Lexus ES manuals

Lexus ES: Hybrid/EV Battery Internal Electronic Failure (P31B549)

DESCRIPTION

The battery ECU assembly monitors its internal operation and will store these DTCs when it detects an internal malfunction.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

MIL

Warning Indicate

P31B549

Hybrid/EV Battery Internal Electronic Failure

An abnormal signal is detected by the battery ECU assembly (excessive discharging current).

(1 trip detection logic)

Hybrid vehicle control ECU

Does not come on

Master Warning Light:

Comes on

Related Data List

DTC No.

Data List

P31B549

Hybrid/EV Battery Current

CONFIRMATION DRIVING PATTERN

HINT:

After repairs have been completed, clear the DTCs and then check that the vehicle has returned to normal by performing the following All Readiness check procedure.

Click here

  1. Connect the Techstream to the DLC3.
  2. Turn the power switch on (IG) and turn the Techstream on.
  3. Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).
  4. Turn the power switch off and wait for 2 minutes or more.
  5. Turn the power switch on (IG) and turn the Techstream on.
  6. Drive the vehicle on urban roads for approximately 10 minutes.
  7. Enter the following menus: Powertrain / HV battery / Utility / All Readiness.
  8. Check the DTC judgment result.

    HINT:

    • If the judgment result shows NORMAL, the system is normal.
    • If the judgment result shows ABNORMAL, the system has a malfunction.
    • If the judgment result shows INCOMPLETE or N/A, perform driving pattern again.

PROCEDURE

1.

CHECK DTC OUTPUT (HV BATTERY, HYBRID CONTROL)

(a) Connect the Techstream to the DLC3.

(b) Turn the power switch on (IG).

(c) Enter the following menus: Powertrain / HV Battery and Hybrid Control / Trouble Codes.

(d) Check for DTCs.

Powertrain > HV Battery > Trouble Codes Powertrain > Hybrid Control > Trouble Codes

Result

Proceed to

"P31B549" only is output.

A

DTCs except "P31B549" of hybrid battery system are output.

B

DTCs except "P31B549" of hybrid control system are output.

C

(e) Turn the power switch off.

A

REPLACE HYBRID VEHICLE CONTROL ECU

B

GO TO DTC CHART (HYBRID BATTERY SYSTEM)

C

GO TO DTC CHART (HYBRID CONTROL SYSTEM)

READ NEXT:

 Hybrid/EV Battery Stack 1 Circuit Resistance Out of Range (P33DA1E,P33DB1E)

DESCRIPTION The HV battery is composed of 70 cells (3.7 V each) in series. The battery ECU assembly monitors the internal resistance of each HV battery cell to detect malfunctions of the HV battery.

 Hybrid/EV Battery Stack 1 Circuit Resistance Above Threshold (P33E01B,P33E11B)

DESCRIPTION The HV battery is composed of 70 cells (3.7 V each) in series. The battery ECU assembly monitors the internal resistance of each HV battery cell to detect malfunctions of the HV battery.

 (Extreme) Hybrid/EV Battery Stack 1 Cell Circuit Voltage Below Threshold (P33EC16,P33ED16)

DESCRIPTION If the voltage of an HV battery cell is lower than the threshold for a certain amount of time, the battery ECU assembly will interpret this as a malfunction. DTC No. Detection Item

SEE MORE:

 General maintenance

Listed below are the general maintenance items that should be performed at the intervals specified in the "Warranty and Service Guide" or "Owner's Manual Supplement". It is recommended that any problem you notice should be brought to the attention of your Lexus dealer or qualified service

 Installation

INSTALLATION CAUTION / NOTICE / HINT HINT: Use the same procedure for the RH side and LH side. The following procedure is for the LH side. PROCEDURE 1. INSTALL SST (w/o AVS) (a) Align the slot on end of the shock rod of the front shock absorber assembly as shown in the illustration. NOTICE:

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