I have a 2003 Ford Explorer. Recently I noticed thsat a warning light "Service Engine Soon" illuminated on my dash and wont go away. I've never seen this before and Ive owned the car since 2003. What'

The wrench warning light on Ford vehicles is the powertrain malfunction indicator light. When it illuminates, it means that the computer has detected an issue with your vehicle's powertrain or four-wheel-drive system.

A powertrain malfunction light should be taken seriously, as allowing a serious issue to persist can lead to costly repairs to your engine, transmission, or drivetrain in the long run. You should consider having the car towed straight to an authorized dealer rather than driving if you notice any changes in your vehicle's performance like engine shaking or reduced power. In cases where you are towing a heavy load and/or driving up a steep grade, a powertrain malfunction light may be telling you to ease off to avoid overheating. If the problem resolves itself the warning may go away.
It's possible that your vehicle might enter Fail-Safe Mode shortly after the powertrain malfunction light illuminates. Fail-Safe Mode automatically limits engine power so that you can safely maneuver your vehicle off the road without causing any further damage to your vehicle's components. If this happens, you should only continue to drive as long as necessary to bring your vehicle to rest in a safe location and seek immediate repairs.

If your Ford dashboard warning light is orange or red, this can be a signal that your vehicle is experiencing a problem that should be looked at very soon. Use Ford's quick and easy dashboard warning light reference sheet to determine what is happening with your vehicle.
When a light is yellow, your Ford is trying to tell you that service may be required, or at the least, you should have a technician decipher the warning lights meaning. When a Ford dashboard warning light is green or blue, they are simply telling you that one of your Ford's features is being used, or has been activated.

Service Engine Soon

If the Service Engine Soon indicator light stays lit after you've started the engine, the On Board Diagnostics system (OBD) has detected a malfunction of the vehicle emissions control system. Contact your authorized dealer as soon as possible.
If indicator light is blinking, an engine misfire may be occurring, which could damage your catalytic converter. Drive in a moderate fashion (avoid heavy acceleration and deceleration), and have your vehicle serviced immediately.*
The Service Engine Soon indicator light illuminates when the ignition is first turned on (prior to engine start) in order to test the bulb, as well as indicate whether the vehicle is ready for Inspection/Maintenance (I/M) testing.
Normally, the Service Engine Soon light will stay on until the engine is cranked, then turn itself off if no malfunctions are present. However, if after 15 seconds this light blinks eight times, it means that the vehicle is not ready for I/M testing.Check this link out Gary.
https://owner.ford.com/how-tos/vehicle-features/dashboard-instrument-cluster/warning-lamps-and-indicators.html

There isn't one ! This vehicle relies on serial data communication . The PCM sends an message on the data bus to the microprocessor inside the instrument cluster . The PCM controls the operation of the charging system warning indicator in the instrument cluster. The PCM is therefore responsible for turning the warning indicator off after the engine is started and illuminating it under fault conditions (when the generator is not generating the correct amount of current with the engine running). The warning indicator will also be illuminated by the PCM at key ON engine OFF, and stall conditions.
Charging System Warning Indicator
The instrument cluster receives the charging system status from the PCM over the SCP or CAN communication network. The PCM controls the charging system and the charging system warning indicator. The PCM is therefore responsible for turning the lamp off once the system is running and illuminating it under fault conditions (including stall conditions).
How to Diagnose Controller Area Network CAN Your best bet would be to take your vehicle to a qualified repair shop .

You may have to get the key reprogramed. The ECU is not reading the key, resulting in Anti-theft mode (Disable Ignition). You need the Dealer and OBDII Test .

Abs is bad sensor in hub bearing,engine light you need obd 2 scanner to read and reset code,

The first thing to do is to have the ABS and engine computers scanned for trouble codes.
The problem with the check engine light could also turn on the ABS and traction control lights. Or it could be different issues.
The gas gauge being out of calibration could be the float in the gas tank or the gauge on the dash. I doubt that problem is related to the warning lights.

Yes it may be the wires are shorting or its actually the problem with instrument cluster.
Also get the vehicle scanned for any error codes stored in computer this will confirm whether is short circuit issue or actual problem:------
I suggest you few help links with accurate solutions to refer/go through:----Click the link below:------

Battery and brake Warning lights on Dash
http://alltypesofpartsreplacing.blogspot.com/2012/10/battery-and-brake-warning-lights-on-dash.html
--------------2002 Ford Windstar: Brake Warning Light ON dash? http://schematicsdiagram.blogspot.in/2012/06/2002-ford-windstar-brake-warning-light.html
-------------ABS & Brake warning lights remains steady on dash? http://schematicsdiagram.blogspot.com/2011/12/abs-brake-warning-lights-remains-steady.html
-----------Chevrolet Tahoe Hood open warning on dash and alarm sounds? http://schematicsdiagram.blogspot.com/2011/12/chevrolet-tahoe-hood-open-warning-on.html
-----------2005 Chevy Impala: Service Vehicle Soon Warning Light? http://whoisbyme.blogspot.in/2012/06/2005-chevy-impala-service-vehicle-soon.html -------------- Malfunction Indicator Light ON http://whoisbyme.blogspot.in/2012/06/malfunction-indicator-light-on.html
-----------Car Runs Fine But Check Engine light is ON?

http://whatisbyme.blogspot.in/2012/05/car-runs-fine-but-check-engine-light-is.html

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Check engine light with codes P2195 and P2197?

http://howtobyme.blogspot.in/2012/01/check-engine-light-with-codes-p2195-and.html

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How to Read Codes from Check Engine Light? http://schematicsdiagram.blogspot.com/2011/12/how-to-read-codes-from-check-engine.html
-------------These will help.Thanks.

sounds like it may be the catalytic converter

According to the 2003 Ford TaurusOwners Manual:

"Brake system warning light: To confirm the brake system warning light is functional, it will
momentarily illuminate when the ignition is turned to the ON position when the engine is not running, or in a position between ON and START,
or by applying the parking brake when the ignition is turned to the ON position. If the brake system warning light does not illuminate at this
time, seek service immediately from your dealership. Illumination after releasing the parking brake indicates low brake fluid level and the brake
system should be inspected immediately by your servicing dealership."

In short, as your brake linings (pads and shoes) wear out, the brake fluid level in the reservoir goes down.

You're probably right at the point where the level gets low enough to turn on the warning only under specific circumstances (cornering? hard braking?).

You can top off the fluid for the short term, but you should have your brakes inspected fairly soon.

key on engine off, does the airbag light illuminate then go out? or never seen? this is usually that the air bag light is not functioning as should so gives you an audible warning......