Test Step 4. Disconnect the +5 V Sensors While Active Diagnostic Codes are Being Monitored

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TM 9-2320-312-24-2

Troubleshooting Section

3. If the problem is resolved with the test ECM,

Results:

reconnect the suspect ECM.

Yes The +5 V diagnostic code is still active. The

4. If the problem returns with the suspect ECM,

harness is the cause of the problem. Leave the

replace the ECM.

sensors disconnected. Proceed to Test Step 5.

No Disconnecting a specific sensor makes the

STOP.

+5 V diagnostic code no longer active.

No The +5 V diagnostic code is no longer

Repair: Perform the following diagnostic

active when the harness is disconnected. Either

procedure:

the harness or a sensor that is attached to the

harness is causing the problem. Reconnect the

1. Reconnect the sensor that is suspected of

ECM engine harness connector. Proceed to Test

causing the problem.

Step 4.

Test Step 4. Disconnect the +5 V Sensors

2. If the problem returns after the reconnection of

While Active Diagnostic Codes are Being

the sensor, disconnect the sensor.

Monitored.

3. If the problem disappears after the

disconnection of the sensor, replace the

A. Connect ET to the cab data link connector.

sensor.

B. Turn the ignition key switch to the ON position.

4. Clear all diagnostic codes.

C. Access the "Active Diagnostic Code" screen on

5. Verify that the repair eliminates the problem.

ET. Verify that one of the following diagnostic

codes is active:

STOP.

232-03 5 Volt Supply Above Normal (21)

232-04 5 Volt Supply Below Normal (21)

D. Disconnect the following sensors one at a time:

Boost pressure sensor J200/P200

Injection actuation pressure sensor J204/P204

Engine oil pressure sensor J201/P201

Atmospheric pressure sensor J203/P203

E. Wait for 30 seconds after each pressure sensor

is disconnected while ET is being monitored in

order to verify that the disconnection of a specific

sensor deactivates the +5 V diagnostic code.

Note: When the sensors are disconnected and the

ignition key switch is in the ON position, open circuit

diagnostic codes will be active or logged when the

+5 V diagnostic codes are no longer active. This is

normal. Clear these diagnostic codes after this test

step is completed.

Expected Result:

The original +5 V diagnostic code remains active.