2010 Cadillac Truck Escalade AWD V8-6.2L Page 478
锟斤拷If the test lamp does not illuminate, test the B+ circuit for an open/high resistance.
Note: The ignition switch component test must be preformed before proceeding with this test to verify the integrity of the switch.
4. Perform the ignition switch component test. The test should pass.
锟斤拷If the ignition switch fails, replace the ignition switch.
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.
