Engine-Codes - Jeep - P1521 Jeep

P1521 Jeep Code - Incorrect Engine Oil Type

- Code Popularity: 41,387 Views
- Repair Importance Level: 3/3
- Repair Difficulty Level: 2/3
Table of contents
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What are the Possible Causes of the DTC P1521 Jeep?

NOTE: The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.
  • Incorrect engine oil viscosity
  • Incorrect oil type
  • Oil contamination
  • Faulty Engine Oil Pressure Sensor
  • Reprogram Powertrain Control Module (PCM)

Code Tech Notes

This Diagnostic Trouble Code (DTC) may set in high ambient temperature conditions when the correct oil type (viscosity) is being used in the Engine. If correct oil viscosity is used, but the code keeps coming back, reprogramming (refreshing) the Powertrain Control Module (PCM) will take care of the problem.

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How to Fix the DTC P1521 Jeep?

Check the 'Possible Causes' listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector pins.

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What is the Cost to Diagnose the Code?

Labor: 1.0

The cost to diagnose the P1521 Jeep code is 1.0 hour of labor. The diagnosis time and labor rates at auto repair shops vary depending on the location, make and model of the vehicle, and even the engine type. Most auto repair shops charge between $75 and $150 per hour.

What are Code Possible Symptoms?

  • Engine Light ON (or Service Engine Soon Warning Light)

What Does the P1521 Jeep Code Mean?

Using the oil pressure, oil temperature and other vital engine inputs the Powertrain Control Module (PCM) can determine the engine oil viscosity. Incorrect viscosity will affect the operation of the MDS by delaying cylinder activation. The Diagnostic Trouble Code (DTC) will set when the PCM has detected an incorrect engine oil viscosity.

P1521 Jeep Code - Incorrect Engine Oil Type

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