P0A4B-253

DESCRIPTION

A resolver is a sensor that detects the position of the magnetic poles, which are indispensable for ensuring highly efficient control of the Motor and Generator.
The resolver structure and method of connection with the MG ECU are the same as those of the motor resolver.
The MG ECU monitors output signals from the resolver and detects a malfunction.

DTC No.	INF Code	DTC Detection Condition	Trouble Area
P0A4B	253	Interphase short in generator resolver circuit	Wire harness or connector HV transaxle assembly (Generator resolver) w/ converter inverter assembly (MG ECU)
P0A4C	513	Generator resolver output is out of normal range	Wire harness or connector HV transaxle assembly (Generator resolver) w/ converter inverter assembly (MG ECU)
P0A4D	255	Open or short in generator resolver circuit	Wire harness or connector HV transaxle assembly (Generator resolver) w/ converter inverter assembly (MG ECU)

MONITOR DESCRIPTION

The MG ECU monitors the generator resolver output signal. If the MG ECU detects output signals that are out of the normal range or specification, it will conclude that there is a malfunction of the generator resolver. The HV control ECU will illuminate the MIL and set a DTC.

WIRING DIAGRAM

INSPECTION PROCEDURE

CAUTION:

1. 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.
   
2. After disconnecting the service plug grip, wait for at least 5 minutes before touching any of the high-voltage connectors or terminals.
   

NOTICE:

Check the output DTCs again after the repair has been completed. If P0A78-286, P0A7A-324, or P0A79-696 is output, replace the w/ converter inverter assembly.

HINT:

1. If the problem symptom cannot be reproduced, performing the driving test on a road on which the vehicle tends to vibrate will make it easier to reproduce the symptom.
   
2. If INF code 253 is output, an interphase short in the resolver circuit may have occurred due to water in the resolver. Thus, if the malfunction is not reproduced, it must be the HV transaxle assembly to replace at the last step.
   
3. At least 5 minutes is required to discharge the high-voltage capacitor inside the w/ converter inverter assembly.
   

1. CHECK CONNECTION CONDITION OF MG ECU CONNECTOR (LOOSENESS AND POOR CONTACT)

CAUTION:

Be sure to wear insulated gloves.

1. Turn the ignition switch off and remove the service plug grip. (Click here)

   NOTICE:

   Do not put the vehicle into the READY-on state with the service plug grip removed as this may cause a malfunction.

2. Remove the inverter cover. (Click here)

   NOTICE:

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

3. Check the connections of the MG ECU connectors.

   OK:

   Connectors are connected securely and there is no poor connection.
   

NG	CONNECT SECURELY

OK

2. INSPECT GENERATOR RESOLVER

NOTICE:

Be sure to wear insulated gloves.

1. Disconnect the I24 connector from the MG ECU.

2. Measure the voltage according to the value(s) in the table below when the ignition switch is in the ON position.

   Standard Voltage:

   Tester Connection	Specified Condition
   GRF (I24-12) - Body ground	Below 1 V
   GRFG (I24-22) - Body ground	Below 1 V
   GSN (I24-11) - Body ground	Below 1 V
   GSNG (I24-10) - Body ground	Below 1 V
   GCS (I24-9) - Body ground	Below 1 V
   GCSG (I24-8) - Body ground	Below 1 V

   NOTICE:

   Turning the ignition switch to the ON position with the MG ECU connectors disconnected causes other DTCs to be stored. Clear the DTCs after performing the inspection.

3. Turn the ignition switch off.

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

   Standard Resistance (Check for open):

   Tester Connection	Specified Condition
   GRF (I24-12) - GRFG (I24-22)	7.65 to 10.2 Ω
   GSN (I24-11) - GSNG (I24-10)	12.6 to 16.8 Ω
   GCS (I24-9) - GCSG (I24-8)	12.6 to 16.8 Ω

   Standard Resistance (Check for short):

   Tester Connection	Specified Condition
   GRF (I24-12) or GRFG (I24-22) - Body ground	10 kΩ or higher
   GSN (I24-11) or GSNG (I24-10) - Body ground	10 kΩ or higher
   GCS (I24-9) or GCSG (I24-8) - Body ground	10 kΩ or higher

OK	REPLACE W/ CONVERTER INVERTER ASSEMBLY

NG

3. CHECK CONNECTION CONDITION OF GENERATOR RESOLVER CONNECTOR (LOOSENESS AND POOR CONTACT)

1. Remove the w/ converter inverter assembly. (Click here)

2. Check the connection of the generator resolver connector.

   OK:

   Connector is connected securely and there is no poor connection.
   

NG	CONNECT SECURELY

OK

4. INSPECT GENERATOR RESOLVER

1. Disconnect the M6 generator resolver connector.

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

   Standard Resistance:

   Tester Connection	Specified Condition
   GRF (M6-1) - GRFG (M6-6)	7.65 to 10.2 Ω
   GSN (M6-2) - GSNG (M6-7)	12.6 to 16.8 Ω
   GCS (M6-3) - GCSG (M6-8)	12.6 to 16.8 Ω

3. Using a megohmmeter, measure the insulation resistance according to the value(s) in the table below.

   Standard Resistance:

   Tester Connection	Specified Condition
   GRF (M6-1) - GSN (M6-2)	10 MΩ or higher
   GRF (M6-1) - GCS (M6-3)	10 MΩ or higher
   GSN (M6-2) - GCS (M6-3)	10 MΩ or higher
   GRFG (M6-6) - GSNG (M6-7)	10 MΩ or higher
   GRFG (M6-6) - GCSG (M6-8)	10 MΩ or higher
   GSNG (M6-7) - GCSG (M6-8)	10 MΩ or higher
   Each terminal listed above - Transaxle housing	10 MΩ or higher

NG	REPLACE HYBRID VEHICLE TRANSAXLE ASSEMBLY

OK
REPAIR OR REPLACE HARNESS OR CONNECTOR