P1556

L110 HYBRID VEHICLE CONTROL: HYBRID CONTROL SYSTEM: P1555-181: Reactor Temperature Sensor Circuit Low

DTC P1555-181 - Reactor Temperature Sensor Circuit Low

DTC P1556-182 - Reactor Temperature Sensor Circuit High

DESCRIPTION

The MG ECU located in the inverter with converter assembly detects the temperature of the reactor using a temperature sensor built into the inverter with converter assembly. The inverter cooling system is the same as that for MG2 or MG1, and operates independently of the engine cooling system. The MG ECU limits the load based on signals sent from the reactor temperature sensor in order to check the effect of the inverter cooling system and prevent overheating. The ECU also detects malfunctions in the reactor temperature sensor.
HINT: The reactor is a component with characteristics that resist changes in the current flow. The reactor will attempt to maintain the current flow. This characteristic stabilizes the current flowing to the HV battery. The reactor is also used to boost the battery voltage which is supplied to the inverters.





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 10 minutes before touching any of the high-voltage connectors or terminals. After waiting, check the voltage at the inspection point in the inverter with converter assembly. The voltage should be 0 V before beginning work.
HINT: Waiting for at least 10 minutes is required to discharge the high-voltage capacitor inside the inverter with converter assembly.

PROCEDURE

1. CHECK DTC OUTPUT (HV)
(a) Connect the Techstream to the DLC3.
(b) Turn the power switch on (IG).
(c) Select the following menu items: Powertrain / Hybrid Control / Trouble Codes.
(d) Check if DTCs are output.
Result:






YES -- GO TO DTC CHART
NO -- REPLACE INVERTER WITH CONVERTER ASSEMBLY