My 2003 Lincoln Aviator emissions light is on and I failed inspection because of it. How can I pass inspection and fix this emissions problem? The inspection code given to me was PO420???

Lincoln Aviator drive light flashing Questions & Answers ...

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Lincoln Aviator cars & trucks drive light flashing questions and answers. ... 2003aviator check engine on why? car has brand 2003 aviator check engine is on ..

This lamp is yellow it is the check engine light for your emissions control ther is plug under the dash in drivers seating area 16 pin connector called a DCL Data Communications Link with a scanner you can retrieve trouble codes for repair.

Google your codes- to find out the system
with the fault & what it is

On the Lincoln Aviator there's a set of fuses under the dash of the vehicle. One set has to be dropped to get to the flasher fuse.

Here is a web site that will tell you in detailed instructions on how to replace your taillight on your 2003 Lincoln Aviator: http://www.ehow.com/how_2631_replace-tail-brake.html

You're going to have to have someone visually inspect it. There are dozens of possibilities and we can't honestly give you a fair assessment. Have it looked at by a competent shop.

Yes, there is a switch on the brake pedal that could have been knocked loose or broken. There is a solenoid lock on the shifter lever in the transmission console. Here is a big post on it from a paid advice sight. https://www.justanswer.com/ford-lincoln/3ohnl-2003-lincoln-aviator-frequently-locks-park-gear.html

sounds like solinod is stuck

If there is an Auto Zone around your area, have the truck scanned for the DTC codes which is causing your idle problem. There are to many things that can cause your trucks idle to be rough. Once you have it scanned, we can address the issue and have your truck running 100% again. Auto Zone scan free of charge and can give you the step by step instructions to repairing and replacing the parts needed. Good luck and keep me posted, be glad to help. 

U must crawl under the front bumper, the lights come out from the rear.