P0A09-591 - DC / DC Converter Status Circuit Low Input

L110F HYBRID VEHICLE CONTROL: HYBRID CONTROL SYSTEM: P0A09-591: DC / DC Converter Status Circuit Low Input
P0A09-591 - DC / DC Converter Status Circuit Low Input

DESCRIPTION

The hybrid vehicle converter (DC/DC converter) controls output voltage (12 V) based on duty ratio signals sent from the hybrid vehicle control ECU.

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 10 minutes before touching any of the high-voltage connectors or terminals. After waiting for 10 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 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:

B -- GO TO DTC CHART (P0AE6-225) P0AE6
A -- Continue to next step.

2. CHECK CONNECTOR CONNECTION CONDITION (HYBRID VEHICLE CONTROL ECU CONNECTOR)

(a) Check the connections of the hybrid vehicle control ECU connectors.

OK:

The connectors are connected securely and there are no contact problems.

NG -- CONNECT SECURELY
OK -- Continue to next step.

3. CHECK CONNECTOR CONNECTION CONDITION (NO. 2 BATTERY PACK WIRE CONNECTOR)

(a) Check the connection of the No. 2 battery pack wire connector.

OK:

The connector is connected securely and there are no contact problems.

HINT
For the removal and installation procedures related to inspection of the connection of the No. 2 battery pack wire connector, Removal.

NG -- CONNECT SECURELY
OK -- Continue to next step.

4. CHECK HYBRID VEHICLE CONTROL ECU (CHECK WAVEFORM)

(a) Connect an oscilloscope to the No. 2 battery pack wire connector terminals specified in the table below, and measure the waveform.

OK:

The waveform appears as shown in the illustration.

HINT
- Perform this inspection with the No. 2 battery pack wire connected.
- The waveform (duty) will vary depending on inspection conditions.

NG -- CHECK HARNESS AND CONNECTOR (RESISTANCE VALUE INSIDE HYBRID VEHICLE CONTROL ECU)
OK -- Continue to next step.

5. CLEAR DTC

(a) Select the following menu items: Powertrain / Hybrid Control / Trouble Codes.

(b) Read and record the DTCs and freeze frame data.

(c) Select the following menu items: Powertrain / Hybrid Control / Trouble Codes.

(d) Clear DTCs and freeze frame data.

NEXT -- Continue to next step.

6. 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:

B -- REPLACE HYBRID VEHICLE CONTROL ECU Components
A -- Continue to next step.

7. CHECK FOR INTERMITTENT PROBLEMS

(a) Check for intermittent problems Check For Intermittent Problems.

NG -- REPAIR OR REPLACE MALFUNCTIONING PARTS, COMPONENT AND AREA

OK -- REPLACE HYBRID VEHICLE CONTROL ECU Components

8. CHECK HARNESS AND CONNECTOR (RESISTANCE VALUE INSIDE HYBRID VEHICLE CONTROL ECU)

(a) Turn the power switch off.

(b) Disconnect the No. 2 battery pack wire connector.

Standard resistance:

NG -- CHECK HARNESS AND CONNECTOR (HYBRID VEHICLE CONTROL ECU - NO. 2 BATTERY PACK WIRE CONNECTOR)
OK -- Continue to next step.

9. CHECK CONNECTOR CONNECTION CONDITION (HYBRID VEHICLE CONVERTER CONNECTOR)

CAUTION:
Be sure to wear insulated gloves.

(a) Turn the power switch off.

(b) Remove the service plug grip Hybrid Control System.

NOTICE:
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) Check the connection of the low voltage connector of the hybrid vehicle converter.

OK:

The connector is connected securely and there are no contact problems.

NG -- CONNECT SECURELY
OK -- Continue to next step.

10. CHECK HARNESS AND CONNECTOR (NO. 2 BATTERY PACK WIRE CONNECTOR - HYBRID VEHICLE CONVERTER)

CAUTION:
Be sure to wear insulated gloves.

(a) Check that the service plug grip is not installed.

(b) Disconnect the low voltage connector from the hybrid vehicle converter.

(c) 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 -- REPLACE HYBRID VEHICLE CONVERTER Components

11. CHECK HARNESS AND CONNECTOR (HYBRID VEHICLE CONTROL ECU - NO. 2 BATTERY PACK WIRE CONNECTOR)

(a) Disconnect connector A74 from the hybrid vehicle control ECU.

(b) 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 -- REPLACE HYBRID VEHICLE CONTROL ECU Components