DTC C0847, C0848, C1240 or C1241
Diagnostic Instructions
DTC Descriptors
DTC C0847 00: Device Ignition 1 Circuit Low
DTC C0848 00: Device Ignition 1 Circuit High
DTC C1240 00: Electronic Brake Control Module Ignition On/Start Switch Circuit Low Voltage
DTC C1241 00: Electronic Brake Control Module Ignition On/Start Switch Circuit High Voltage
Diagnostic Fault Information
Circuit
| Short to Ground
| Open/High Resistance
| Short to Voltage
| Signal Performance
|
Ignition
| C0847 00, C1240 00
| C0847 00, C1240 00
| C0848 00, C1241 00
| --
|
Circuit/System Description
The body control module (BCM) controls the ignition relay through the control circuit by applying voltage to the circuit. The ignition circuit is energised when the vehicle power mode is Vehicle ON or Vehicle in Service Mode. The hybrid powertrain control module 2 sends the Vehicle ON or Vehicle in Service Mode power mode status in a serial data message to the electronic brake control module.
Conditions for Running the DTC
C0847 00, C1240 00
| • | Hybrid powertrain control module 2 is awake. |
| • | System voltage between 9 and 16 V. |
| • | Vehicle power mode is Vehicle ON or Vehicle in Service Mode. |
| • | The DTC can only run when the output is activated. |
C0848 00, C1241 00
| • | Hybrid powertrain control module 2 is awake. |
| • | System voltage between 9 and 16 V. |
| • | Vehicle power mode is Vehicle OFF. |
Conditions for Setting the DTC
C0847 00, C1240 00
| • | Hybrid powertrain control module 2 is awake. |
| • | Ignition output is active and a short-circuit to earth or open-circuit is detected for greater than 5 seconds. |
C0848 00, C1241 00
| • | Hybrid powertrain control module 2 is awake. |
| • | Ignition output is not active and a short-circuit to battery is detected for greater than 5 seconds. |
Action Taken When the DTC Sets
No action is taken.
Conditions for Clearing the DTC
| • | The current DTC will clear when the malfunction is no longer present during a DTC check. |
| • | A history DTC clears when the module power mode cycle counter reaches the reset threshold of 40, without a repeat of the malfunction. |
Diagnostic Aids
A short-circuit to voltage in the ignition circuit will keep the vehicle modules awake, which can drain the vehicle's battery.
Reference Information
Schematic Reference
Power Distribution Schematics
Connector End View Reference
Component Connector End Views
Description and Operation
Power Mode Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Verification
Verify DTC B144B is not set.
Circuit/System Testing
- Disconnect the harness connector at the K17 electronic brake control module.
- Vehicle OFF, verify that a test lamp does not illuminate between the ignition circuit terminal 14 and earth.
| ⇒ | If the test lamp illuminates, test the ignition circuit for a short to voltage. If the circuit tests normal, refer to Power Mode Mismatch . |
- Vehicle in Service Mode, verify that a test lamp illuminates between the ignition circuit terminal 14 and earth.
| ⇒ | If the test lamp does not illuminate, test the ignition circuit for a short to ground or an open/high resistance. If the circuit tests normal, refer to Power Mode Mismatch . |
- If all circuits test normal, replace the K17 electronic brake control module.
Repair Instructions
Perform the Diagnostic Repair Verification after completing the repair.
See Control Module References for electronic brake control module replacement, programming and set-up
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