Smart Junction Box (SJB)

SMART JUNCTION BOX (SJB)

Inspection and Verification

1. Verify the customer concern.

2. Visually inspect for obvious signs of mechanical or electrical damage.

Visual Inspection Chart





3. If an obvious cause for an observed or reported concern is found, correct the cause (if possible) before proceeding to the next step.

NOTE:Make sure to use the latest IDS or equivalent tester software release.
4. If the cause is not visually evident, connect the IDS or equivalent tester to the data link connector (DLC).

NOTE:The vehicle communication module (VCM) LED prove out confirms power and ground from the DLC are provided are provided to the VCM.
5. If the IDS or equivalent tester does not communicate with the VCM:

- Check the VCM connection to the vehicle.
- Check the IDS or equivalent tester connection to the VCM.
- See Communications Network. No power to the IDS or equivalent tester or to the diagnose no communication with the IDS or equivalent tester.

6. If the IDS or equivalent tester does not communicate with the vehicle: See Communications Network. No response from the powertrain control module (PCM).

7. Carry out the network test

- If the IDS or equivalent tester responds with no communication for one or more modules, see Communications Network.
- If the network test passes, retrieve and record continuous memory diagnostic trouble codes (DTCs).

8. Clear the continuous DTCs and carry out the self-test diagnostics for the SJB.

NOTE:Before carrying out the on-demand self test, make sure that the ignition is in RUN, all the door are closed, the brake pedal is not pressed, the transmission is in NEUTRAL (automatic transmissions) and the clutch pedal is not pressed (manual transmissions).
9. If the DTCs retrieved are related to the concern, see Smart Junction Box (SJB) Diagnostic Trouble Code (DTC) Index.

10. If no DTCs related to the concern are retrieved, see - Symptom Related Diagnostic Procedures.