Safety Warning

DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.

2006 Mazda MX-5 Miata BaseFACTORY OEM SERVICE PROCEDURE

DTC P2502: Notes

DETECTION CONDITION AND POSSIBLE CAUSE (DTC P2502)

DTC P2502

Charging system voltage problem

DETECTION CONDITION

PCM judges generator output voltage is above 17 V or battery voltage is below 11 V during engine running.

Diagnostic support note

This is a continuous monitor (Other).
The MIL does not illuminate.
PENDING CODE is available if the PCM detects the above malfunction condition during the first drive cycle.
FREEZE FRAME DATA is available.
The DTC is stored in the PCM memory.

POSSIBLE CAUSE

Open circuit between generator terminal B and battery positive terminal
Battery malfunction Generator malfunction
PCM is poorly connected PCM, generator and/or battery are poorly connected

Courtesy of MAZDA MOTORS CORP.

Factory Service Tools

Use the Manual With the Right Hardware

Pair factory procedures with proven DIY tools so the instructions are easier to execute.

Disclosure: Verified tool recommendations may earn an affiliate commission at no cost to you.

Shop Manual-Ready Tools Compare Repair Quote Quote Shield Pro

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

• You smell fuel, burning insulation, or see smoke.
• Brakes feel soft, pull hard to one side, or make grinding noises.
• The engine overheats, stalls repeatedly, or misfires under load.
• You are missing required tools, torque specs, or safe lifting equipment.
• You are not confident in the next step or safety outcome.