P0A01-726

P310 HYBRID VEHICLE CONTROL: HYBRID CONTROL SYSTEM: P0A01-725: Motor Electronics Coolant Temperature Sensor Circuit Range / Performance

DTC P0A01-725 - Motor Electronics Coolant Temperature Sensor Circuit Range / Performance

DTC P0A01-726 - Motor Electronics Coolant Temperature Sensor Circuit Range / Performance

DESCRIPTION

The HV control ECU detects coolant temperature (for Inverter) through the coolant temperature sensor built into the inverter. The inverter cooling system is the same as that for the Motor or Generator, and operates independently of the engine cooling system. The HV control ECU controls the inverter cooling system to prevent overheating based on signals from the coolant temperature sensor. The ECU also monitors cooling system operation and detects malfunctions in the HV coolant temperature sensor and the circuit.






INSPECTION PROCEDURE
CAUTION:
- Before inspecting the high-voltage system, take safety precautions to prevent electrical shocks, such as wearing insulated gloves and removing the service plug grip. After removing the service plug grip, put it in your pocket to prevent other technicians from 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.
HINT: At least 5 minutes is required to discharge the high-voltage capacitor inside the w/ converter inverter assembly.

PROCEDURE

1. DTC OUTPUT (HV)
(a) Connect the Techstream to the DLC3.
(b) Put the vehicle into the READY-on state and wait for 10 seconds or more.
(c) Select the following menu items: Powertrain / Hybrid Control / Trouble Codes.
(d) Read output DTC. Hybrid Control System

Result:
The DTC shown in the table below is output






YES -- GO TO DTC CHART
NO -- Continue to next step.
2. CHECK QUANTITY OF COOLANT (FOR INVERTER)
(a) Check the coolant level.
OK:
There is a sufficient amount of coolant.
NG -- CHECK FOR COOLANT LEAKS AND ADD COOLANT (FOR INVERTER)
OK -- Continue to next step.
3. CHECK COOLANT HOSE





(a) Check if the hoses of the cooling system are not bent or clogged.
OK:
The hoses of the cooling system are not bent or clogged.
NG -- CORRECT TO NORMAL CONDITION
OK -- Continue to next step.
4. CHECK CONNECTION CONDITION OF WATER PUMP CONNECTOR (LOOSENESS AND POOR CONTACT)





(a) Check the connection of the water pump w/ motor & bracket assembly connector.
OK:
Connector is connected securely and there is no poor connection.
NG -- CONNECT SECURELY
OK -- Continue to next step.
5. PERFORM ACTIVE TEST BY TECHSTREAM (WATER PUMP)
(a) Connect the Techstream to the DLC3.
(b) Turn the ignition switch to the ON position.
(c) Select the following menu items: Powertrain / Hybrid Control / Active Test / Activate the Water Pump.
(d) During the "Activate the Water Pump" active test, check operation of the water pump.
OK:
There are ripples in the reservoir tank coolant.
HINT: The water pump is also activated in the READY-on state.

NG -- CHECK FUSE (INV W/P)
OK -- Continue to next step.
6. PERFORM ACTIVE TEST BY TECHSTREAM (COOLING FAN)
(a) Connect the Techstream to the DLC3.
(b) Turn the ignition switch to the ON position.
(c) Select the following menu items: Powertrain / Engine and ECT / Active Test / Control the Electric Cooling Fan.
(d) Perform the "Control the Electric Cooling Fan" active test.
OK:
The electric cooling fan rotates.
NG -- CHECK COOLING FAN CIRCUIT
OK -- Continue to next step.
7. CHECK CONNECTION CONDITION OF MG ECU CONNECTOR (LOOSENESS AND POOR CONTACT)
CAUTION: Be sure to wear insulated gloves.
(a) Turn the ignition switch off and remove the service plug grip. Hybrid Control System

NOTE: Do not put the vehicle into the READY-on state with the service plug grip removed as this may cause a malfunction.
(b) Remove the inverter cover. Components

NOTICE:
- Wrap the interlock round terminal for the inverter cover with vinyl tape to prevent it from shorting to ground.
- Be sure to prevent water in the reservoir tank from entering the inverter.
- Removing the inverter cover causes the MG ECU board to be exposed. Therefore, temporarily install the inverter cover for each area to be inspected.





(c) Check the connections of all MG ECU connectors.
OK:
Connectors are connected securely and there is no poor connection.
NG -- CONNECT SECURELY
OK -- REPLACE W/ CONVERTER INVERTER ASSEMBLY
8. CHECK FUSE (INV W/P)





(a) Check if there is an open circuit in the fuse (INV W/P) in the engine room relay block.
OK:
There is no open circuit in the fuse (INV W/P).
HINT: If the result is NG, replace the fuse (INV W/P) with a new one.

NG -- REPLACE FUSE (INV W/P)
OK -- Continue to next step.
9. CHECK HARNESS AND CONNECTOR (HV CONTROL ECU - WATER PUMP)





(a) Turn the ignition switch off.
(b) Disconnect the H29 connector from the HV control ECU.
(c) Disconnect the W5 water pump connector.
(d) 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.
10. CHECK HYBRID VEHICLE CONTROL ECU P0A93-346

OK -- INSPECT HYBRID VEHICLE CONTROL ECU
NG -- Continue to next step.
11. INSPECT WATER PUMP W/MOTOR & BRACKET ASSEMBLY P0A93-346

NG -- REPLACE WATER PUMP W/ MOTOR & BRACKET ASSEMBLY
OK -- REPLACE HYBRID VEHICLE CONTROL ECU
12. INSPECT HYBRID VEHICLE CONTROL ECU P0A93-346

NG -- REPLACE HYBRID VEHICLE CONTROL ECU
OK -- REPLACE WATER PUMP W/ MOTOR & BRACKET ASSEMBLY