Tuesday, December 3, 2019

2019 Cadillac Truck Escalade AWD V8-6.2L Diagnostic Instructions Page 396


5. Ignition OFF, disconnect the X1 harness connector at the BCM, test for less than 1.0 volt between the following circuit terminals of the BCM



and ground.



* Ignition key resistor signal terminal 4



* Off/Run/Crank voltage terminal 2



* Accessory voltage terminal 21



* Ignition 1 voltage terminal 14



锟斤拷 If greater than specified, test the circuit for a short to voltage.



6. Test for less than 1.0 ohm of resistance between the BCM and the ignition switch on the following circuit terminals.



* Ignition key resistor signal, BCM terminal 4 and ignition switch terminal 6



* Off/Run/Crank voltage, BCM terminal 2 and ignition switch terminal 5



* Accessory voltage, BCM terminal 21 and ignition switch terminal 3



* Ignition 1 voltage, BCM terminal 14 and ignition switch terminal 2



锟斤拷 If greater than specified, repair the circuit for open/high resistance



7. Test for infinite resistance between the ignition key resistor signal circuit terminal 4 of the BCM and ground.



锟斤拷 If less than specified, repair the signal circuit for a short to ground.



8. If all circuits test normal, replace the BCM.



Component Testing



Ignition Switch



1. Ignition OFF, disconnect the harness connector at the ignition switch.



2. Using the Resistance Test table below, check the resistance between the terminals of the ignition switch listed in each switch position.



If any reading is not as specified, replace the ignition switch.



Repair Instructions



Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the repair.



* Control Module References (See: Testing and Inspection/Programming and Relearning) for BCM replacement, setup, and programming



* Ignition and Start Switch Replacement (See: Powertrain Management/Ignition System/Sensors and Switches - Ignition System/Ignition



Switch/Service and Repair)



B1449



DTC B1449



Diagnostic Instructions



* Perform the Diagnostic System Check - Vehicle (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System



Check - Vehicle) prior to using this diagnostic procedure.



* Review Strategy Based Diagnosis (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Strategy Based Diagnosis) for an



overview of the diagnostic approach.



* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure



Instructions) provides an overview of each diagnostic category.



DTC Descriptors



DTC B1449 03



- Remote Device Voltage Below Threshold

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