How do i reset my diesel filter light - 2006 Mitsubishi L200 2.5

no maker ,model, year or engine told.
just, I guess diesel fuel wet.
the wet sensor needs to be fully dried out. (use heat gun? air dryer)
for a reset , click reset on the scan tool
or pull battery net lug for 15minutes +

Unfortunately this is a well known issue and well documented.

https://www.google.com/search?q=2010+Jaguar+XF+3+liter+Diesel.+Water+in+diesel+warning+light

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P2002 - Diesel Particulate Filter Efficiency Below Threshold (Bank 1)
Description: The powertrain control module(PCM) monitors the efficiency of the diesel particulate filter for a concern. The efficiency of the filter is determined by the amount of restriction in the filter for a certain exhaust flow rate. The diesel particulate filter is preconditioned for 5,000 km (3,107 miles) before the PCM begins to monitor the level of restriction. The test fails when the measured level of restriction is less than the expected level calculated by the PCM. Possible Causes:

• Dirty air cleaner element
• Recent manual or thorough diesel particulate filter regeneration
• Aftermarket accessories and performance modifications
• Modified tailpipe
• Exhaust leaks before or near the diesel particulate filter pressure sensor
• Leaks in the diesel particulate filter pressure sensor connecting hose
• Damaged diesel particulate filter

Diagnostic Aids: Check for leaks in the exhaust system. Check for aftermarket exhaust accessories and performance modifications that decrease the exhaust restriction. If a new diesel particulate filter was recently installed, verify the diesel particulate filter parameter reset procedure was carried out.

you are going to have to plug in a diagnostic reader and find out what the problem is or to shut off the light . You could also drive it for 300KM and it should reset itself

Just my 2 bits, go through a spring cleaning checklist. Plugs could be fouled up, fuel could be contaminated, you already did the filters. Do you have it chipped or programed? Change the exhaust lately? Do you have the code number? Autozone will scan it for you for free, tell you the code number. Again, just my 2 bits.

Change the diesel filer element.
Unplug the only connecter on filter housing.
Turn the ignition key to on position.
Go back and plug in the connector after more than five seconds.
The light should go off

Remove the key from the ignition but keep it handy. Important: Disconnect the negative terminal of the battery for longer than 90 seconds to prevent the risk of having the airbags deploy! Replace the diesel filter (Follow the instructions that can be found in Toyota service manuals (search www). Remove the diesel filter sensor cable (the one on top of the filter assembly). Make sure the new O-rings seat properly. Close the filter assembly by turning the locking ring until it clicks. Bleed the filter assembly by pushing the little plunger thing on the top of the assembly until pumping becomes difficult. Connect the negative back onto the battery. Insert the key in the lock and turn until the dashboard warning lamps come on, but do not start the car yet. Within 3 to 60 seconds of doing this re-connect the diesel flter sensor cable. The light should be extinguished. Obviously there could be another problem causing the light to remain on (not flashing - steady on). If the light is flashing, then you have water in the system and should follow the answer supplied elsewhere by someone else to drain the water. Now start the car and enjoy clean diesel fuel driving. You should really not wait for the light to come on steady before chnaging the filter. Some fanatics believe every 10,000km is the longest you should wait, but this depends on fuel quality, low or high sulfur content, etc. Rather do it more frequently than having to buy new injectors.

Probably replacing the fuel filter. There may be a switch that needs to be pressed to reset the fuel filter light as well.

That light indicates that it is time to replace your air filter. After replacing the filter you will want to reset the lamp. On the air filter housing is a filter indicator. It is a small (2" round) cylinder with red, yellow and blue colors on it, as well as 2 wires. Push in the rubber yellow cap on top of the cylinder until you feel a snap and see the yellow plunger in the cylinder move. This should reset the light.
I hope this helps

another bane of my life a renault ?? diesel or petrol if diesel their is a tap on the bottom of the filter to let any condensate out that can build up in the filter ,undo the tap and let it drain a bit till diesel comes out .