Operation CHARM: Car repair manuals for everyone.

Pinpoint Test O: DTC P0AE1 - Hybrid Battery Precharge Contactor Circuit




High-Voltage Traction Battery

Pinpoint Test O: DTC P0AE1 - Hybrid Battery Precharge Contactor Circuit

Normal Operation

When the ignition is turned on, the Battery Control Module - High Voltage Traction Battery (BCM-HVTB) makes various vehicle checks. If these checks are normal, the BCM-HVTB (Battery Control Module - High Voltage Traction Battery) sends a signal to the contactor to close, which will supply high-voltage power to the vehicle. If a precharge contactor overcurrent condition is sensed by the BCM-HVTB (Battery Control Module - High Voltage Traction Battery), the stop safely hazard (red triangle) warning indicator is illuminated and the vehicle will shut down and/or not start.

This DTC can set as a result of a discharged 12-volt battery, a fault on the DC/DC converter enable circuit, a fault on the high-voltage bus, the Electronically Controlled Continuously Variable Transmission (eCVT) or the high-voltage wiring.

- DTC P0AE1 (Hybrid Battery Precharge Contactor Circuit)- If the precharge contactor attempts to close and current flow exceeds set values, DTC P0AE1 will set. This could indicate a short in the high-voltage system.

This pinpoint test is intended to diagnose the following:

- High-voltage cable assembly

- BCM-HVTB (Battery Control Module - High Voltage Traction Battery)

- High Voltage Traction Battery (HVTB)

- eCVT (Electronically Controlled Continuously Variable Transmission)

PINPOINT TEST O : DTC P0AE1 - HYBRID BATTERY PRECHARGE CONTACTOR CIRCUIT

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 Flex Probe Kit for all test connections to prevent damage to the wiring terminals. Do not use standard multi-meter probes.

O1 CHECK FOR PCM AND TCM (Transmission Control Module) DTCs

- Connect the scan tool.

- Ignition ON.

- Enter the following diagnostic mode on the scan tool: Self Test- PCM.

- Enter the following diagnostic mode on the scan tool: Self Test- Transmission Control Module (TCM).

Is DTC P0A10 or P0A11 present in the PCM or is DTC P0A78 or P0A7A present in the TCM (Transmission Control Module) ?

Yes
REFER to Computers and Control Systems Information to diagnose those DTCs first.

No
GO to O2.

O2 CHECK THE 12-VOLT BATTERY CONDITION

- and carry out Pinpoint Test A: Battery Condition Test to determine if the battery can hold a charge and is OK for use Pinpoint Tests.

Does the 12-volt battery pass the condition test?

Yes
GO to O3.

No
INSTALL a new battery. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

O3 CHECK HIGH-VOLTAGE CABLE CONTINUITY BETWEEN THE TRACTION BATTERY AND THE TRANSMISSION

- Ignition OFF.

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

- Disconnect: Traction Battery Control Module (TBCM) C4227C.

- Disconnect: TCM (Transmission Control Module) C1458D.

- Measure the resistance between TBCM (Traction Battery Control Module) C4227C-(+), circuit HYT03 (OG), harness side, and TCM (Transmission Control Module) C1458D-(+), circuit HYT03 (OG), harness side, and between TBCM (Traction Battery Control Module) C4227C-(-), circuit HYT04 (OG), harness side, and TCM (Transmission Control Module) C1458D-(-), circuit HYT04 (OG), harness side.





Are the resistances less than 5 ohms?

Yes
GO to O4.

No
INSTALL a new HVTB (High Voltage Traction Battery) -to-eCVT (Electronically Controlled Continuously Variable Transmission) high-voltage cable. REFER to High-Voltage Cables . CLEAR the DTCs. REPEAT the self-test.

O4 CHECK FOR A SHORT TO GROUND IN THE TRANSMISSION

NOTE: Due to circuit components internal to the eCVT (Electronically Controlled Continuously Variable Transmission), the resistance reading may fluctuate and/or take several seconds before an actual measurement can be made.

- Disconnect: Transaxle Control Module C1458E.

- Measure the resistance between TCM (Transmission Control Module) C1458E pin-(+), circuit HYT03 (OG), component side and ground, and between TCM (Transmission Control Module) C1458E pin-(-), circuit HYT04 (OG), component side and ground





Is the resistance greater than 50 ohms?

Yes
GO to O5.

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

O5 CHECK FOR A SHORT TOGETHER IN THE TRANSMISSION

NOTE: Due to circuit components internal to the eCVT (Electronically Controlled Continuously Variable Transmission), the resistance reading may fluctuate and/or take several seconds before an actual measurement can be made.

- Measure the resistance between TCM (Transmission Control Module) C1458E pin-(+), circuit HYT03 (OG), component side, and TCM (Transmission Control Module) C1458E pin-(-), circuit HYT04 (OG), component side.





Is the resistance greater than 50 ohms?

Yes
GO to O6.

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

O6 CHECK FOR A SHORT IN THE DC/DC CONVERTER OR WIRING

- Measure the resistance between TCM (Transmission Control Module) C1458E-(+), circuit HYT03 (OG), harness side, and TCM (Transmission Control Module) C1458E-(-), circuit HYT04 (OG), harness side.





- Measure the resistance between TCM (Transmission Control Module) C1458E-(+), circuit HYT03 (OG), harness side and ground, and between TCM (Transmission Control Module) C1458E-(-), circuit HYT04 (OG), harness side and ground.





Is the resistance greater than 10,000 ohms?

Yes
GO to O8.

No
GO to O7.

O7 CHECK FOR A SHORT IN THE DC/DC CONVERTER WIRING HARNESS

- Disconnect: DC/DC Converter C1457D.

- Measure the resistance between TCM (Transmission Control Module) C1458E-(+), circuit HYT03 (OG), harness side, and TCM (Transmission Control Module) C1458E-(-), circuit HYT04 (OG), harness side.





- Measure the resistance between TCM (Transmission Control Module) C1458E-(+), circuit HYT03 (OG), harness side and ground, and between TCM (Transmission Control Module) C1458E-(-), circuit HYT04 (OG), harness side and ground.





Is the resistance greater than 10,000 ohms?

Yes
INSTALL a new DC/DC converter. CLEAR the DTCs. REPEAT the self-test.

No
INSTALL a new DC/DC converter wiring harness. CLEAR the DTCs. REPEAT the self-test.

O8 CHECK FOR VOLTAGE AT THE TBCM (Traction Battery Control Module)

- Disconnect: TBCM (Traction Battery Control Module) C4227A.

- Ignition ON.

- Measure the voltage between each of the following pins and ground:
- C4227A-4, circuit SBB15 (WH/RD), harness side
- C4227A-5, circuit SBB15 (WH/RD), harness side
- C4227A-6, circuit SBB15 (WH/RD), harness side
- C4227A-10, circuit SBB05 (GY/RD), harness side
- C4227A-11, circuit SBB05 (GY/RD), harness side
- C4227A-19, circuit CBB23 (BN/YE), harness side






Is the voltage greater than 10 volts?

Yes
GO to O9.

No
If voltage is not present on pin 4, 5 or 6, VERIFY Battery Junction Box (BJB) fuse 15 (50A) is OK. If the fuse is OK, REPAIR circuit SBB15 (WH/RD).

If voltage is not present on pin 10 or 11, VERIFY BJB (Battery Junction Box) fuse 5 (10A) is OK. If the fuse is OK, REPAIR circuit SBB05 (GY/RD).

If voltage is not present on pin 19, VERIFY BJB (Battery Junction Box) fuse 23 (5A) is OK. If the fuse is OK, REPAIR circuit CBB23 (BN/YE).

If any fuse is not OK, REFER to the Wiring Diagrams to identify the possible causes of the circuit short Electrical Diagrams.

CLEAR the DTCs. REPEAT the self-test.

O9 CHECK FOR CORRECT HVTB (High Voltage Traction Battery) OPERATION

- Ignition OFF.

- Check TBCM (Traction Battery Control Module) C4227A, TCM (Transmission Control Module) C1458E, DC/DC converter C1457D, TBCM (Traction Battery Control Module) C4227C, and TCM (Transmission Control Module) C1458D for:
- corrosion.

- pushed-out pins.

- spread terminals.


- Connect: TBCM (Traction Battery Control Module) C4227A.

- Connect: TBCM (Traction Battery Control Module) C4227C.

- Connect: TCM (Transmission Control Module) C1458D.

- Connect: TCM (Transmission Control Module) C1458E.

- Connect: DC/DC converter C1457D.

- Make sure the connectors seat correctly before operating the system.

- Connect the scan tool.

- Ignition ON.

- Enter the following diagnostic mode on the scan tool: Self Test- BCM-HVTB (Battery Control Module - High Voltage Traction Battery).

Is DTC P0AE1 present?

Yes
INSTALL a new HVTB (High Voltage Traction Battery). REFER to High-Voltage Traction Battery . CLEAR the DTCs. REPEAT the self-test.

No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the self-test.