (P0440) P2075 Minor leakage in purge system, micro leakage (P0446)
2	Fault storage	After expiry of test duration and fault
	Actuation CHECK ENGINE indicator lamp (MIL)	Following two successive driving cycles with faults
3	Checking frequency	Once per driving cycle
4	Checked signal or status	Change in speed of pressure values at the tank pressure sensor
5	Fault setting conditions
	Major leakage in purge system	Vacuum build-up of approx. 0.8 mbar per second is not achieved
	Minor leakage in purge system, Minor leakage ≥ 1 mm	For a closed system the vacuum should not decrease more rapidly than 0.3 to 0.7 mbar per second (dependent on fuel level).
	Minor leakage in purge system, micro leakage, ≥ 0.5 mm	For a closed system the vacuum should not decrease more rapidly than 0.1 to 0.15 mbar per second (dependent on fuel level).
	Checking duration	A maximum of 30 s for testing for major and minor leakages At least 50 seconds for checking for a micro leak
6	Check prerequisites	Vehicle stationary Engine idling Air pressure more than approx. 750 hPa (i.e. no test is performed above a height of approx. 2500 meters) Coolant temperature less than 101°C Charge air temperature of -1°C to +80°C Drive position "D" or "R" is engaged Low loading of activated charcoal canister Locking time after cold start elapsed (approx. 17 minutes) or mixture adaptation takes place Fuel in the fuel tank sloshing about excessively (inadmissible pressure surges) is recognized by the fuel tank pressure sensor (B4/3) and the test is terminated Lambda control and mixture adaptation enabled Air injection not active Fuel level in fuel tank of 30 to 90% No fault in activated charcoal canister shut-off valve No fault in fuel tank pressure sensor No fault in purge switchover valve function (opening/closing) Battery voltage higher than 11 volts.
7		The test for minor and micro leaks is aborted if an excessive lean correction of the lambda closed-loop control takes place during the vacuum buildup. Operation of the purge control valve (Y58/1) is checked at the same time as it is actuated. If the closed valve jams or it is blocked, a gross leak fault is stored. In the case of a gross leak the display in the instrument cluster shows "Tank cap missing" and the fuel reserve display flashes. If the activated charcoal canister shut-off valve jams open the fault major leak or fuel tank cap missing is stored. In the event of faults, check all hose lines (it hisses clearly with a leak in excess of 3 mm in size) The tests are not inhibited if there is an implausible fill level resulting from a faulty fuel gage sensor.

Any checks for leaks must be capable of detecting leaks from as small as 0.5 mm in the purge system. To do this a pressure test is carried out with the engine idling and with the vehicle stationary

Testing takes place in three stages:

Test for major leaks
Test for a minor leak (equal to or greater than 1 mm)
Test for a micro leak (equal to or greater than 0.5 mm)

Test for major leaks

The activated charcoal canister shut-off valve (Y58/4) is closed and the purge control valve (Y58/1) opened. The intake manifold vacuum flows to the fuel tank and a vacuum builds up in the fuel tank. This is detected by the fuel tank pressure sensor (B4/3).

If there is no vacuum build-up in the fuel tank (approx. -6 mbar within approx. 15 seconds), there is a major leak (e.g. fuel tank cap open, loose hose line). The diagnosis is terminated and the fault major leak in purge system is stored.

If the ME-SFI [ME] control unit recognizes a major leak in the system, the fuel reserve warning lamp in the instrument cluster flashes and "CHECK FILLER CAP" appears in the multifunction display.

Test for a minor leak

The purge control valve (Y58/1) is closed once a certain vacuum exists (approx. -6 mbar). The system is now likewise closed. The vacuum is them measured for approx. 30 seconds. It must not drop any faster than 0.3 to 0.5 mbar per second (depending on the level of fuel in the tank). If the vacuum drops more rapidly, there is a minor leak.

Check for micro leakage

If no minor leak has been detected, the purge system is briefly enabled and a vacuum of approx. -6 mbar is built up again. The vacuum must not drop any faster than 0.1 to 0.15 mbar per second for a closed system (depending on the level of fuel in the tank).

The reduction in the vacuum depends on the fill level in the fuel tank and on the degassing of the fuel. Degassing of the fuel is measured for a short time prior to the test and is allowed for in the fault statement. No test is conducted during the driving cycle if the fuel tank is filled to less than 30 %.

The activated charcoal canister shut-off valve (Y58/4) is reopened after the tests have been conducted.