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 P2507: Notes

DETECTION CONDITION AND POSSIBLE CAUSE (DTC P2507)

DTC P2507

PCM B+ voltage low

DETECTION CONDITION

The PCM monitors the voltage of back-up battery positive terminal. If the PCM detects battery positive terminal voltage below 2.5 V for 2 s , the PCM determines that the backup voltage circuit has a malfunction.

Diagnostic support note

This is a continuous monitor (CCM).
The MIL illuminates if the PCM detects the above malfunction condition during the first drive cycle.
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 in wiring between battery positive terminal and PCM terminal 1BA
Short to ground in wiring harness between battery positive terminal and PCM terminal 1 BA
Poor connection of PCM connector
PCM malfunction

Courtesy of MAZDA MOTORS CORP.

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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.