P0AFA

HYBRID BATTERY CONTROL: HYBRID BATTERY SYSTEM: P0AFA-123: Hybrid Battery System Voltage Low

DTC P0AFA-123 - Hybrid Battery System Voltage Low

DESCRIPTION
The hybrid vehicle control ECU controls the SOC (state of charge) of the HV battery at a constant level while driving. The HV battery is composed of 34 modules, and each module consists of six 1.2 V cells in series. The battery smart unit monitors battery block voltage at 17 locations. Each battery block is composed of 2 modules in a set.










MONITOR DESCRIPTION

The battery smart unit monitors a voltage of the battery blocks to detect an open malfunction in internal battery voltage sensor circuits of the battery smart unit and the wire harness between each battery block and battery smart unit. If a voltage at one of the battery blocks is below a standard level or of all the battery blocks is within a specified range, the battery smart unit judges that there is an open in the internal sensor circuit(s) or wire harness. The HV control ECU then illuminates the MIL and sets a DTC.

MONITOR STRATEGY





TYPICAL ENABLING CONDITIONS





TYPICAL MALFUNCTION THRESHOLDS





COMPONENT OPERATING RANGE





INSPECTION PROCEDURE
CAUTION:
- Before inspecting the high-voltage system, take safety precautions such as wearing insulated gloves and removing the service plug grip to prevent electrical shocks. After removing the service plug grip, put it in your pocket to prevent other technicians from accidentally reconnecting it while you are working on the high-voltage system.
- After disconnecting the service plug grip, wait for at least 10 minutes before touching any of the high-voltage connectors or terminals.
HINT: Waiting for at least 10 minutes is required to discharge the high-voltage capacitor inside the inverter with converter assembly.

PROCEDURE

1. CHECK FOR DTCS (DTC P0A1F-123 IS OUTPUT)
(a) Connect Techstream to the DLC3.
(b) Turn the power switch on (IG).
(c) Select the following menu items: Powertrain / Hybrid Control / Trouble Codes.
(d) Check if DTCs are output.
Result:
DTC P0A1F-123 is output.
YES -- GO TO INSPECTION PROCEDURE RELEVANT TO OUTPUT DTC
NO -- Continue to next step.
2. CHECK CONNECTOR CONNECTION CONDITION (BATTERY SMART UNIT)
CAUTION: Be sure to wear insulated gloves.
(a) Remove the service plug grip Removal.
(b) Remove the HV relay assembly Removal.




(c) Check the connection of connector r3 of the battery smart unit.
OK:
The connector is connected securely and there are no contact problems.
NG -- CONNECT SECURELY
OK -- Continue to next step.
3. REPLACE BATTERY SMART UNIT Components.
NEXT -- Continue to next step.
4. CLEAR DTC
(a) Connect Techstream to the DLC3.
(b) Turn the power switch on (IG).
(c) Select the following menu items: Powertrain / Hybrid Control / Trouble Codes.
(d) Clear DTCs.
NEXT -- Continue to next step.
5. RECONFIRM DTC OUTPUT
(a) Select the following menu items: Powertrain / Hybrid Control / Trouble Codes.
(b) Check if DTCs are output.
Result:
DTC P0AFA-123 is output.
YES -- REPLACE HV BATTERY
NO -- COMPLETED