After the code is read, it can be Googled to find the problem.
The steps are simple by cycling the key from Off to On three times, and the code will flash once on the dashboard LED.
Do not start the vehicle; only turn the key to the On position.
How To Check Engine Light Codes on a Jeep Wrangler Without a Scan Tool
- Turn the Key from OFF to ON three times.
- The last turn of the key should be in the ON position.
- The code will show for only a moment and flash P-done before going back to normal.
Typing P0520 into Google shows that it is an Engine Oil Pressure Sensor.
This method may not work for all Wranglers, and there are many low-cost scanners that can give the codes along with more information.
Most automotive stores will also do a free scan and give the code; if a scanner is not available, be sure to call a store first.
If this method works for you, let us know in the comment below, as it is a good quick way to troubleshoot a jeep in a pinch.