DESCRIPTION
The hybrid vehicle control ECU assembly has a self-diagnosis system. If the computer, hybrid control system, or a component is not working properly, the ECU records the conditions that relate to the fault. The ECU also illuminates the master warning in the combination meter assembly and provides other appropriate messages on the multi-information display, such as the HV system warning message, HV battery warning message, or discharge warning message.
CHINA NATIONWIDE STAGE 6
When troubleshooting On-Board Diagnostic (OBD) vehicles, the vehicle must be connected to the scan tool (complying with ISO 15765-4). Various data output from the vehicle's computer can then be read.
OBD regulations require that the vehicle's on-board computer illuminate the Malfunction Indicator Lamp (MIL) on the instrument panel when the computer detects a malfunction in:
The emission control system and components.
The powertrain control components which affect vehicle emissions.
The computer.
In addition, the applicable Diagnostic Trouble Codes (DTCs) prescribed by ISO 15765-4 are stored in the computer memory. If the malfunction does not reoccur in 3 consecutive trips, the MIL turns off automatically but the DTCs remain stored in the computer memory.
To check DTCs, connect the GTS or scan tool to the Data Link Connector 3 (DLC3) of the vehicle.
The scan tool displays DTCs, the Freeze Frame Data and a variety of hybrid control data.
The DTCs and Freeze Frame Data can be cleared using the scan tool.
2 TRIP DETECTION LOGIC
When a malfunction is first detected, the malfunction is temporarily stored in the hybrid vehicle control ECU assembly memory (1st trip). If the same malfunction is detected during the next drive cycle, the MIL is illuminated (2nd trip).
FREEZE FRAME DATA
The hybrid vehicle control ECU assembly records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can be helpful in determining whether the vehicle was moving or stationary, whether the engine was warmed up or not, as well as other data recorded at the time of a malfunction.
AUXILIARY BATTERY VOLTAGE
| Switch Condition | Specified Condition |
|---|---|
| Power switch on (IG) | 11 to 14 V |
If voltage is below 11 V, recharge or replace the auxiliary battery.
After the power switch is turned off, there may be a waiting time before disconnecting the auxiliary negative (-) battery terminal.
When disconnecting and reconnecting the auxiliary battery.
When disconnecting and reconnecting the auxiliary battery, there is an automatic learning function that completes learning when the respective system is used.
MIL (Malfunction Indicator Lamp)
The MIL is illuminated when the power switch is first turned on (IG), before the READY light comes on.
When the READY indicator turns on, the MIL should turn off. If the MIL remains illuminated, the diagnosis system has detected a malfunction or abnormality in the system.
If the MIL is not illuminated when the power switch is first turned on (IG), check the MIL circuit.
for SFI System (for A25B-FXS): Click hereEngine / Hybrid System>A25B-FXS (ENGINE CONTROL)>SFI SYSTEM>MIL Circuit202304,999999,_51,_083340,_0402276,RM100000002B1P9,
for SFI System (for A25D-FXS): Click hereEngine / Hybrid System>A25D-FXS (ENGINE CONTROL)>SFI SYSTEM>MIL Circuit202304,999999,_51,_103786,_0477830,RM100000002B1PA,
for SFI System (for A25F-FXS): Click hereEngine / Hybrid System>A25F-FXS (ENGINE CONTROL)>SFI SYSTEM (Production date from 2021/08)>MIL Circuit202304,999999,_51,_105211,_0483212,RM100000002B1PB,
RELEVANT SYSTEMS CHECK
The inspection areas and outline of the inspection for each circuit are listed below.
| System to be Inspected | Malfunction Possibility | Inspection Content |
|---|---|---|
| Motor Resolver Circuit | Motor resolver signal | Open or short circuit in the motor resolver, connectors or cables |
| Motor High-voltage Circuit | Motor (MG2) output | Open or short circuit in the motor (MG2), connectors or cables |
| Rear Motor Resolver Circuit | Rear motor resolver signal | Open or short circuit in the rear motor resolver, connectors or cables |
| Rear Motor High-voltage Circuit | Rear motor (MGR) output | Open or short circuit in the rear motor (MGR), connectors or cables |
| Generator Resolver Circuit | Generator resolver signal | Open or short circuit in the generator resolver, connectors or cables |
| Generator High-voltage Circuit | Generator (MG1) output | Open or short circuit in the generator (MG1), connectors or cables |
| Inverter Low-voltage Circuit | Power supply voltage from +B or communication between hybrid vehicle control ECU assembly and motor generator control ECU | ·
Open or short circuit in communication line between hybrid vehicle control ECU assembly and motor generator control ECU ·
Open or short circuit in the +B or ground lines ·
Fuse is blown |
| HV Battery High-voltage Line Circuit | High voltage power supply from HV battery | Open or short circuit in the system main relay, connectors or cables |
| Cooling System | Temperature abnormally high | ·
Grille blockage ·
Whether coolant is present ·
Whether there is a possibility that coolant was frozen when malfunction occurs ·
Cooling hose blockage ·
HV radiator fan operation |
| Shutdown Signal Circuit | Shutdown signal | Open or short circuit in shutdown signal communication line between hybrid vehicle control ECU assembly and motor generator ECU |