P0B09
DTC P0B09
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 Descriptor
DTC P0B09
- Auxiliary Transmission Fluid Pump Supply Voltage Relay Control Circuit
Diagnostic Fault Information
Typical Scan Tool Data
Circuit/System Description
The generator control module also called the starter generator control module is comprised of the following control modules; the hybrid powertrain control module, 14 volt power module and the drive motor control module. These modules are non serviceable and are part of the generator control module.
The transmission fluid pump - auxiliary is used with the transmission fluid pump relay - auxiliary to maintain transmission fluid line pressure to the transmission during Autostop mode. The hybrid powertrain control module monitors the transmission fluid pressure switch to verify that the auxiliary transmission pump is maintaining the proper amount of pressure. The generator control module is comprised of the following control modules; hybrid powertrain control module, 14 volt power module and the motor control module. The transmission fluid pump - auxiliary attaches to the transmission case assembly. The auxiliary transmission fluid pump relay - auxiliary receives voltage through the battery positive voltage circuit. The hybrid powertrain control module controls the auxiliary pump by providing the ground path on the transmission pump relay - auxiliary coil control circuit.
Conditions for Running the DTC
Ignition voltage is greater than 9V.
Conditions for Setting the DTC
The generator control module detects an invalid voltage on the auxiliary transmission fluid pump relay control circuit for greater than 1 second.
Action Taken When the DTC Sets
* DTC P0B09 is a type B DTC.
* Autostop is disabled.
Conditions for Clearing the DTC
DTC P0B09 is a type B DTC.
Reference Information
Schematic Reference
Hybrid Energy Storage Schematics [1][2]Electrical Diagrams
Connector End View Reference
Component Connector End Views Connector End Views By Name
Description and Operation
* Starter Generator Description and Operation Starter Generator Description and Operation
* Generator Control Module Description and Operation Generator Control Module Description and Operation
* Hybrid Modes of Operation Description Hybrid Modes of Operation Description
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
* Electrical Center Identification Views X50A Fuse Block - Underhood - Label
Scan Tool Reference
Control Module References Control Module References for scan tool information
Circuit/System Verification
1. Ignition ON.
2. Verify the Auxiliary Transmission Pump Relay turns on and off/clicks when commanding the Auxiliary Transmission Pump Relay Enable ON and OFF with a scan tool.
• If the Auxiliary Transmission Pump Relay Commanded ON parameter does not change
Refer to Circuit/System Testing.
• If the Auxiliary Transmission Pump Relay Commanded ON parameter changes
All OK.
Circuit/System Testing
1. Ignition OFF, disconnect the KR86 Transmission Fluid Pump Relay - Auxiliary, Ignition ON.
2. Verify a test lamp illuminates between the B+ circuit terminal 30 and ground.
• If the test lamp does not illuminate and the circuit fuse is good
1. Ignition OFF.
2. Test for less than 2 ohm in the B+ circuit end to end.
• If 2 ohm or greater, repair the open/high resistance in the circuit.
• If less than 2 ohm, verify the fuse is not open and there is voltage at the fuse.
• If the test lamp does not illuminate and the circuit fuse is open
1. Ignition OFF.
2. Test for infinite resistance between the B+ circuit and ground.
• If less than infinite resistance, repair the short to ground on the circuit.
• If infinite resistance
3. Test for greater than 10 ohm between the control circuit terminal 87 and ground.
• If less than 10 ohm, repair the short to ground on the circuits or the components listed below:
- Circuit between the KR86 Transmission Fluid Pump Relay - Auxiliary terminal 87 and ground
- Diode circuit between the KR86 Transmission Fluid Pump Relay - Auxiliary terminal 87 and ground
- G5 Transmission Fluid Pump - Auxiliary
• If greater than 10 ohm, test or replace the Transmission Fluid Pump Relay - Auxiliary.
• If the test lamp illuminates
3. Verify a test lamp illuminates between the ignition circuit terminal 86 and ground.
• If the test lamp does not illuminate and the circuit fuse is good
1. Ignition OFF.
2. Test for less than 2 ohm in the ignition circuit end to end.
• If 2 ohm or greater, repair the open/high resistance in the circuit.
• If less than 2 ohm, verify the fuse is not open and there is voltage at the fuse.
• If the test lamp does not illuminate and the circuit fuse is open
1. Ignition OFF.
2. Test for infinite resistance between the ignition circuit and ground.
• If less than infinite resistance, repair the short to ground on the circuit.
• If infinite resistance, test or replace the KR86 Transmission Fluid Pump Relay - Auxiliary.
• If the test lamp illuminates
4. Connect a test lamp between the ignition circuit terminal 86 and the control circuit terminal 85.
5. Verify the test lamp turns ON and OFF when commanding the Auxiliary Transmission Pump Relay Enable ON and OFF with a scan tool.
• If the test lamp is always OFF
1. Ignition OFF, disconnect the harness connector at the K59 starter generator control module, ignition ON.
2. Test for less than 1 V between the control circuit and ground.
• If 1 V or greater, repair the short to voltage on the circuit.
• If less than 1 V
3. Ignition OFF.
4. Test for less than 2 ohm in the control circuit end to end.
• If 2 ohm or greater, repair the open/high resistance in the circuit.
• If less than 2 ohm, replace the K59 starter generator control module.
• If the test lamp is always ON
1. Ignition OFF, disconnect the harness connector at the K59 starter generator control module.
2. Test for infinite resistance between the control circuit and ground.
• If less than infinite resistance, repair the short to ground on the circuit.
• If infinite resistance, replace the K59 starter generator control module.
• If the test lamp turns ON and OFF
6. Verify a test lamp does not illuminate between the control circuit terminal 85 and ground.
• If the test lamp illuminates
Repair the short to voltage on the circuit. If the circuit tests normal replace the K59 starter generator control module.
Component Testing
1. Ignition OFF, disconnect the KR86 Transmission Fluid Pump Relay - Auxiliary.
2. Test for 85-130 ohm between terminals 85 and 86.
• If less than 85 ohm or greater than 130 ohm
Replace the relay.
• If between 85-130 ohm
3. Test for infinite resistance between the terminals listed below:
* 30 and 86
* 30 and 87
* 30 and 85
* 85 and 87
• If less than infinite resistance
Replace the relay.
• If infinite resistance
4. Install a 3 A fused jumper wire between relay terminal 85 and 12 volts. Install a jumper wire between relay terminal 86 and ground.
5. Test for less than 2 ohm between terminals 30 and 87.
• If 2 ohm or greater
Replace the relay.
• If less than 2 ohm
6. All OK.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the repair.
* Control Module References Control Module References for Generator Control Module, also called the Starter Generator Control Module, replacement, programming and setup.
* Relay Replacement (Attached to Wire Harness) Relay Replacement (Attached to Wire Harness)Relay Replacement (Within an Electrical Center) Relay Replacement (Within an Electrical Center) for Transmission Fluid Pump Relay - Auxiliary replacement, Within an Electrical Center