Replaced EVAP vent valve - clearing code?

[Jetmugg]

I recently developed a code p0446 - EVAP vent valve.

 

Just today, I disconnected the battery and replaced the vent valve and charcoal canister. The lines have previously been cleared of all charcoal residue.

 

After replacing the valve and canister, and hooking up the battery, I expected the SES light to be off. However, to my surprise, I still have the light.

 

Does this code - 0446 - need to be cycled though its normal diagnostics before it turns the light off, or am I possibly missing something? I know that the EVAP vent valve only opens and closes periodically, but does it need to cycle befor the SES light goes off?

 

SteveM

[k9sar]

typically, a CEL code needs to be cleared either manually (via tool) or by the vehicle operating for a number of times with good readings. I don't know the R50's specifically.

[PwninOBrien]

This should do . The easy method really is easier, so I would try that first.

 

RESET ECU

 

1. Confirm that accelerator pedal is fully released, turn ignition switch “ON” and wait 3 seconds.

 

2. Repeat the following steps (2a and 2b) procedures quickly five times within 5 seconds.

 

2a. Fully depress the accelerator pedal (HARD).

2b. Fully release the accelerator pedal.

 

3. Wait 7 seconds, fully depress the accelerator pedal and keep it for approx. 10 seconds until the CEL starts blinking.

 

4. Fully release the accelerator pedal (while the CEL is still blinking).

 

5. Wait about 10 seconds.

 

6. Fully depress the accelerator pedal and keep it for more than 10 seconds.

 

7. Fully release the accelerator pedal (The CEL light will continue to blink).

 

8. Turn ignition switch to “OFF” position and now you can start the car. The CEL light should be gone.

 

If the CEL light continues to remain ON, repeat the above steps. Timing is EXTREMELY critical to resetting the ECU.

 

EASY METHOD

 

1. Ignition "ON", count to 3.

 

2. Depress/Release pedal 5 times...hard and fast.

 

3. Count to 10 (not 7!) and fully depress pedal

 

4. Count to 12 (SES should be blinking), release pedal

 

5. Count to 10, depress pedal

 

6. Count to 10, release pedal.

 

7. Turn off ignition, then start engine. Done!

[carwilef7]

WAY easier method with less timing involved - turning the screw on the ECU.

 

On my XE, the ECU is located to the right of the steering column. The screw is on the far upper right side of it, presumably to keep people from idly messing with it.

 

Pull the lower dash cover from under the column - two screws, plus one in the kick panel to get to one of the dash cover ones. Remove any wiring connectors so you can get the cover out of the way.

 

Two nuts hold the ECU onto a bracket - remove them and slide the ECU back (toward the front of the truck) and down out of its upper clip. You may have to carefully rotate the ECU to get it so you can see the screw. Mine had a clear plastic label over it, making it impossible to feel with fingers. Make sure you have located the screw with the curved arrow mark near it.

 

Turn the key to "on" but don't start the truck. Using a flat blade screwdriver, rotate the screw fully clockwise and hold it for at least two seconds, then turn it all the way back counter-clockwise - you can now read the codes by counting the flashes from the CEL/SES/MIL light.

 

To clear it, turn the screw fully clockwise again and hold for two seconds, then turn it back. Turn the key to "off". Now start the truck and the CEL/SES/MIL light should be off - unless there's another issue someplace that wasn't fixed before reset.

 

Once you know where the screw is, you can probably use a flat driver bit (for a drill) and reach up there blind without removing the ECU again. To reinstall the ECU, make sure it slides into the clip at the top, re-align the studs with the bracket, and tighten the nuts. Then re-install the lower dash cover and you're done!