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)
SDGM with HP2
DTC B1380 (SDGM with HP2)
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 B1380 01
- Device Ignition ACCESSORY Circuit Short to Battery
DTC B1380 06
- Device Ignition ACCESSORY Circuit Short to Ground or Open
Diagnostic Fault Information
Circuit/System Description
Modules connected to the high and low speed GMLAN serial data circuits monitor for serial data communications during normal vehicle operation.
Operating information and commands are exchanged among the modules. The modules have prerecorded information about what messages are
needed to be exchanged on the serial data circuits, for each virtual network. The messages are supervised and also, some periodic messages are used
by the receiver module as an availability indication of the transmitter module. Each message contains the identification number of the transmitter
module.
The wake up signal circuit is energized by the body control module (BCM) activate specific modules when the ignition key is in ACC, ON or
START. If the serial data gateway module does not receive this signal when the ignition switch is ON DTC B1380 will set in the SDGM along with
