W/Harness Inspection

HEV Battery System

P1B74 High Voltage Battery Voltage Sensor Circuit - Inspection/Repair:_:W/Harness Inspection

Terminal & Connector Inspection

1. Many malfunctions in the electrical system are caused by poor harness and terminals.
Faults can also be caused by interference from other electrical systems, and mechanical or chemical damage.
2. Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage.
3. Has a problem been found?






Hybrid Battery 72 cell voltage inspection

Hybrid Battery 72 cell voltage inspection
1. Ignition ON (SSB LED "BLUE"), in "Current Data" record any battery cell numbers under 0.5 V among 72 cells.
2. Disconnect Safety Plug, then check terminal voltage drop down is less than 30 V.
3. Check for looseness between battery module assembly and BMS ECU, poor connection, bent, corrosion, contamination, deformation and damage. If necessary, repair or replace as necessary then, go to "Verification of Vehicle Repair" procedure.
4. Confirm that battery cell voltage going to the BMS ECU is really under 0.5 voltage by measuring the rear side of BMS connector.
- If measured cell voltage is less than 0.5 V :
Check for open circuit in the each cell wire going to the BMS ECU from High Voltage battery.
If it is open, repair or replace as necessary, then, go to "Verification of Vehicle Repair" Procedure.
- Measured cell voltage is continuously less than 0.5 V, after Inspection for open in harness and repair, replace battery pack assembly. (Internal Sensing Circuit "OPEN" or Battery over discharge status)
- Measured cell voltage is higher than 2 V This is a fault of BMS ECM itself or a history DTC. Go to "Verification of Vehicle Repair" procedure.
- Measured cell voltage is higher than 2 V.
This is a fault of BMS ECM itself or a history DTC. Go to "Verification of Vehicle Repair" procedure.

Specification : Battery Cell Voltage range with No DTC : 1.5 - 4.8 V
Hybrid Battery 50 - 60% (State of Charge) : Approx. 3.75 V
** Notice : It is very difficult to judge whether it is good or not only with battery cell voltage in the specific charging status. Because voltage will be changeable in operating temperature according to SOC, voltage, temperature and current.

WARNING:
** Warning & Notice
Hybrid Battery system uses around 270 V voltage.
It may cause death or damage due to electrical shock, if you do not follow below Instructions.
▪ Follows instructions of workshop manual.
▪ Wear and use insulated gloves and tools.
▪ IG "OFF", Disconnect ground cable of auxiliary battery and "OFF" the safety connector of the high voltage battery.
▪ Check high voltage terminal on Power Relay Assembly is lower than 30 V.
▪ Be careful that it should not be short between terminals when measuring battery cell voltage. You may be injured due to spark, parts damage or electrical shock.
▪ Metallic material cause high voltage short that may cause damage of life or vehicle. Therefore, get rid of all the metallic material before working. (Metallic Material : Watch, Ring, any metallic products etc.)
▪ After disconnect W/H goes to BMS ECU from High voltage battery, be careful not to happen short between exposed terminal and terminal on high voltage connector.




















5. Is the measured value within specification?





Inspection with Analysis of Current Data
1. IG KEY OFF.
2. Connect the scantool to the DLC 16 pin Connector at the lower panel of the driver side.
3. After engine starting, select "the current data" item in the scantool.
4. Check "Hybrid battery pack voltage" and "battery cell voltage 1 - 72" in current data while engine ON or EV mode with acceleration.

Specification : 1 battery cell voltage (V) : 3.75 V (Discharge : 2.75 V, Full charge : 4.3 V)
Battery Pack voltage (V) : 270 V (Discharge : 198 V, Full Charge : 309 V)
























Fig.1) Hybrid battery SOC 46% : Battery voltage is detected around 271.5 V after engine ON and acceleration.
Fig.2) Hybrid battery soc 46% : Battery cell voltage is detected around 3.76 - 3.8 V after engine ON with acceleration.
Fig.3) Hybrid battery soc 46% : Battery cell voltage (1 - 17 cell) is detected around 3.76 - 3.8 V after Engine ON with acceleration.
Fig.4) Hybrid battery soc 46% : Battery cell voltage (18 - 38 cell) is detected around 3.76 - 3.8 V after engine "ON" with acceleration.
Fig.5) Hybrid battery soc 46% : Battery cell voltage (39 - 59 cell) is detected around 3.76 - 3.8 V after Engine "ON" with acceleration.
Fig.6) Hybrid battery SOC 46% : Battery cell voltage (59 - 72 cell) is detected around 3.76 - 3.8 V after engine "ON" with acceleration.
5. Are measured values within specification?