Pinpoint Test A: The Smart Junction Box (SJB) Does Not Respond To The Diagnostic Tool

WARNING: This page is about a different car, the 2004 Ford Ranger. However, it is still accessible from the selected car via links, so may be relevant.

A1 CHECK THE SJB CONNECTORS FOR DAMAGE
- Key in OFF position.
- Disconnect: SJB C2280d.
- Inspect the SJB C2280d connector for damage.
- Is the SJB C2280d connector OK?
1. Yes : GO to A2.
2. No : REPAIR the SJB C2280d connector. CARRY OUT the data link diagnostics test.
A2 CHECK ISO COMMUNICATION CIRCUIT 70 (LB/WH) BETWEEN THE DLC C251 AND THE SJB C2280d FOR AN OPEN
- Measure the resistance between the DLC C251 pin 7, circuit 70 (LB/WH), harness side and the SJB C2280d pin 7, circuit 70 (LB/WH), harness side.
  
  Fig 1: Checking ISO Communication Circuit 70 (LB/WH) Between DLC C251 & SJB C2280D For An Open
  Courtesy of FORD MOTOR CO.
- Is the resistance less than 5 ohms?
1. Yes : GO to A3.
2. No : REPAIR the circuit. CARRY OUT the data link diagnostics test.
A3 CHECK FOR CORRECT SJB OPERATION
- Disconnect all the SJB connectors.
- Check for:
  - Corrosion
  - Push-out pins
- Connect all the connectors and make sure they seat correctly.
- Key in ON position.
- Operate the system and verify the concern is still present.
- Is the concern still present?
1. Yes : INSTALL a new SJB. REFER to MULTIFUNCTION ELECTRONIC CONTROL MODULES . CARRY OUT the data link diagnostics test.
2. No : The system is operating correctly at this time. Concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the self-test. CARRY OUT the data link diagnostics test.