P0A05

P310 HYBRID VEHICLE CONTROL: HYBRID CONTROL SYSTEM: P0A05-776: Motor Electronics Coolant Pump Control Circuit / Open

DTC P0A05-776 - Motor Electronics Coolant Pump Control Circuit / Open

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.

WIRING DIAGRAM

INSPECTION PROCEDURE

PROCEDURE

1. 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 / Trouble Codes.
(d) Clear DTCs and freeze frame data.
(e) Select the following menu items: Powertrain / Hybrid Control / Active Test / Activate the Water Pump.
(f) 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 HARNESS AND CONNECTOR (WATER PUMP)
OK -- Continue to next step.
2. INSPECT HYBRID VEHICLE CONTROL ECU

(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 for pulse signals according to the table below.

OK:
The waveform appears as shown in the illustration.
OK -- READ OUTPUT DTC (HV)
NG -- Continue to next step.
3. 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.
4. INSPECT WATER PUMP W/ MOTOR & BRACKET ASSEMBLY

(a) Disconnect the W5 water pump connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:

NG -- REPLACE WATER PUMP W/ MOTOR & BRACKET ASSEMBLY
OK -- REPLACE HYBRID VEHICLE CONTROL ECU
5. CHECK HARNESS AND CONNECTOR (WATER PUMP)
(a) Turn the ignition switch off.

(b) Disconnect the W5 water pump w/ motor & bracket assembly connector.

NG -- CHECK FUSE (INV W/P)
OK -- Continue to next step.
6. 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.
7. 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 w/ motor & bracket assembly 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.
8. INSPECT HYBRID VEHICLE CONTROL ECU

(a) Connect the HV control ECU connector and water pump w/ motor & bracket assembly connector.
(b) Turn the ignition switch to the ON position.
(c) Measure the voltage according to the value(s) in the table below.
Standard Voltage:

OK -- INSPECT HYBRID VEHICLE CONTROL ECU
NG -- Continue to next step.
9. INSPECT WATER PUMP W/ MOTOR & BRACKET ASSEMBLY (SWP TERMINAL VOLTAGE)

(a) Disconnect the H29 connector from the HV control ECU.
(b) Turn the ignition switch to the ON position.
(c) Measure the voltage according to the value(s) in the table below.
Standard Voltage:

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

(a) Put the vehicle into the READY-on state.
(b) Measure the voltage according to the value(s) in the table below.
Standard Voltage:

OK -- REPLACE WATER PUMP W/ MOTOR & BRACKET ASSEMBLY
NG -- REPLACE HYBRID VEHICLE CONTROL ECU
11. READ OUTPUT DTC (HV)
(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 / Trouble Codes.
(d) Read output DTC. Hybrid Control System

Result:
DTC P0A05-776 is output.
YES -- REPLACE HYBRID VEHICLE CONTROL ECU
NO -- Continue to next step.
12. PERFORM REPRODUCTION TEST

(e) Perform the following reproduction tests. (Check for intermittent problems.)

OK:
The interval of pulse signal output is normal.
NG -- REPAIR OR REPLACE ABNORMAL PART
OK -- REPLACE WATER PUMP W/ MOTOR & BRACKET ASSEMBLY
13. CHECK FUSE (INV W/P) P0A01-725

NG -- REPLACE FUSE (INV W/P)
OK -- REPAIR OR REPLACE HARNESS OR CONNECTOR