What would cause the epc light to constantly come on in a '01 jetta 1.8 turbo?

EPC light should have nothing to do with the shift interlock,(EPC is traction control) should be a small cap or plug on the console, near the shifter that has the interlock disengage button,usually done with a key,check shift interlock in the owners manual.

Check the handbrake (e-brake) switch, move the handle up and down vigorously. If the cables are sticking, the handle may not go all the way down, sending the signal that the e-brake is still engaged.

key in drivers door. lock. unlock.

take to dealer i believe the light stands for electronic powering steering. this would be a safety issue

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What ,year audi and model? EPC LIGHT PO299. let me see if i can find out with out year and model.
okay, if your car has turbo then this is correct, po299 low boost.
this may be caused by a bad diverter valve on the turbo, if you remove it and look ay diaphram for any cracks or splits in rubber, if it is then replace it ,check for an update valve at dealer.
there are other thing that can cause this code but start with that. a loose hose for the turbo can cause this code or bad turbo or clogged converter, or oil sulge problem.

When was the last time you changed your Air filter( A dirty filter can put MAF sensor out of range). How about the fuel filter (Fuel starvation). These filters should be changed every 30,000 miles . It is normal for all of the dash lights to come on if the engine stops running. Is the Jetta a Diesel or Gas. Perform The OBDII scan again to see if current faults are present. Do the cheapest fixes first. Also check oil often. The low oil sensor will trigger engine shut down if more than 1 quart low

EPC light is on and dont exelorade

The EPC Light is "Electronic Power Control." You should have your vehicle scanned with an electronic diagnostic tool to find out what is causing the light to come on.

hallo
EPC means Electronic Pedal Control. Fly-by-wire for your gas pedal--instead of a mechanical cable that pulls an accelerator linkage on the engine, there's an electronic device on the gas pedal, an electronic device on the throttle body and a wire between them.
You should check the sistem with diagnostic tool.
Marko

Take it to the dealer, the EPC warning light - and even more the failsafe run which doesn't allow you drive faster than 20mph) is an indication of serious motor troubles. They can read the ECU faultcodes, which should be a good startingpoint for troubleshooting the cause ...

You could do some basic troubleshooting like checking the air filter, the oil level, the spark plugs, etc. You didn't fill it up with bad gas, did you ? And does the engine make strange noises/vibration when running idle ? In case you fixed some obvious cause, you can dis- and reconnect the battery to erase the engine's faultcode. If it's not fixed, the EPC (and failsafe run) will simply come on again.

My advice would be not to drive it untill it's fixed to prevent more potential damage.