High Voltage Traction Battery: Overview Ford Escape II

Principles of Operation

The high-voltage system has a floating ground. When the engine is operating or the vehicle is moving, the high-voltage generator generates high-voltage AC electricity. High-voltage AC electricity can be consumed or generated by the motor generator, the traction motor or a combination of both motors. Excess high-voltage current is converted from high-voltage AC to high-voltage DC electrical power inside the motor generator unit and transmitted through the high-voltage cables. The high-voltage DC electrical power is converted to low-voltage DC electrical power through the DC/DC converter. This low-voltage DC electrical power is then supplied to the 12-volt battery through the low-voltage battery cables.

Normal Operation

With the ignition switch in the ON position and the engine running, the High Voltage Traction Battery (HVTB) has 2 internal cooling fans that circulate air through the HVTB.

This pinpoint test is intended to diagnose the following

1. HVTB internal cooling fans (part of the HVTB)
2. HVTB
3. Climate control system air leakage due to poor sealing

1. A1 CHECK THE INTERNAL FANS WARNING: Wear high-voltage insulated safety gloves and a face shield when working with high-voltage batteries or cables. The high-voltage insulated safety gloves should be of the appropriate safety and protection rating. Inspect the gloves before use and always wear them with the leather outer glove. Any hole in the rubber insulating glove is a potential entry point for high-voltage. Failure to follow these instructions may result in serious personal injury or death. WARNING: Turn OFF the ignition switch for a minimum of 5 minutes before removing high-voltage cables. High-voltage cables and wiring are orange in color. The nominal high-voltage traction battery voltage (HVTB) is 330 V DC. Failure to follow these instructions may result in serious personal injury or death. WARNING: Depower the high-voltage traction battery (HVTB) before carrying out any removal or installation procedures affecting the high-voltage battery system. Failure to follow this instruction may result in serious personal injury or death. WARNING: When servicing the high-voltage system, establish a buffer zone per the specified procedure. Failure to follow this instruction may result in serious personal injury or death. Start the engine. NOTE: The engine must have started at least once for the cooling fans to have cycled on. NOTE: Verify the HVTB rear lift eye cap plug is correctly positioned and not damaged. NOTE: Verify the A/C return duct between the HVTB and the climate control system is correctly positioned and not damaged. NOTE: The cooling fans may run at various speeds due to varying vehicle and HVTB conditions. The fan speed increases with increased temperature and may run at 40% to 100% duty cycle. A fan running at 40% duty cycle is much quieter than the same fan running at 100% duty cycle. During the on-demand self test, the fans run at 100% duty cycle. With the ignition switch in the ON position and the engine ON or OFF, use a stethoscope or equivalent listening device to probe the HVTB area for unusual or excessive noise. Compare the noise to a similar vehicle. Is the noise coming from the HVTB internal cooling fans? Yes: INSTALL a new HVTB. REFER to «HIGH-VOLTAGE TRACTION BATTERY»(ref-344108-S23562780222009101600000) . TEST the system for normal operation. No: REFER to «NOISE, VIBRATION & HARSHNESS»(ref-344053) to continue diagnosis.

With the engine running and the audio unit ON (the audio unit MUST be OEM), there should be minimal interference audible from the speakers (compare to a similar vehicle).

This pinpoint test is intended to diagnose the following

1. Audio unit
2. Generator (part of the Electronically Controlled Continuously Variable Transmission (eCVT)])
3. DC/DC converter

With the ignition switch in the ON position and the engine ON or OFF, the vehicle climate control system maintains the High Voltage Traction Battery (HVTB) temperature in a specific range. The HVTB has 2 internal fans that circulate climate controlled air within the HVTB so a specific temperature range is maintained. A battery compartment thermistor is hardwired to the HVTB for the battery compartment temperature input. The HVTB also monitors the battery compartment blend door actuator in order to determine the direction the HVTB operates the battery blend door motor. The battery blend door controls whether the air flowing into the battery compartment is fresh air or recirculated air. A battery thermal expansion solenoid valve also controls the refrigerant pressure, thereby controlling the incoming air temperature. The ideal HVTB temperature is 25°C (77°F) with a desired range of 20°C (68°F) to 30°C (86°F).

1. DTC P0A7E Hybrid Battery Pack Over Temperature - The HVTB temperature window is -40°C (-104°F) to 55°C (131°F). If the HVTB temperature exceeds 55°C (131°F) and the vehicle is driven aggressively, the Battery Control Module (BCM) may set this DTC and if the HVTB temperature exceeds 57°C (135°F), the BCM may shut the vehicle down.

This pinpoint test is intended to diagnose the following

1. Vehicle climate control system
2. HVTB internal fans
3. HVTB

With the ignition switch in the ON position and the engine ON or OFF (the engine must have started at least once after the key was cycled to ON), 2 internal fans in the High Voltage Traction Battery (HVTB) circulate air to maintain a specific temperature range. A failure of the cooling fan(s) or their associated circuits causes one (or both) of the DTCs to be set.

1. P0A81 Hybrid Battery Pack Cooling Fan 1 Control Circuit - An open in Battery Junction Box (BJB) fuse 15 (50A), an HVTB cooling fan 1 fault or circuit SBB15 (WH/RD) feedback status does not match Battery Control Module (BCM) commands or an open or high resistance on HVTB ground circuit GD149 (BK/GY) causes the BCM to set this DTC.
2. P0A96 Hybrid Battery Pack Cooling Fan 2 Control Circuit - An open in BJB fuse 15 (50A), an HVTB cooling fan 2 fault or circuit SBB15 (WH/RD) feedback status does not match BCM commands or an open or high resistance on HVTB ground circuit GD149 (BK/GY) causes the BCM to set this DTC.

This pinpoint test is intended to diagnose the following

1. Fuse
2. Circuitry
3. Cooling fan 1 or 2 (part of HVTB)
4. HVTB

Scheme 576

Scheme 577

1. D1 VERIFY THE HVTB INTERNAL FANS ARE OPERATIONAL WARNING: Wear high-voltage insulated safety gloves and a face shield when working with high-voltage batteries or cables. The high-voltage insulated safety gloves should be of the appropriate safety and protection rating. Inspect the gloves before use and always wear them with the leather outer glove. Any hole in the rubber insulating glove is a potential entry point for high-voltage. Failure to follow these instructions may result in serious personal injury or death. WARNING: Turn OFF the ignition switch for a minimum of 5 minutes before removing high-voltage cables. High-voltage cables and wiring are orange in color. The nominal high-voltage traction battery voltage (HVTB) is 330 V DC. Failure to follow these instructions may result in serious personal injury or death. WARNING: Depower the high-voltage traction battery (HVTB) before carrying out any removal or installation procedures affecting the high-voltage battery system. Failure to follow this instruction may result in serious personal injury or death. WARNING: When servicing the high-voltage system, establish a buffer zone per the specified procedure. Failure to follow this instruction may result in serious personal injury or death. Enter the following diagnostic mode on the scan tool: BCM Self Test/Retrieve and Record On-Demand and Continuous Memory DTCs. NOTE: Use a stethoscope or equivalent listening device to probe the HVTB area. NOTE: The cooling fans may cycle on or off with the key ON, engine ON or OFF. With the ignition switch in the ON position and the engine ON or OFF (the engine must have run at least once after the key was cycled to ON), verify the HVTB internal fans are operating correctly. Are the HVTB internal fans operating correctly? Yes: INSTALL a new HVTB. REFER to «HIGH-VOLTAGE TRACTION BATTERY»(ref-344108-S23562780222009101600000) . TEST the system for normal operation. No: TURN the ignition OFF, then GO to D2 .
2. D2 CHECK CIRCUIT SBB15 (WH/RD) FOR VOLTAGE Ignition OFF. Disconnect: BCM C4 27a. Measure the voltage between BCM C4227a pins, harness side and ground as follows: VOLTAGE REFERENCE Pin Circuit 4 SBB15 (WH/RD) 5 SBB15 (WH/RD) 6 SBB15 (WH/RD) Is the voltage greater than 10 volts? Yes: GO to D3 . No: VERIFY that the BJB fuse 15 (50A) is OK; if OK, REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
3. D3 CHECK CIRCUIT GD149 (BK/GY) FOR AN OPEN Measure the resistance between BCM C 27a pins, harness side and ground as follows: RESISTANCE REFERENCE Pin Circuit 35 GD149 (BK/GY) 36 GD149 (BK/GY) 37 GD149 (BK/GY) Is the resistance less than 5 ohms? Yes: GO to D4 . No: REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
4. D4 CHECK FOR CORRECT BCM OPERATION NOTE: This pinpoint test step only addresses the 6-pin and 40-pin connectors for the BCM. It is not necessary to disconnect the high-voltage connectors when following this pinpoint test step procedure. Disconnect BCM electrical connector C4227a. Check for: corrosion. pushed-out pins. Connect BCM electrical connector C 27a and make sure it seats correctly. Operate the system and verify the concern is still present. Is the concern still present? Yes: INSTALL a new HVTB. REFER to «HIGH-VOLTAGE TRACTION BATTERY»(ref-344108-S23562780222009101600000) . TEST the system for normal operation. 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.

With the ignition switch in the ON position and the engine ON or OFF (the engine must have started at least once after the key was cycled to ON), the planetary gear set in the Electronically Controlled Continuously Variable Transmission (eCVT) engages the generator (also in the eCVT), which charges the High Voltage Traction Battery (HVTB) and supplies high-voltage to the DC/DC converter. The DC/DC converter steps the high voltage down to 12 volts (operating range of 13.35-16 volts). The DC/DC converter charges the low-voltage battery which is used to power the PCM and low voltage components.

1. DTC P0A8B 14-Volt Power Module System Voltage - Voltage less than 2.5 volts or greater than 25 volts on input circuit SBB05 (GY/RD) indicates an internal Battery Control Module (BCM) fault, or if the 12-volt battery has recently had the terminals disconnected/cleaned or if a new 12-volt battery has been recently installed may cause the BCM to set this DTC.
2. DTC P0A8D 14-Volt Power Module System Voltage Low - Voltage less than 10 volts on input circuit SBB05 (GY/RD) for 5 seconds continuously, or if the 12-volt battery has recently had the terminals disconnected/cleaned or if a new 12-volt battery has been recently installed may cause the BCM to set this DTC.
3. DTC P0A8E 14-Volt Power Module System Voltage High - Voltage greater than 16 volts on input circuit SBB05 (GY/RD) for 5 seconds continuously, or if the 12-volt battery has recently had the terminals disconnected/cleaned or if any external jump start procedure has been carried out recently may cause the BCM to set this DTC.

This pinpoint test is intended to diagnose the following

1. 12-volt battery
2. HVTB

Scheme 578

1. E1 CHECK THE HISTORY OF THE VEHICLE WARNING: Wear high-voltage insulated safety gloves and a face shield when working with high-voltage batteries or cables. The high-voltage insulated safety gloves should be of the appropriate safety and protection rating. Inspect the gloves before use and always wear them with the leather outer glove. Any hole in the rubber insulating glove is a potential entry point for high-voltage. Failure to follow these instructions may result in serious personal injury or death. WARNING: Turn OFF the ignition switch for a minimum of 5 minutes before removing high-voltage cables. High-voltage cables and wiring are orange in color. The nominal high-voltage traction battery voltage (HVTB) is 330 V DC. Failure to follow these instructions may result in serious personal injury or death. WARNING: Depower the high-voltage traction battery (HVTB) before carrying out any removal or installation procedures affecting the high-voltage battery system. Failure to follow this instruction may result in serious personal injury or death. WARNING: When servicing the high-voltage system, establish a buffer zone per the specified procedure. Failure to follow this instruction may result in serious personal injury or death. Verify if the low-voltage battery has recently had the terminals disconnected/cleaned or if a new low-voltage battery has been recently installed. If so, DTCs P0A8B, P0A8D and P0A8E may have been set. Has the low-voltage battery recently had the terminals disconnected/cleaned or has a new low-voltage battery recently been installed? Yes: CLEAR the DTCs. REPEAT the self-test. If the self-test passes, RETURN the vehicle to the customer until the concern can be verified. No: GO to E2 .
2. E2 VERIFY THE INTEGRITY OF THE LOW-VOLTAGE BATTERY Carry out the 12-Volt Battery Condition Test to determine if the battery can hold a charge and is OK for use. Refer to «BATTERY, MOUNTING AND CABLES»(ref-344091) . Does the battery pass the condition test? Yes: GO to E3 . No: INSTALL a new 12-volt battery. REFER to «12 VOLT BATTERY»(ref-344108-S16855202342009101600000) . TEST the system for normal operation.
3. E3 CHECK THE BCM DTCs Enter the following diagnostic mode on the scan tool: BCM Self Test/Retrieve and Record On-Demand and Continuous Memory DTCs. Are the following DTCs retrieved: P0A8B, P0A8D or P0A8E? Yes: GO to E4 . No: REFER to the «INTRODUCTION - GASOLINE MODELS»(ref-342225) to continue diagnosis.
4. E4 CHECK FOR 12-VOLT INPUT ON CIRCUIT SBB05 (GY/RD) Ignition ON. Check the voltage between BCM C4227a-10, circuit SBB05 (GY/RD), harness side and ground. Check the voltage between BCM C 27a-11, circuit SBB05 (GY/RD), harness side and ground. Are the voltages greater than 10 volts? Yes: GO to E5 . No: REPAIR the circuit(s) as necessary. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal condition.
5. E5 CHECK FOR CORRECT BCM OPERATION NOTE: This pinpoint test step only addresses the 6-pin and 40-pin connectors for the BCM. It is not necessary to disconnect the high-voltage connectors when following this pinpoint test step procedure. Disconnect BCM electrical connector C 27a. Check for: corrosion. pushed-out pins. Connect BCM electrical connector C 27a and make sure it seats correctly. Operate the system and verify the concern is still present. Is the concern still present? Yes: INSTALL a new HVTB. REFER to «HIGH-VOLTAGE TRACTION BATTERY»(ref-344108-S23562780222009101600000) . TEST the system for normal operation. 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.

With the engine running, the battery power off (BPO) function may be triggered by the front and/or rear Inertia Fuel Shutoff (IFS) switches opening, a high-voltage interlock circuit opening or the electrical interlock (EL I) circuit opening (fuse protected by the Battery Junction Box (BJB) fuse 26 [5A]). The IFS switch opens and causes the BPO mode to occur, no DTCs are set. Also, if the IFS switch is open, a power reset indicator in the Instrument Cluster (IC) illuminates.

1. DTC P0A27 Hybrid Battery Power Off Circuit - the BCM will set this DTC if any of the following conditions are met: BCM detects a thermistor temperature greater than 57°C (134°F) for at least one second Contractor control is reported as closed while contractor status confirmed is reported as open for 10 seconds High Voltage Traction Battery (HVTB) is overheated. This pinpoint test is intended to diagnose the following: Fuse Circuitry (to the PCM) HVTB

Scheme 579

1. F1 CHECK THE BCM DTCs WARNING: Wear high-voltage insulated safety gloves and a face shield when working with high-voltage batteries or cables. The high-voltage insulated safety gloves should be of the appropriate safety and protection rating. Inspect the gloves before use and always wear them with the leather outer glove. Any hole in the rubber insulating glove is a potential entry point for high-voltage. Failure to follow these instructions may result in serious personal injury or death. WARNING: Turn OFF the ignition switch for a minimum of 5 minutes before removing high-voltage cables. High-voltage cables and wiring are orange in color. The nominal high-voltage traction battery voltage (HVTB) is 330 V DC. Failure to follow these instructions may result in serious personal injury or death. WARNING: Depower the high-voltage traction battery (HVTB) before carrying out any removal or installation procedures affecting the high-voltage battery system. Failure to follow this instruction may result in serious personal injury or death. WARNING: When servicing the high-voltage system, establish a buffer zone per the specified procedure. Failure to follow this instruction may result in serious personal injury or death. Check the recorded BCM DTCs from the continuous and on-demand self tests. Is DTC P0A1F also retrieved? Yes: REFER to the BCM DTC Chart to continue diagnosis of DTC P0A1F. No: GO to F2 .
2. F2 CHECK THE EL I CIRCUIT CBB26 (BU/WH) FOR AN OPEN OR SHORT TO GROUND Ignition OFF. Disconnect: BJB Fuse 26 (5A). Disconnect: BCM C4227a. Measure the resistance between the output cavity of BJB fuse 26 (5A) and BCM C4227a-14, circuit CBB26 (BU/WH), harness side; and between the output cavity of BJB fuse 26 (5A) and ground. Is the resistance less than 5 ohms between the BJB and the BCM; and greater than 10,000 ohms between the BJB and ground? Yes: VERIFY that the BJB fuse 26 (5A) is OK; if OK, GO to F3 . No: REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
3. F3 CHECK FOR CORRECT BCM OPERATION NOTE: This pinpoint test step only addresses the 6-pin and 40-pin connectors for the BCM. It is not necessary to disconnect the high-voltage connectors when following this pinpoint test step procedure. Disconnect BCM electrical connector C4227a. Check for: corrosion. pushed-out pins. Connect BCM electrical connector C4227a and make sure it seats correctly. Operate the system and verify the concern is still present. Is the concern still present? Yes: INSTALL a new HVTB. REFER to «HIGH-VOLTAGE TRACTION BATTERY»(ref-344108-S23562780222009101600000) . TEST the system for normal operation. 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.

With the engine running, the battery power off (BPO) function may be triggered by the front and/or rear Inertia Fuel Shutoff (IFS) switches opening, a high-voltage interlock circuit opening, the electrical interlock (EL I) circuit opening (fuse protected by the Battery Junction Box (BJB) fuse 26 [5A]) or if the contractor box within the Battery Control Module (BCM) requests a BPO mode. If the IFS switch opens and causes the BPO mode to occur, no DTCs are set. Also, if the IFS switch is open, a power reset indicator in the Instrument Cluster (IC) illuminates.

1. DTC C1862 Contractor Circuit Failure - The PCM monitors the frequency signal the BCM sends out on the BPO circuit CDC05 (GY/VT). With the ignition switch in the ON position and the engine ON or OFF (the engine must have run at least once after the key was cycled to ON), the BCM monitors the contractors continuously. During a power down (key OFF) sequence, one or both of the contractors may cause the BCM to set this DTC if they fail.

This pinpoint test is intended to diagnose the following

1. High Voltage Traction Battery (HVTB)
2. Service disconnect plug

The High Voltage Traction Battery (HVTB) fuse is part of the service disconnect plug. The Battery Control Module (BCM) monitors the HVTB fuse status at all times to determine if an open is present.

1. DTC P0A95 High-Voltage Fuse - The BCM cannot detect the difference between a blown fuse or if the service disconnect unplugged. Either condition will cause the BCM to set this DTC.

This pinpoint test is intended to diagnose the following

1. High-voltage fuse
2. Service disconnect plug
3. HVTB

With the engine running, the battery power off (BPO) function may be triggered by the front and/or rear Inertia Fuel Shutoff (IFS) switches opening, a high-voltage interlock circuit opening, the electrical interlock (EL I) circuit opening (fuse protected by the Battery Junction Box (BJB) fuse 26 [5A]) or if the contractor box within the Battery Control Module (BCM) requests a BPO mode. If the IFS switch opens and causes the BPO mode to occur, no DTCs are set. Also, if the IFS switch is open, a power reset indicator in the Instrument Cluster (IC) illuminates. With the ignition switch in the ON position and the engine ON or OFF (the engine must have run at least once after the key was cycled to ON), the BCM monitors the contractors continuously. During a power down (key OFF) sequence, one or both of the contractors may set this DTC if they fail.

1. DTC B2172 IFS Switch Input Circuit Open - If the BCM detects that the IFS switch circuit(s) is open, the DTC is set.

This pinpoint test is intended to diagnose the following

1. IFS switches
2. Circuitry
3. High Voltage Traction Battery (HVTB)

Scheme 580

Scheme 581

Scheme 582

1. I1 CHECK THE FRONT AND REAR IFS SWITCHES NOTE: The front IFS switch is located on the RH kick panel and the rear IFS switch is located near the RH rear tail lamp behind the jack. Check the front and rear IFS switch, verify that the reset buttons on the top of the switches are pushed (closed). Are the IFS switches okay? Yes: GO to I2 . No: INSTALL a new front and/or rear IFS switch. CLEAR the DTC. REPEAT the self-test. TEST the system for normal operation.
2. I2 CHECK FRONT AND REAR IFS CIRCUITS CE911 (VT/WH) AND CBB24 (VT-GN) FOR AN OPEN Ignition OFF. Disconnect: Front IFS switch C392. Disconnect: Rear IFS switch C4229. Ignition ON. Measure the voltage between front IFS switch C392-2, circuit CBB24 (VT/GN), harness side and ground. Measure the voltage between rear IFS switch C4229-2, circuit CE911 (VT/WH), harness side and ground. Is the voltage greater than 10 volts? Yes: GO to I3 . No: CHECK the IFS switch and circuits for a fault. If OK, REPAIR circuit CE911 (VT/WH). CLEAR the DTC. TEST the system for normal operation.
3. I3 CHECK THE IFS SWITCH POWER INPUT CIRCUITS Ignition OFF. Connect: Front IFS Switch C392. Connect: Rear IFS Switch C4229. Disconnect: BCM 34227a. Ignition ON. Check the voltage to the IFS switch input circuits between BCM C4227-7 and C4227-23, circuit CYB15 (GN) harness side and chassis ground. Are the voltages at least 10 volts? Yes: GO to I5 . No: GO to I4 .
4. I4 CHECK THE FRONT AND REAR IFS SWITCH RESISTANCES Ignition OFF. Measure the resistance between front IFS switch C392, pin 1 and pin 2, component side. Measure the resistance between rear IFS switch C4229, pin 1 and pin 2, component side. Are the resistances less than 5 ohms? Yes: GO to I5. No: INSTALL a new IFS switch(es). CLEAR the DTC. TEST the system for normal operation.
5. I5 CHECK THE BCM GROUND CIRCUIT NOTE: This pinpoint test step only addresses the 6-pin and 40-pin connectors for the BCM. It is not necessary to disconnect the high-voltage connectors when following this pinpoint test step procedure. Measure the voltage between BCM C4227a-7 and BCM C4227a-23 circuit CYB15 (GN) harness side and BCM C4227-a and/or BCM C4227a-0i1 circuit GD182 (BK/GY) harness side. Are the voltages at least 10 volts? Yes: INSTALL a new HVTB. REFER to «HIGH-VOLTAGE TRACTION BATTERY»(ref-344108-S23562780222009101600000) . TEST the system for normal operation. No: REPAIR circuit GD182 (BK/GY). CLEAR the DTC. TEST the system for normal operation.

With the engine running, the battery power off (BPO) function may be triggered by the front and/or rear Inertia Fuel Shutoff (IFS) switches opening, a high-voltage interlock circuit opening, the electrical interlock (EL I) circuit opening (fuse protected by the Battery Junction Box (BJB) fuse 26 [5A]) or if the contractor box within the Battery Control Module (BCM) requests a BPO mode. If the IFS switch opens and causes the BPO mode to occur, no DTCs are set. Also, if the IFS switch is open, a power reset indicator in the Instrument Cluster (IC) illuminates. With the ignition switch in the ON position and the engine ON or OFF (the engine must have run at least once after the key was cycled to ON), the BCM monitors the contractors continuously. During a power down (key OFF) sequence, one or both of the contractors may set this DTC if they fail.

Note. An intermittent high-voltage system interlock circuit short or open circuit can cause DTC P0A0E to be set in continuous memory.

1. DTC P0A0E High Voltage System Inter-Lock Circuit Intermittent - This DTC is set when the BCM cannot determine if the front/rear IFS switches or the high-voltage system interlock circuit is the source of the intermittent fault.

This pinpoint test is intended to diagnose the following

1. IFS switches
2. Circuitry
3. High-voltage system interlock circuit

With the ignition switch in the ON position and the engine ON or OFF (the engine must have run at least once after the key was cycled to ON), the Battery Control Module (BCM) monitors the electrical isolation (leakage resistance) between the high-voltage system and the vehicle chassis. A resistance value of less than 190,000 ohms (for 10 seconds or greater) is a failure. The normal resistance value is between 950,000-1,330,000 ohms.

1. DTC P0AA6 Hybrid Battery Voltage System Isolation Fault - If the BCM detects a high-voltage system leakage of less than 190,000 ohms for 10 seconds or greater or if the BCM detects a high-voltage system leakage of less than 66,000 ohms (with no time frame), the vehicle will not restart and the BCM will set this DTC.

This pinpoint is intended to diagnose the following

1. DC/DC converter wiring harness (high voltage)
2. DC/DC converter
3. High-voltage cables
4. High Voltage Traction Battery (HVTB)
5. Electronically Controlled Continuously Variable Transmission (eCVT)
6. Moisture/water penetration of high-voltage connectors

With the ignition switch in the ON position and the engine ON or OFF (the engine must have run at least once after the key was cycled to ON), the Battery Control Module (BCM) monitors the current, voltage, temperature and leakage resistance of the 50 individual nickel metal hydride battery modules within the High Voltage Traction Battery (HVTB). The BCM also controls the contractors.

1. DTC P0A1F Battery Energy Control Module Has Internal Errors - If there are any internal errors of the HVTB caused by sensor failure, control module failure or other serious related faults internal to the HVTB will cause the BCM to set this DTC.

This pinpoint test is intended to diagnose the following

1. Service disconnect plug
2. HVTB

The Battery Control Module (BCM) monitors the High Voltage Traction Battery (HVTB) state of charge when the key is in the ON or OFF position.

1. DTC P0A7D Hybrid Battery Pack State Of Charge Low - The BCM sets this DTC only when the ignition switch is first turned to the ON position, or when the ignition switch is in the START position. This condition may occur if the vehicle has been stored for an extended period of time.

This pinpoint test is intended to diagnose the following

1. HVTB
2. Vehicle condition

1. If it has been stored for an extended period of time.
2. Excessive engine start attempts.
3. Engine operation for an extended period of time.

At all times, the Battery Control Module (BCM) monitors the ignition run/start input circuit for voltage.

1. DTC P2533 Ignition Switch Run/Start Position Circuit - If the BCM does not detect voltage on the ignition run/start input circuit with the ignition switch in the ON position and the engine ON or OFF will cause this DTC to be set.

This pinpoint test is intended to diagnose the following

1. Fuse
2. Circuitry
3. High Voltage Traction Battery (HVTB)

Scheme 583

1. N1 RETRIEVE THE DTCs WARNING: Wear high-voltage insulated safety gloves and a face shield when working with high-voltage batteries or cables. The high-voltage insulated safety gloves should be of the appropriate safety and protection rating. Inspect the gloves before use and always wear them with the leather outer glove. Any hole in the rubber insulating glove is a potential entry point for high-voltage. Failure to follow these instructions may result in serious personal injury or death. WARNING: Turn OFF the ignition switch for a minimum of 5 minutes before removing high-voltage cables. High-voltage cables and wiring are orange in color. The nominal high-voltage traction battery voltage (HVTB) is 330 V DC. Failure to follow these instructions may result in serious personal injury or death. WARNING: Depower the high-voltage traction battery (HVTB) before carrying out any removal or installation procedures affecting the high-voltage battery system. Failure to follow this instruction may result in serious personal injury or death. WARNING: When servicing the high-voltage system, establish a buffer zone per the specified procedure. Failure to follow this instruction may result in serious personal injury or death. Enter the following diagnostic mode on the scan tool: BCM Self Test/Retrieve and Record On-Demand and Continuous Memory DTCs. Check the recorded BCM DTCs from the continuous and on-demand self tests. Is DTC P2612 also present? Yes: REFER to «CLIMATE CONTROL SYSTEM - GENERAL INFORMATION AND DIAGNOSTICS - HYBRID»(ref-344064) . No: GO to N2 .
2. N2 CHECK THE BCM IGNITION CIRCUIT INPUT AND BATTERY ZONE VALVE CONTROL CIRCUIT Ignition OFF. Disconnect: HVTB C4227a. Ignition ON. Measure the voltage between HVTB C4227a-19, circuit CBB23 (BN/YE), harness side and ground. Measure the voltage between HVTB C4227a-33, circuit CYB14 (GY/OG), harness side and ground. Are the voltage 10 volts or greater? Yes: GO to N3 . No: If circuit CBB23 (BN/YE) or both circuits CBB23 (BN/YE) and CYB14 (GY/OG) have less than 10 volts, VERIFY that the Smart Junction Box (SJB) fuse 27 (20A) is OK; if OK, REPAIR the circuit as necessary. CLEAR the DTCs. REPEAT the self-test. If only circuit CYB14 (GY/OG), CHECK the battery zone valve control. REFER to Diagnosis and Testing in «CLIMATE CONTROL SYSTEM - GENERAL INFORMATION AND DIAGNOSTICS - HYBRID»(ref-344064) .
3. N3 CHECK FOR CORRECT BCM OPERATION NOTE: This pinpoint test step only addresses the 6-pin and 40-pin connectors for the BCM. It is not necessary to disconnect the high-voltage connectors when following this pinpoint test step procedure. Disconnect BCM electrical connector C4227a. Check for: corrosion. pushed-out pins. Connect BCM electrical connector C4227a and make sure it seats correctly. Operate the system and verify the concern is still present. Is the concern still present? Yes: INSTALL a new HVTB. REFER to «HIGH-VOLTAGE TRACTION BATTERY»(ref-344108-S23562780222009101600000) . TEST the system for normal operation. 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.

When the key is turned to the ON position, the PCM sends a request to the Battery Control Module (BCM) over the Controller Area Network (CAN) communication link to close the High Voltage Traction Battery (HVTB) contractors.

1. DTC B1143 Excessive Battery Contractor Close Requests - If the PCM sends 100 requests in 4 minutes (or less) requests to close the HVTB contractors the BCM will set this DTC.

This pinpoint test is intended to diagnose the following

1. Rapid key cycling/excessive contractor close requests
2. CAN communication link
3. PCM
4. BCM
5. Real-time clock