P0AFA

P310 HYBRID BATTERY CONTROL: HYBRID BATTERY SYSTEM: P0AFA: Hybrid Battery System Voltage Low

DTC P0AFA - Hybrid Battery System Voltage Low

DESCRIPTION
- The HV battery uses nickel metal-hydride batteries and does not require external charging. The HV control ECU controls the SOC (state of charge) of the HV battery at a constant level during driving. The HV battery is composed of 30 modules, and each module consists of eight 1.2 V cells in series. The battery smart unit monitors battery block voltage at 15 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 in internal battery voltage sensor circuits of the battery smart unit and the wire harness between each battery block and battery smart unit. If the voltage at any of the battery blocks is out of the 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

CASE 1:





CASE 2:





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 5 minutes before touching any of the high-voltage connectors or terminals. After waiting for 5 minutes, check the voltage at the terminals in the inspection point in the inverter with converter assembly. The voltage should be 0 V before beginning work.
HINT: Waiting for at least 5 minutes is required to discharge the high-voltage capacitor inside the inverter with converter assembly.

PROCEDURE

1. CHECK DTC OUTPUT (DTC P0A1F IS OUTPUT)
(a) Connect the Techstream to the DLC3.
(b) Turn the ignition switch to the ON position.
(c) Select the following menu items: Powertrain / Hybrid Control / Trouble Codes.
(d) Read output DTCs Hybrid Battery System.
Result:






B -- GO TO DTC CHART (P0A1F)
A -- Continue to next step.
2. CHECK CONNECTOR CONNECTION CONDITION (BATTERY SMART UNIT)
CAUTION: Be sure to wear insulated gloves and protective goggles.





(a) Check the connections of the connectors shown in the illustration.
Result:






NG -- CONNECT SECURELY
OK -- Continue to next step.
3. REPLACE BATTERY SMART UNIT
(a) Replace the battery smart unit Components.
NEXT -- Continue to next step.
4. CLEAR DTC
(a) Connect Techstream to the DLC3.
(b) Turn the ignition switch to the ON position.
(c) Select the following menu items: Powertrain / Hybrid Control / Trouble Codes.
(d) Clear DTCs.
NEXT -- Continue to next step.
5. RECONFIRM DTC OUTPUT
(a) Connect the Techstream to the DLC3.
(b) Turn the ignition switch to the ON position.
(c) Select the following menu items: Powertrain / Hybrid Control / Trouble Codes.
(d) Read output DTCs Hybrid Battery System.
Result:






B -- REPLACE HV BATTERY
A -- RETURNS TO NORMAL OPERATION