B137A
DTC B137A
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions Diagnostic Procedure Instructions provides an overview of each diagnostic category.
DTC Descriptors
DTC B137A 01
-
Hybrid Accessory Wake Up Circuit - Short to Battery
DTC B137A 06
-
Hybrid Accessory Wake Up 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 serial data gateway (SDG) module to activate the drive motor generator power inverter module (PIM) and the drive motor generator battery control module. If the wake up signal is not responded to by all three modules, this DTC sets in the SDG module.
Conditions for Running the DTC
* The system voltage is between 9-16 volts.
* The vehicle power mode master requires serial data communication to occur.
Conditions for Setting the DTC
A short circuit exists on the wake up signal circuit of the SDG module.
Action Taken When the DTC Sets
The malfunction indicator lamp (MIL) illuminates and the driver information center (DIC) displays the message Service Hybrid System.
Conditions for Clearing the DTC
* A current DTC clears when the malfunction is no longer present.
* A history DTC clears when the module ignition cycle counter reaches the reset threshold of 50, without a repeat of the malfunction.
Reference Information
Schematic Reference
* Data Communication Schematics Electrical Diagrams
* Hybrid Controls Schematics
Connector End View Reference
Component Connector End Views 1-2 Shift Solenoid (SS) Valve (M30)
Description and Operation
Data Link Communications Description and Operation Description and Operation
Electrical Information Reference
* Circuit Testing Circuit Testing
* Connector Repairs Connector Repairs
* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections
* Wiring Repairs Wiring Repairs
Scan Tool Reference
Control Module References Control Module References for scan tool information
Special Tools
* EL-48569 Terminal Covers
* EL-48900 HEV Safety Kit
Circuit/System Testing
Danger:
Always perform the High Voltage Disabling procedure prior to servicing any High Voltage component or connection. Personal Protection Equipment (PPE) and proper procedures must be followed.
The High Voltage Disabling procedure will perform the following tasks:
* Identify how to disable high voltage.
* Identify how to test for the presence of high voltage.
* Identify condition under which high voltage is always present and personal protection equipment (PPE) and proper procedures must be followed.
Failure to follow the procedures exactly as written may result in serious injury or death.
1. Perform the High Voltage Disabling procedure.
2. Reconnect the 12-volt battery.
3. Ignition OFF, disconnect harness connector X1 of the drive motor generator battery control module and the PIM.
4. Ignition ON, verify that a test lamp illuminates between the wake up signal circuit of the PIM and ground, and the drive motor generator battery control module and ground as follows:
* PIM X1 19
* BECM X1 12
• If the test lamp does not illuminate, test the circuit for a short to ground or open/high resistance. If the circuit tests normal, replace the SDG module.
5. Ignition OFF, verify that a test lamp does not illuminate between the PIM wake up signal circuit terminal 19 and ground.
• If the test lamp illuminates, test the circuit for a short to voltage. If the circuit tests normal, replace the SDG module.
6. If all circuits test normal, replace the SDG module.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the diagnostic procedure.
Control Module References Control Module References for module replacement, setup, and programming