Evaporative Leak OBD Fault Rectification Guide

Determine Which DTC Has Been Stored

Using the manufacturer approved diagnostic system, choose diagnostic session  , then choose the following symptom paths : Powertrain/engine system/fuel vapor and odor, Powertrain/engine system/fuel tank, Electrical/instruments/warning lamps/engine malfunction lamp/lamp illuminated, Powertrain/engine system/engine performance/fuel consumption high 

DTC	Description
P0442-00	DMTL small leak
P0447-00	DMTL COV electrical low (open)
P0448-00	DMTL COV electrical high
P0455-00	DMTL rough leak
P2401-00	DMTL pump electrical low (open)
P2402-00	DMTL pump electrical high
P2404-2F	DMTL noise fault
P2404-29	DMTL reference leak
P2405-00	DMTL reference current low
P2406-00	DMTL reference current high
P2450-00	DMTL COV stuck open
P2451-00	DMTL COV stuck closed
P240B-00	DMTL heater electrical low (open)
P240C-00	DMTL heater electrical high

Attempt To Replicate The Fault Using The "Fuel Leak Check" Forced Test

1. Record any DTCs that has been logged
2. Using the manufacturer approved diagnostic system, in the Recommendations  tab run the Fuel Leak Check  forced test
3. For the test to run the fuel level must be between 15% and 85%
4. During this procedure the engine must be off
5. The possible responses from the test and the associated DTCs are listed below
6. If again no fault is found it could suggest that the failure mode is a borderline condition (refer to section 3) or that it was caused by incorrect fitment of the fuel cap or the fuel filler neck is at fault therefore it is important not disturb the fuel cap
7. Disconnect purge pipe from the purge valve, observe the condition of connection (the seating and condition of the "O" ring) and then reconnect. Using the manufacturer approved diagnostic system, run Purge Valve Self Test  (to clean the purge valve) then run the Fuel Leak Check 
8. If the test failed, a smoke test is required to determine the cause of the leak
   NOTE: P240B & P240C are not included in the Fuel Leak Check  forced test (these monitors run at every ignition on and complete within 30 seconds)

   Response Description	ID	Equivalent DTC
   Function running: Reference leak measurement	1
   Function running: Rough leak measurement	2
   Function running: Small leak measurement	3
   Function running: 2nd ref leak measurement	4
   Function running: COV Cleaning	5
   Function aborted due to conditions: Vbatt conditions not correct (too high/ low)	11
   Function aborted due to conditions: Variation Ref. I (reference current) too high	12	P2404-29
   Function aborted due to conditions: DMTL electrical fault	13	P0447, P0448
   Function aborted due to conditions: Maximum diagnostic time exceeded	14
   Function aborted due to conditions: Crash detected	15
   Function aborted due to conditions: Refuel detected	20
   Function aborted due to conditions: Filler cap opened	21
   Function aborted due to conditions: Engine start	23
   Function aborted due to conditions: Noisy current measurement	24	P2404-2F
   Function aborted due to conditions: Ambient temp outside range	26
   Function aborted due to conditions: Ambient pressure outside range	27
   Function aborted due to conditions: Other conditions	29
   Function complete - Tight system, fault free	30
   Function complete - Fine leak detected	31	P0442
   Function complete - Rough leak detected	32	P0455
   Function complete - Module error	33	P2401, P2402, P2450, P2451, P2405, P2406, P2404-29
   Function complete - Medium leak detected	34	P0442, P0455

   Read The "Ranking values" To Determine How Far Away The Result Is From The Failure Threshold

9. When the Fuel Leak Check  forced test has completed the test results (known as ranking values) will be displayed
10. These should be compared against the limits shown in the table below
11. If the test result is borderline then there is a risk that a failure will occur at a later date (during customer usage of the vehicle)
12. To avoid this the vehicle should be carefully checked for any small leaks

Ranking Value	Normal Result For Tight System	Leak Failure Condition
Rough Leak (40 thou+)	0 > = 50	>= 128
Small Leak (20 thou+)	0 > = 60	>= 128

TRACE THE ROOT CAUSE OF THE FAULT

The list below provides some suggested actions to help trace the root cause of the fault

Each action should be followed up with a Fuel Leak Check  forced test (and ranking value check) in order to determine if any improvement has been made

DTC	Fault Description	Fault Rectification Actions after smoke test
P0442-00	DMTL small leak	1. Inspect / refit filler cap after smoke test (inspect filler neck for correct fitment to pocket so that filer neck protrudes) 2. Run engine at idle; Using the manufacturer approved diagnostic system, run Purge Valve Self Test  (to clean the purge valve) 3. Check that the DMTL module wiring connector has been installed correctly and that the seals around the connector body and individual wires are in good condition 4. Check all fuel system connections are correctly installed and secure 5. Visually inspect purge canister, purge pipes, fuel tank and filler neck for any obvious damage 6. Try isolating the purge valve by fitting a blanking plug to the purge pipe 7. Carry out a smoke test 8. Replace the DMTL module
P0447-00	DMTL COV electrical low (open)	1. Check fuse 2. Check that fuse fits tightly into the fuse holder 3. Check that the DMTL module wiring connector has been fitted correctly 4. Check wiring harness continuity between DMTL module and ECU connectors 5. Replace DMTL module
P0448-00	DMTL COV electrical high	1. Check wiring 2. Replace DMTL module
P0455-00	DMTL rough leak	1. Inspect / refit filler cap after smoke test (inspect filler neck for correct fitment to pocket so that filer neck protrudes) 2. Run engine at idle; Using the manufacturer approved diagnostic system, run "Purge Valve Self Test" (to help clean the purge valve) 3. Check that the DMTL module wiring connector has been installed correctly and that the seals around the connector body and individual wires are in good condition (surprisingly, this is a potential leakage path!) 4. Check all fuel system connections are correctly installed and secure 5. Visually inspect purge canister, purge pipes, fuel tank and filler neck for any obvious damage 6. Try isolating the purge valve by fitting a blanking plug to the purge pipe 7. Carry out a smoke test 8. Replace DMTL module
P2401-00	DMTL pump electrical low (open)	1. Check fuse 2. Check that fuse fits correctly into the fuse holder 3. Check that the DMTL module wiring connector has been fitted correctly 4. Check wiring harness continuity between DMTL module and ECU connectors 5. Replace DMTL module
P2402-00	DMTL pump electrical high	1. Check wiring 2. Replace DMTL module
P2404-2F	DMTL noise fault	Replace DMTL module
P2404-29	DMTL reference leak	Replace DMTL module
P2405-00	DMTL reference current low	Replace DMTL module
P2406-00	DMTL reference current high	1. Check for any blockages in the DMTL ventilation pipe & filter 2. Replace DMTL module
P2450-00	DMTL COV stuck open	Replace DMTL module
P2451-00	DMTL COV stuck close	Replace DMTL module
P240B-00	DMTL heater electrical low (open)	1. Check fuse 2. Check that fuse fits tightly into the fuse holder 3. Check that the DMTL module wiring connector has been fitted correctly 4. Check wiring harness continuity between DMTL module and ECU connectors 5. Replace DMTL module
P240C-00	DMTL heater electrical high	1. Check wiring 2. Replace DMTL module

Pre and 10MY Denso/Bosch PCM Systems 

• 1. Remove rear wheel arch liner to access fuel filler neck
• 2. On the fuel filler neck the DMTL filter will be visible as shown in picture. Unclip filter housing from fuel filler neck to gain better access to DMTL filter
• 3. Remove carefully the top of filter to expose filter and remove
• 4. Attach rubber adapter to tip of smoke machine nozzle to ensure tight seal to filter housing. Disconnect the purge pipe from purge valve; this will be an escape point for the smoke to exit
• 5. Allow tester to complete self-test and green READY light to turn ON 2. For best Tester performance; completely unwind Tester's supply hose
• 6. Press Smoke  on control panel to fill EVAP system with smoke vapor. The control panel Smoke  light will light indicating smoke production. The smoke setting is on a 15 minute timer. Pressing the Smoke  button again turns Tester off. It is normal for the flow meter ball, while in the smoke mode, not to be as steady as when it is in the Test  mode. Note: The pressure gauge is active only after smoke cycle is complete
• 7. Continue introducing smoke into the EVAP System until the flow meter's ball stops descending and this assures the system test pressure is met and smoke will appear from the purge pipe, then close off purge pipe with special tool (Test Adapter Hose/EVAP Port 310-142)

Pre 10MY Vehicles 

On pre 10MY DMTL systems, Using the manufacturer approved diagnostic system, select Measurement application  session then select the Recommendations  tab which will give you access to Datalogger  . Then select Engine systems  then select the Output state control  data-logger signal Engine output 1 - diagnostic module - tank leakage -change over valve active  which will close the system. Then select Engine output 1 - diagnostic module - tank leakage - pump active  this will pressurize the EVAP system

10MY vehicles 

On 10MY vehicles a smoke test application is available so therefore only smoke fill the system and then run the application

• 8. Follow the EVAP system path with the halogen light provided and looks for the smoke exiting the leak(s) or use the UV light provided and look for the dye deposited at the exact location of the leak(s)
• 9. Repair the leak(s) and perform the Fuel Leak Check  application again or smoke test to verify repair, as well as to make sure there are no additional leaks in the EVAP system

The UltraTraceUV® smoke solution's dye feature is especially helpful when the leak is in an area that is not readily visible, as on the top of the fuel tank or behind a panel. Once you gain access to the area of the leak, wear the yellow UV glasses and shine the UV light provided to identify the exact location of the leak(s). Smoke exiting a very small leak is even easier to see with lower pressure. If you encounter smoke leaking out of an area but find it difficult to pinpoint exactly where the source of the leak is; try reducing the pressure in the system being tested by turning the Tester OFF and allow the pressure to dissipate. The longer a particular leak is allowed to leak, the more fluorescent dye material will be deposited at that leak. With some vapor system leaks, the leak may only present itself under vacuum and not under pressure. If equipment permits, test the system in both states. Purge valve faults [P0441, P0444, P0458 and P0459] should all inhibit DMTL leak test and therefore need to be resolved prior to any DMTL issues. For this reason, when smoke testing the vapor system, it should be sufficient to enter the system at the connection up stream of the purge valve. If no leak is found then testing the remainder of the system up to the purge valve is recommended

Phase-One - (quantifying the leak) 

• 1. Connect the tester supply hose to vehicle EVAP system. > Refer to appropriate vehicle application
• 2. Determine if the vehicle's EVAP system you are testing is governed by a.020" (0.5 mm) or.040" (1 mm) acceptable leak standard. Press the appropriate calibration standard on the tester's control panel and observe the position of the flow meter ball. > This function automatically turns off in 10 seconds
• 3. Position the flow meter's pointer flag so that it aligns with the measurement observed in step 2 above. > This sets PASS / FAIL mark
• 4. Close vehicle's EVAP Vent Solenoid. > Refer to appropriate vehicle application

• 5. Press TEST on control panel and fill EVAP system. > This introduces 5-minutes of nitrogen gas
• 6. Look for flow meter ball to stop descending indicating that the vehicle system is full. > Fill time 1-4 minutes depending on system volume
• 7. Compare flow meter ball reading to pointer flag. > ABOVE flag = FAIL (go to Phase-Two). > BELOW flag = PASS (test complete)

Testing With Pressure and Vacuum Decay 

In addition to quantifying the leak with the Phase-One flow test, the Tester allows you the flexibility of testing the vehicle's EVAP system by using either Pressure Decay  or Vacuum Decay  methods. Below are instructions for performing both decay tests

Pressure-Decay Test 

At the completion of the Phase-one flow test, the EVAP system is fully pressurized, since the Phase-one test uses pressure to perform its flow test. Testing pressure decay with the Vacutec® 522B-J/LR is very simple. All you need to do is the following:

• 1. Allow tester to complete self-test and green READY  light to turn ON
• 2. Connect Tester supply hose to vehicle EVAP system
• 3. Close vehicle's EVAP Vent solenoid > Refer to appropriate vehicle application
• 4. Press VACUUM  switch on the tester control panel

  NOTE: The vacuum switch is on a 30-second timer, which should be sufficient time to draw the appropriate vacuum from the EVAP system. Press VACUUM switch again if additional time is required

• 5. After vacuum timer turns off, observe the vacuum gauge for any decay (loss of vacuum) indicating a leak in the EVAP system