P0C76
HYBRID / BATTERY CONTROL: HYBRID CONTROL SYSTEM: P0C76-523: Hybrid Battery System Discharge Time Too Long
P0C76-523 - Hybrid Battery System Discharge Time Too Long
DESCRIPTION
Refer to the description for DTC P0A78-266 P0A78-266.
HINT
When the power switch is turned off, the MG ECU applies current to MG2 in a way that does not generate torque, in order to discharge the residual voltage in the inverter. When the hybrid system is normal, the VH value is almost 0 V after discharge. This DTC will be stored if the VH value is more than the specified value after discharge.
INSPECTION PROCEDURE
CAUTION:
- Before inspecting the high-voltage system or disconnecting the low voltage connector of the inverter with converter assembly, 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 removing the service plug grip, wait for at least 10 minutes before touching any of the high-voltage connectors or terminals. After waiting for 10 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 Hybrid Control System: Precaution.
HINT
Waiting for at least 10 minutes is required to discharge the high-voltage capacitor inside the inverter with converter assembly.
NOTICE:
After turning the power switch off, waiting time may be required before disconnecting the cable from the negative (-) auxiliary battery terminal. Therefore, make sure to read the disconnecting the cable from the negative (-) auxiliary battery terminal notices before proceeding with work Service Precautions.
PROCEDURE
1. CHECK DTC OUTPUT (HYBRID CONTROL)
(a) Connect the Techstream to the DLC3.
(b) Turn the power switch on (IG).
(c) Enter the following menus: Powertrain / Hybrid Control / Trouble Codes.
(d) Check if DTCs are output.
Result:
HINT
- *1: If any INF codes are output for this DTC, refer to the corresponding diagnostic procedure.
- P0C76-523 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.
(e) Turn the power switch off.
B -- GO TO DTC CHART (HYBRID CONTROL SYSTEM) Hybrid Control System
A -- Continue to next step.
2. CHECK DTC OUTPUT (HYBRID CONTROL)
(a) Connect the Techstream to the DLC3.
(b) Turn the power switch on (IG).
(c) Enter the following menus: Powertrain / Hybrid Control / Trouble Codes.
(d) Check if DTCs are output.
Result:
HINT
When the DTCs listed in the table above are also output, there may be a short between the HSDN (MG shut down signal) circuit and power circuit.
(e) Turn the power switch off.
B -- REPLACE INVERTER WITH CONVERTER ASSEMBLY Components
A -- Continue to next step.
3. CHECK POWER MANAGEMENT CONTROL ECU
(a) Turn the power switch on (IG).
(b) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
Text in Illustration
(c) Turn the power switch off.
NG -- CHECK HARNESS AND CONNECTOR (POWER MANAGEMENT CONTROL ECU - INVERTER WITH CONVERTER ASSEMBLY)
OK -- REPLACE INVERTER WITH CONVERTER ASSEMBLY Components
4. CHECK HARNESS AND CONNECTOR (POWER MANAGEMENT CONTROL ECU - INVERTER WITH CONVERTER ASSEMBLY)
CAUTION:
Be sure to wear insulated gloves.
(a) Check that the service plug grip is not installed.
NOTICE:
After removing the service plug grip, do not turn the power switch on (READY), unless instructed by the repair manual because this may cause a malfunction.
(b) Disconnect connector A14 from the inverter with converter assembly.
(c) Disconnect connector A39 from the power management control ECU.
(d) Connect the cable to the negative (-) auxiliary battery terminal.
(e) Turn the power switch on (IG).
(f) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
Text in Illustration
NOTICE:
Turning the power switch on (IG) with the connector disconnected causes other DTCs to be stored. Clear the DTCs after performing this inspection.
(g) Turn the power switch off.
(h) Disconnect the cable from the negative (-) auxiliary battery terminal.
(i) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
(j) Connect the inverter with converter assembly connector.
(k) Connect the power management control ECU connector.
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
5. CHECK INVERTER WITH CONVERTER ASSEMBLY
CAUTION:
Be sure to wear insulated gloves.
(a) Check that the service plug grip is not installed.
NOTICE:
After removing the service plug grip, do not turn the power switch on (READY), unless instructed by the repair manual because this may cause a malfunction.
(b) Disconnect connector A14 from the inverter with converter assembly.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Text in Illustration
(d) Connect the inverter with converter assembly connector.
NG -- REPLACE INVERTER WITH CONVERTER ASSEMBLY Components
OK -- REPLACE POWER MANAGEMENT CONTROL ECU Components