Mazda DTC P2502 Diagnostic

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.
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

 

Diagnostic procedure

 
 

STEP

 

 

INSPECTION

 

 

ACTION

 

1
VERIFY FREEZE FRAME DATA HAS BEEN RECORDED

• Has FREEZE FRAME DATA been recorded?

Yes

Go to the next step.

No

Record the FREEZE FRAME DATA on the repair order, then go to the next step.

2
VERIFY RELATED REPAIR INFORMATION AVAILABILITY

• Verify related service repair information availability.

• Is any related repair information available?

Yes

Perform repair or diagnosis according to the available repair information.

• If the vehicle is not repaired, go to the next step.

No

Go to the next step.

3
INSPECT BATTERY

• Turn the ignition switch to off.

• Inspect battery.

• Is battery normal?

Yes

Go to the next step.

No

Replace battery, then go to Step 7.

4
INSPECT POOR INSTALLATION OF GENERATOR TERMINAL

• Turn the ignition switch to off.

• Inspect for looseness of generator terminal B installation nut.

• Is the nut loose?

Yes

Tighten generator terminal B installation nut, then go to Step 7.

No

Go to the next step.

5
INSPECT POOR INSTALLATION OF BATTERY POSITIVE TERMINAL

• Inspect for looseness of battery positive terminal.

• Is the terminal loose?

Yes

Connect battery positive terminal correctly, then go to Step 7.

No

Go to the next step.

6
INSPECT BATTERY CHARGING CIRCUIT

• Disconnect the generator terminal B.

• Measure the voltage between the generator terminal B (wiring harness-side) and the body ground.

• Is the voltage B+?

Yes

Go to the next step.

No

Repair or replace wiring harness between the generator terminal B and the battery positive terminal, then go to the next step.

7
VERIFY TROUBLESHOOTING OF DTC P2502 COMPLETED

• Make sure to reconnect all connectors.

• Clear DTC from memory using WDS or equivalent.

• Start the engine.

• Is same DTC present?

Yes

Replace PCM, then go to the next step.

No

Go to the next step.

8
VERIFY AFTER REPAIR PROCEDURE

• Perform “After Repair Procedure”.

• Is there any DTC present?

Yes

Go to applicable DTC troubleshooting.

No

Troubleshooting completed.