P3900 OBD-II: Reserved For Future Use

P3900 Severity

Moderate

Will P3900 go away on its own?

Once the vehicle's onboard system no longer detects the issue, most codes will disappear on their own. If your vehicle still has this code, however, it should be properly diagnosed to avoid a more serious problem.

For a proper diagnosis, RepairPal Certified shops have the equipment, tools, and expertise.

Moderate severity codes might not threaten the vehicle's safety or functionality immediately, but you should still get it diagnosed within a reasonable time frame to keep your car running well.

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OBD II Fault Code

OBD II P3900

OBD-II Code Reserved For Future Use is defined as a Reserved For Future Use

OBD Code Resources

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P3900 OBD-II: Reserved For Future Use

Will P3900 go away on its own?

Need a P3900 diagnosis? Trust our experts.

OBD II Fault Code

OBD Code Resources

Need a P3900 diagnosis? Trust our experts.

Ask our experts about P3900.

Other OBD-II Codes

OBD II Fault Code