DESCRIPTION
The battery smart unit (battery energy control module) sends HV battery voltage information to the power management control ECU via serial communication.
| DTC No. | INF Code | DTC Detection Condition | Trouble Area |
|---|---|---|---|
| P0AFC | 129 | HV battery voltage circuit malfunction | Battery smart unit |
INSPECTION PROCEDURE
Note
Performing the check procedures for a long time with the shift lever in the N position may cause DTC P3000-388 to be set.
Tech Tips
If, after performing troubleshooting, it is necessary to replace the battery smart unit, voltages need to be confirmed after installing the new battery smart unit. To confirm normal operation, compare the HV battery voltage (PWR RESOURCE VB), pre-boost voltage (VL), and post-boost voltage (VH) in the Data List with the power switch on (READY) and the shift lever in the N position. When the system is normal, the PWR RESOURCE VB, VL, and VH values should be almost equal (voltage boosting will not occur when the shift lever is in neutral). If the difference between each voltage exceeds the values specified below, there is a malfunction in the battery smart unit.
| Inspection voltage | Maximum voltage difference |
|---|---|
| Difference between HV battery voltage (PWR RESOURCE VB) and pre-boost voltage (VL) | 40V or higher |
| Difference between HV battery voltage (PWR RESOURCE VB) and post-boost voltage (VH) | 40V or higher |
| Difference between pre-boost voltage (VL) and post-boost voltage (VH) | 50V or higher |
PROCEDURE
CHECK DTC OUTPUT (HV)
Connect the intelligent tester to the DLC3.
Turn the power switch on (IG).
Enter the following menus: Powertrain / Hybrid Control / Trouble Codes.
Check if DTCs are output.
| Result | ||||||
|---|---|---|---|---|---|---|
|
| DTC No. | Relevant Diagnosis |
|---|---|
| P0A1A-151, 155, 156, 658, 659 | Generator Control Module |
| P0A1B-164, 193, 661, 786 | Drive Motor "A" Control Module |
| P0A1D-148 | Hybrid Powertrain Control Module |
| P2511-149 | HV CPU Power Relay Sense Circuit Intermittent No Continuity |
| P324E-788 | MG-ECU Power Relay Intermittent Circuit |
| U0110 (all INF codes)*1 | Lost Communication with Drive Motor Control Module "A" |
Tech Tips
*1: If any INF codes are output for this DTC, refer to the corresponding diagnostic procedure.
P0AFC-129 may be output due to a malfunction which causes the DTCs in the table above to be output. In this case, first troubleshoot the output DTCs in the table above. Then, perform a reproduction test to check that no DTCs are output.
Turn the power switch off.
| B |
|
GO TO DTC CHART Click here |
| A |
|
REPLACE BATTERY SMART UNIT Click here