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Home >> Jeep >> 2019 >> Grand Cherokee Laredo, AWD, Full Time T/Case Control >> Repair and Diagnosis >> External Pages >> Different car >> Section 378 ((Security Gateway Module (SGW) Electrical Diagnostics)) >> Standard Procedure >> Communication Diagnostic Procedure >> Possible Causes
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Possible Causes

WARNING: This page is about a different car, the 2021 Jeep Grand Cherokee L. However, it is still accessible from the selected car via links, so may be relevant.
Possible Causes
SYSTEM OR ELECTRONIC CONTROL UNIT (ECU) VOLTAGE DTC(S)
SERVICE BULLETIN(S)
SOFTWARE UPDATE(S)
VEHICLE CONFIGURATION DTC(S)
COMMUNICATION RELATED DTC(S)
NON U-CODE DTC(S)
ECU POWER SUPPLY (FUSED B+ OR IGNITION) CIRCUIT(S) OPEN OR SHORTED TO GROUND
ECU GROUND CIRCUIT(S) OPEN OR HIGH RESISTANCE
CAN BUS CIRCUIT(+/-) OPEN OR HIGH RESISTANCE
POOR CONNECTION(S) AT CAN BUS ECU HARNESS CONNECTOR(S)
CAN BUS ECU