P0ADB

P310 HYBRID VEHICLE CONTROL: HYBRID CONTROL SYSTEM: P0ADB-227: Hybrid Battery Positive Contactor Circuit Stuck Open

DTC P0ADB-227 - Hybrid Battery Positive Contactor Circuit Stuck Open

DTC P0ADC-226 - Hybrid Battery Positive Contactor Circuit Stuck Closed

DESCRIPTION

The SMRs (System Main Relays), installed in the HV relay assembly, connect and disconnect the high-voltage power supply circuit in accordance with requests from the hybrid vehicle control ECU. To ensure reliable operation, there are three SMRs in total (one for the negative side and two for the positive side).





To connect the high-voltage power supply circuit, SMR1 and SMR3 turn on initially. Then, SMR2 turns on and SMR1 turns off. This process protects the circuit from the high-voltage surge current by allowing current to flow via the limiting resistor. To disconnect the high-voltage power supply circuit, SMR2 and SMR3 turn off in that order. The hybrid vehicle control ECU checks that the relays have turned off properly.
The hybrid vehicle control ECU monitors operation of the SMRs (CON1, CON2, CON3) to check for malfunctions.







WIRING DIAGRAM






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 disconnecting the service plug grip, wait for at least 5 minutes before touching any of the high-voltage connectors or terminals. After waiting for 5 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.
HINT: Waiting for at least 5 minutes is required to discharge the high-voltage capacitor inside the inverter with converter assembly.

PROCEDURE

1. CHECK HARNESS AND CONNECTOR (HYBRID VEHICLE CONTROL ECU - HV RELAY ASSEMBLY)
CAUTION: Be sure to wear insulated gloves.
(a) Turn the power switch off.
(b) Remove the service plug grip Removal.
NOTE: 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.
(c) Disconnect connector D36 from the hybrid vehicle control ECU.
(d) Disconnect connector z20 from the HV relay assembly.
(e) Turn the power switch on (IG).





(f) Measure the voltage according to the value(s) in the table below.
HINT: Turning the power switch on (IG) with the service plug grip removed causes an interlock switch system DTC (P0A0D-350) to be set.

Standard voltage :





(g) Turn the power switch off.
(h) Measure the resistance according to the value(s) in the table below.
Standard resistance (Check for open):






Standard resistance (Check for short):






NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
2. CHECK HV RELAY ASSEMBLY (SMR2)
CAUTION: Be sure to wear insulated gloves.
(a) Turn the power switch off.
(b) Remove the service plug grip Removal.
NOTE: 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.
(c) Remove the HV relay assembly from the vehicle Removal.





(d) Measure the resistance according to the value(s) in the table below.
Standard resistance:





(e) Measure the resistance according to the value(s) in the table below.
Standard resistance:






NG -- REPLACE HV RELAY ASSEMBLY
OK -- REPLACE HYBRID VEHICLE CONTROL ECU