Ranger 2WD L4-2.3L (2009)
Body Control Systems: Initial Inspection and Diagnostic Overview
Inspection and Verification
Smart Junction Box (SJB)
Inspection and Verification
1. Verify the customer concern.
2. Visually inspect for obvious signs of electrical damage.
3. If an obvious cause of an observed or reported concern is found, correct the cause (if possible) before proceeding to the next step.
4. NOTE: Make sure to use the latest scan tool software release.
If the cause is not visually evident, connect the scan tool to the Data Link Connector (DLC).
5. NOTE: The Vehicle Communication Module (VCM) prove-out confirms power and ground from the DLC are provided to the VCM.
If the scan tool does not communicate with the VCM:
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Check the VCM connection to the vehicle.
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Check the scan tool connection to the VCM.
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Refer to Information Bus, No Power To The Scan Tool, to diagnose no power to the scan tool.
6. If the scan tool does not communicate with the vehicle:
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Verify the ignition key is in the ON position.
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Verify the scan tool operation with a known good vehicle.
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Refer to Information Bus to diagnose no response from the PCM.
7. Carry out the network test.
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If the scan tool responds with no communication for one or more modules, refer to Information Bus.
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If the network test passes, retrieve and record the continuous memory DTCs.
8. Clear the continuous DTCs and carry out the self-test diagnostics for the SJB.
9. If the DTCs retrieved are related to the concern, go to DTC Charts. For all other DTCs, refer to the Diagnostic Trouble Code (DTC) Chart See:
Diagnostic Trouble Code Descriptions.
10. If no DTCs related to the concern are retrieved, GO to Symptom Chart. See: Symptom Related Diagnostic Procedures
Principles of Operation
Smart Junction Box (SJB)
Principles of Operation
NOTE: The Smart Junction Box (SJB) is also known as the Generic Electronic Module (GEM).
The SJB is a multifunction module that controls many of the vehicle systems. Several SJB functions utilize hardwired inputs and/or outputs. The SJB
controls the following hardwired functions, using the corresponding inputs and outputs:
