2007 Ford Expedition 4WDFACTORY OEM SERVICE PROCEDURE

Smart Junction Box (SJB)

SMART JUNCTION BOX (SJB) DIAGNOSTIC TROUBLE CODE (DTC) LIST

DTC Description Perform Test
B1320 Driver Door Ajar Circuit Open Go to Pinpoint Test C .
B1328 Passenger Door Ajar Circuit Open Go to Pinpoint Test C .
B1331 Decklid Ajar Rear Door Circuit Failure Go to Pinpoint Test C .
B1336 Door Ajar RR Circuit Open Go to Pinpoint Test C .
B1572 Door Ajar LR Circuit Go to Pinpoint Test C .
B1688 Lamp Dome Input Circuit Short to Ground Go to Pinpoint Test C .
B2077 Liftgate Ajar Circuit Failure Go to Pinpoint Test C .
B2A35 Interior Lighting Output Circuit Open If the courtesy lamps are inoperative, go to Pinpoint Test A .
If the courtesy lamps stay on continuously, go to Pinpoint Test C .
B2A36 Interior Lighting Output Circuit Short to Ground Go to Pinpoint Test A .
B2A39 Puddle Lamp Output Circuit Open Go to Pinpoint Test J .
B2A3A Puddle Lamp Output Circuit Short to Ground If the puddle lamps are inoperative, go to Pinpoint Test J .
If the puddle lamps are always on, go to Pinpoint Test L .
Factory Service Tools

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.