Code No. P1A4B: Voltage Of Each Battery Cell Abnormal


TROUBLE JUDGMENT
Check Conditions
  • 3 seconds elapse after the electric motor switch is turned ON, or 3 seconds elapse after the main battery starts to be charged.
  • The absolute value of the current is less than 1 A.
  • The energy level gauge is more than 4 segments.
  • None of the following diagnosis codes occur at the same time.

  1. P1AA8: Local CAN (for main battery) signal time-out
  2. U1082: Local CAN (for main battery) bus off
Judgement Criterion
  • When the information that the difference is more than 0.2 V between the lowest battery cell voltage and the highest battery cell voltage is received for more than 5 seconds.

FAIL-SAFE AND BACKUP FUNCTION

  • Not available

PROBABLE CAUSE

  • The module (battery cell and CMU) in the main battery is failed.

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III data list

  • Item 33: largest difference between cell voltage
OK: 0.2 V less (electric motor switch: ON, also the energy level gauge of the combination meter has more than 4 segments.)

Q. Is the check result normal?
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions ).
Replace the main battery.