Inspection Procedure

WARNING: This page is about a different car, the 2006 Lexus RX 400h. However, it is still accessible from the selected car via links, so may be relevant.

NOTE:

When troubleshooting the oil pump w/ motor assembly, check for the following conditions:
- ATF temperature inside the oil cooler is 5°C (41°F) or more.
- Value of the ambient temperature sensor is 5°C (41°F) or more.

READ OUTPUT DTC (HV)
1. Connect the intelligent tester to the DLC3.
2. Turn the ignition switch to the ON position.
3. Select the following menu items: DIAGNOSIS / OBD/ MOBD / HV ECU / DTC INFO / CURRENT CODES.
4. Read output DTCs. (See DTC CHECK / CLEAR )
  Result:
  
  DTC P0A08-264 is output.
YES: GO TO DIAGNOSTIC TROUBLE CODE CHART

NO: GO TO NEXT STEP
RECONFIRM OUTPUT DTC (HV)
1. Connect the intelligent tester to the DLC3.
2. Turn the ignition switch to the ON position.
3. Select the following menu items: DIAGNOSIS / OBD/ MOBD / HV ECU / DTC INFO / CLEAR CODES.
4. Turn the ignition switch to the ON position, and select the following menu items: DIAGNOSIS / OBD/MOBD / HV ECU / DTC INFO / CURRENT CODES.
5. Read output DTCs. (See DTC CHECK / CLEAR )
  Result:
  
  DTC P0A08-264 is output again.
NO: CHECK FOR INTERMITTENT PROBLEMS

YES: GO TO NEXT STEP

CHECK HARNESS AND CONNECTOR (AUXILIARY BATTERY - OIL PUMP - BODY GROUND)

Disconnect the cable from the positive auxiliary battery terminal.
Remove the oil pump relay from the engine room R/B No. 4.
Disconnect the O9 oil pump w/ motor assembly connector.

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

Standard Resistance

AUXILIARY BATTERY - OIL PUMP - BODY GROUND

Tester Connection	Specified Value
Positive auxiliary battery terminal - Engine room R/B No. 4 OIL PUMP relay terminal 5	Below 2 Ω	R1
Engine room R/B No. 4 OIL PUMP relay terminal 5 - +B (O9-4)	Below 2 Ω	R2
GND (O9-1) - Body ground	Below 2 Ω	R3

Fig 1: Checking Harness and Connector (Auxiliary Battery - Oil Pump - Body Ground)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Standard Resistance:

Combined resistance (R1, R2 and R3) of each part in the wire harness is below 6 Ω.

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: GO TO NEXT STEP

INSPECT HYBRID VEHICLE CONTROL ECU

Connect the intelligent tester to the DLC3.
Turn the ignition switch to the ON position.
Select the following menu items: DIAGNOSIS / OBD/ MOBD / HV ECU / ACTIVE TEST / INSPECTION MODE.
Put the vehicle into the READY on state.

Check the waveform between the terminals of the HV control ECU.

HYBRID VEHICLE CONTROL ECU

Tester Connection	Specified Condition
OPST (H34-7) - E1 (H31-5)	The waveform appears as shown in Fig 2.

Fig 2: Inspecting Hybrid Vehicle Control ECU

NG: REPLACE HYBRID VEHICLE CONTROL ECU

OK: REPLACE OIL PUMP W/ MOTOR ASSEMBLY