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

STEP

INSPECTION

ACTION

1

• 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 Service Bulletins and/or on-line 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

• Turn the ignition switch off.

• Inspect the battery.

• Is the battery normal?

Yes

Go to the next step.

No

Replace the battery, then go to Step 7.

4

• Turn the ignition switch off.

• Inspect for looseness of generator terminal B installation nut.

• Is nut loose?

Yes

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

No

Go to the next step.

5

• Inspect for looseness of battery positive terminal.

• Is the terminal loose?

Yes

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

No

Go to the next step.

6

• Disconnect the generator terminal B.

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

• Is the voltage B+?

Yes

Go to the next step.

No

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

7

• Make sure to reconnect all connectors.

• Clear the DTC from the PCM memory using the M-MDS.

• Start the engine, or perform the KOER self-test with M-MDS.

  (See KOEO/KOER SELF TEST [LF].)

• Is the same DTC present?

Yes

Replace the PCM, then go to the next step.

(See PCM REMOVAL/INSTALLATION [LF].)

No

Go to the next step.

8

• Perform “AFTER REPAIR PROCEDURE”.

  (See AFTER REPAIR PROCEDURE [LF].)

• Is there any DTC present?

Yes

Go to the applicable DTC inspection.

(See DTC TABLE [LF].)

No

Troubleshooting completed.