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Pinpoint Test A: DTC P0A0A:00




High-Voltage Traction Battery

Pinpoint Test A: DTC P0A0A:00

Refer to Wiring Diagram Set 12, Charging System for schematic and connector information. [1][2]Diagrams By Number

Normal Operation

The Battery Energy Control Module (BECM) checks for continuity of the high-voltage system interlock circuit. The interlock circuit must have continuity before high-voltage will be supplied to the vehicle. The interlock circuit voltage travels through each of the high-voltage components and high-voltage cables and back to the BECM (Battery Energy Control Module). This fault will illuminate the stop safely hazard (red triangle) warning indicator and shut down the vehicle.

- DTC P0A0A:00 (High Voltage System Interlock Circuit: No Sub Type Information)- Fault sets when the BECM (Battery Energy Control Module) does not sense interlock circuit continuity. This indicates the interlock circuit is open.

This pinpoint test is intended to diagnose the following:

- Air Conditioning Compressor Module (ACCM)

- BECM (Battery Energy Control Module)

- DC to DC Converter Control Module (DC/DC)

- Transmission Control Module (TCM) (part of Electronically Controlled Continuously Variable Transmission (eCVT))

- High-voltage cables

PINPOINT TEST A : DTC P0A0A:00

WARNING: To prevent the risk of high-voltage shock, always follow precisely all warnings and service instructions, including instructions to depower the system. The high-voltage hybrid system utilizes approximately 300 volts DC, provided through high-voltage cables to its components and modules. The high-voltage cables and wiring are identified by orange harness tape or orange wire covering. All high-voltage components are marked with high-voltage warning labels with a high-voltage symbol. Failure to follow these instructions may result in serious personal injury or death.

NOTICE: Use the correct probe adapter(s) from the Flex Probe Kit when taking measurements. Failure to use the correct probe adapter(s) may damage the connector.

A1 CHECK BECM (Battery Energy Control Module) PID HIGH VOLTAGE INTERLOCK INPUT STATUS (VOLTINTINP)

- Ignition ON.

- Connect the scan tool.

- Enter the following diagnostic mode on the scan tool: DataLogger- BECM (Battery Energy Control Module).

- Monitor the BECM (Battery Energy Control Module) PID VOLTINTINP.

Does the PID VOLTINTINP read closed?

Yes
Concern is not present at this time and may be intermittent. INSPECT all high-voltage connections. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

No
GO to A2.

A2 MEASURE RESISTANCE OF INTERLOCK CIRCUIT

- Ignition OFF.

- Disconnect: BECM (Battery Energy Control Module) C4237B.

- Measure the resistance between BECM (Battery Energy Control Module) C4237B-44, circuit J1-A44 harness side and BECM (Battery Energy Control Module) C4237B-47, circuit J1-A47 harness side.





- Repeat the measurement between BECM (Battery Energy Control Module) C4237B-44, circuit J1-A44 harness side and BECM (Battery Energy Control Module) C4237B-47, circuit J1-A47 harness side while wiggling the connectors and flexing the wire harness, where accessible.

Are the resistances less than 5 ohms?

Yes
INSTALL a new BECM (Battery Energy Control Module). REFER to Battery Energy Control Module (BECM) . CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

No
GO to A3.

A3 CHECK INTERLOCK CIRCUIT TO TCM (Transmission Control Module)

WARNING: Never install the service disconnect plug with the high-voltage bussed electrical center (BEC) cover removed. Always install the cover prior to connecting the service disconnect plug. The high-voltage BEC cover prevents inadvertent contact with the high voltage which is present at several points under the cover. Failure to follow these instructions may result in serious personal injury or death.

- Ignition OFF.

- Depower the High Voltage Traction Battery (HVTB) system. Refer to High-Voltage Traction Battery Systems Depowering .

- Disconnect the 12-volt battery.

- Disconnect: High-voltage Bussed Electrical Center (BEC) C4236B.

- Disconnect: TCM (Transmission Control Module) C1458C.

- Measure the resistance between high-voltage BEC (Bussed Electrical Center) C4236B, harness side and TCM (Transmission Control Module) C1458C, harness side as follows:

BEC (Bussed Electrical Center) C4236B Circuit TCM (Transmission Control Module) C1458C C4236B-1 CYB04 (VT/BN) C1458C-1 C4236B-2 CYB03 (BN/YE) C1458C-2





- Repeat the measurement between BEC (Bussed Electrical Center) C4236B, harness side and TCM (Transmission Control Module) C1458C, harness side while wiggling the connectors and flexing the wire harness, where accessible.

Are the resistances less than 5 ohms?

Yes
GO to A4.

No
INSTALL new high-voltage cables. REFER to High-Voltage Cables . CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

A4 CHECK INTERLOCK CIRCUIT TO ACCM (Air Conditioning Compressor Module) AND DC/DC (DC to DC Converter Control Module)

- Disconnect: BEC (Bussed Electrical Center) C4236A.

- Disconnect: ACCM (Air Conditioning Compressor Module) C1469B.

- Disconnect: DC/DC (DC to DC Converter Control Module) C1457A.

- Measure the resistance between high-voltage BEC (Bussed Electrical Center) C4236A, harness side, ACCM (Air Conditioning Compressor Module) C1469B, harness side and DC/DC (DC to DC Converter Control Module) C1457A, harness side as follows:

BEC (Bussed Electrical Center) C4236A Circuit DC/DC (DC to DC Converter Control Module) C1457A C4236A-3 CYD02 (WH/BN) C1457A-3

BEC (Bussed Electrical Center) C4236A Circuit ACCM (Air Conditioning Compressor Module) C1469B C4236A-4 CYB03 (BN/YE) C1469B-4

ACCM (Air Conditioning Compressor Module) C1469B Circuit DC/DC (DC to DC Converter Control Module) C1457A C1469B-3 CYD01 (BN/WH) C1457A-4






- Repeat the measurements between BEC (Bussed Electrical Center) C4236A, harness side, ACCM (Air Conditioning Compressor Module) C1469B, and DC/DC (DC to DC Converter Control Module) C1457A, harness side while wiggling the connectors and flexing the wire harness, where accessible.

Are the resistances less than 5 ohms?

Yes
GO to A5.

No
INSTALL new high-voltage cables. REFER to High-Voltage Cables . CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

A5 CHECK DC/DC (DC to DC Converter Control Module) INTERLOCK RESISTANCE

- Measure the resistance between DC/DC (DC to DC Converter Control Module) C1457A pin 3 and pin 4, component side.





Is the resistance less than 5 ohms?

Yes
GO to A6.

No
INSTALL a new DC/DC (DC to DC Converter Control Module). CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

A6 CHECK ACCM (Air Conditioning Compressor Module) INTERLOCK RESISTANCE

- Measure the resistance between ACCM (Air Conditioning Compressor Module) C1469B, pin 3 and pin 4, component side.





Is the resistance less than 5 ohms?

Yes
GO to A7.

No
INSTALL a new ACCM (Air Conditioning Compressor Module) and A/C compressor assembly. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

A7 CHECK TCM (Transmission Control Module) INTERLOCK RESISTANCE

- Measure the resistance between TCM (Transmission Control Module) C1458C, pin 1 and pin 2, component side.





Is the resistance less than 5 ohms?

Yes
GO to A8.

No
INSTALL a eCVT (Electronically Controlled Continuously Variable Transmission). CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

A8 CHECK THE HIGH-VOLTAGE CABLES USING BECM (Battery Energy Control Module) PID HIGH VOLTAGE INTERLOCK INPUT STATUS (VOLTINTINP)

- Install new high-voltage cables. Refer to High-Voltage Cables .

- Connect the 12-volt battery.

- Connect: Service Disconnect Plug.

- Ignition ON.

- Enter the following diagnostic mode on the scan tool: DataLogger- BECM (Battery Energy Control Module).

- Monitor the BECM (Battery Energy Control Module) PID VOLTINTINP.

Does the PID VOLTINTINP read closed?

Yes
Repair is complete. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

No
GO to A9.

A9 CHECK THE DC/DC (DC to DC Converter Control Module) USING BECM (Battery Energy Control Module) PID HIGH VOLTAGE INTERLOCK INPUT STATUS (VOLTINTINP)

WARNING: Never install the service disconnect plug with the high-voltage bussed electrical center (BEC) cover removed. Always install the cover prior to connecting the service disconnect plug. The high-voltage BEC cover prevents inadvertent contact with the high voltage which is present at several points under the cover. Failure to follow these instructions may result in serious personal injury or death.

- Ignition OFF.

- Depower the HVTB (High Voltage Traction Battery) system. Refer to High-Voltage Traction Battery Systems Depowering .

- Disconnect the 12-volt battery.

- Install a new DC/DC (DC to DC Converter Control Module).

- Connect the 12-volt battery.

- Connect: Service Disconnect Plug.

- Ignition ON.

- Enter the following diagnostic mode on the scan tool: DataLogger- BECM (Battery Energy Control Module).

- Monitor the BECM (Battery Energy Control Module) PID VOLTINTINP.

Does the PID VOLTINTINP read closed?

Yes
Repair is complete. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

No
GO to A10.

A10 CHECK THE ACCM (Air Conditioning Compressor Module) USING BECM (Battery Energy Control Module) PID HIGH VOLTAGE INTERLOCK INPUT STATUS (VOLTINTINP)

WARNING: Never install the service disconnect plug with the high-voltage bussed electrical center (BEC) cover removed. Always install the cover prior to connecting the service disconnect plug. The high-voltage BEC cover prevents inadvertent contact with the high voltage which is present at several points under the cover. Failure to follow these instructions may result in serious personal injury or death.

- Ignition OFF.

- Depower the HVTB (High Voltage Traction Battery) system. Refer to High-Voltage Traction Battery Systems Depowering .

- Disconnect the 12-volt battery.

- Install a new ACCM (Air Conditioning Compressor Module).

- Connect the 12-volt battery.

- Connect: Service Disconnect Plug.

- Ignition ON.

- Enter the following diagnostic mode on the scan tool: DataLogger- BECM (Battery Energy Control Module).

- Monitor the BECM (Battery Energy Control Module) PID VOLTINTINP.

Does the PID VOLTINTINP read closed?

Yes
Repair is complete. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

No
GO to A11.

A11 CHECK THE HVTB (High Voltage Traction Battery) USING BECM (Battery Energy Control Module) PID HIGH VOLTAGE INTERLOCK INPUT STATUS (VOLTINTINP)

WARNING: Never install the service disconnect plug with the high-voltage bussed electrical center (BEC) cover removed. Always install the cover prior to connecting the service disconnect plug. The high-voltage BEC cover prevents inadvertent contact with the high voltage which is present at several points under the cover. Failure to follow these instructions may result in serious personal injury or death.

- Ignition OFF.

- Depower the HVTB (High Voltage Traction Battery) system. Refer to High-Voltage Traction Battery Systems Depowering .

- Disconnect the 12-volt battery.

- Install a new HVTB (High Voltage Traction Battery) (includes HVTB (High Voltage Traction Battery) system wire harness). Refer to High-Voltage Traction Battery .

- Connect the 12-volt battery.

- Connect: Service Disconnect Plug.

- Ignition ON.

- Enter the following diagnostic mode on the scan tool: DataLogger- BECM (Battery Energy Control Module).

- Monitor the BECM (Battery Energy Control Module) PID VOLTINTINP.

Does the PID VOLTINTINP read closed?

Yes
Repair is complete. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

No
INSTALL a new eCVT (Electronically Controlled Continuously Variable Transmission). CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
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