RM38T0EC _51 Engine / Hybrid System _144957 HYBRID / BATTERY CONTROL _0604233 MOTOR GENERATOR CONTROL SYSTEM C

HYBRID / BATTERY CONTROL  MOTOR GENERATOR CONTROL SYSTEM  P31241F  Lost Communication between Drive Motor "A" and HV/EV ECU Circuit Intermittent  


DESCRIPTION

The motor generator control ECU, which is built into the inverter with converter assembly, controls the motor (MG2) based on commands from the hybrid vehicle control ECU.

The motor generator control ECU (MG ECU) monitors communication data and detects malfunctions.

DTC No. Detection Item DTC Detection Condition Trouble Area MIL Warning Indicate Note
P31241F Lost Communication between Drive Motor "A" and HV/EV ECU Circuit Intermittent Error in reception from hybrid vehicle control ECU via serial communication (out of communication standard) detected when DTC P0C7917, P0E5717, P0D3319, P1C5D19 or P1C5F19 is stored.
(1 trip detection logic)
·

Inverter with converter assembly

·

Hybrid vehicle control ECU

·

Wire harness or connector


Does not come on Master Warning:
Does not come on 		SAE Code:
P3124

CONFIRMATION DRIVING PATTERN

HINT:

After repair has been completed, clear the DTC and then check that the vehicle has returned to normal by performing the following All Readiness check procedure.

Click hereEngine / Hybrid System>HYBRID / BATTERY CONTROL>MOTOR GENERATOR CONTROL SYSTEM>UTILITY


1.

Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).

2.

Turn the ignition switch off and wait for 2 minutes or more.

3.

Turn the ignition switch to ON and wait for 2 minutes or more.

4.

Enter the following menus: Powertrain / Motor Generator / Utility / All Readiness.

5.

Check the DTC judgment result.

HINT:
·

If the judgment result shows NORMAL, the system is normal.

·

If the judgment result shows ABNORMAL, the system has a malfunction.

·

If the judgment result shows INCOMPLETE, perform the normal judgment procedure again.




CAUTION / NOTICE / HINT

CAUTION:

Refer to the precautions before inspecting high voltage circuit.

Click hereEngine / Hybrid System>HYBRID / BATTERY CONTROL>MOTOR GENERATOR CONTROL SYSTEM>PRECAUTION


NOTICE:
·

After the ignition switch is turned off, there may be a waiting time before disconnecting the negative (-) auxiliary battery terminal.

Click hereGeneral>SETUP>WHEN DISCONNECTING OR RECONNECTING BATTERY TERMINAL>BEFORE DISCONNECTING BATTERY

·

When disconnecting and reconnecting the auxiliary battery.

HINT:

When disconnecting and reconnecting the auxiliary battery, there is an automatic learning function that completes learning when the respective system is used.

Click hereGeneral>SETUP>WHEN DISCONNECTING OR RECONNECTING BATTERY TERMINAL>AUTOMATIC LEARNING CHART




PROCEDURE

1.CLEAR DTC
a.

Clear the DTCs.

Powertrain > Motor Generator > Clear DTCs
50002 395

b.

Turn the ignition switch off.


Result:
Proceed to
NEXT



NEXT

2.CHECK DIAGNOSIS RELATED INFORMATION AND DTC OUTPUT (MOTOR GENERATOR)
2.CHECK DIAGNOSIS RELATED INFORMATION AND DTC OUTPUT (MOTOR GENERATOR)
a.

Turn the ignition switch to ON and wait for 2 minutes or more.


b.

Check for DTCs.

Powertrain > Motor Generator > Utility
Tester Display
Diagnosis Related Information
50005 395 56
Powertrain > Motor Generator > Trouble Codes
50001 395
Result:
Result Proceed to
P31241F is listed in Diagnosis Related Information or P31241F is output. A
P31241F are not listed in Diagnosis Information and P31241F is not output. B



c.

Turn the ignition switch off.



A

3.CHECK HYBRID VEHICLE CONTROL ECU (CHECK WAVEFORM)

B

CHECK FOR INTERMITTENT PROBLEMS

Click hereGeneral>INTRODUCTION>HOW TO TROUBLESHOOT ECU CONTROLLED SYSTEMS>HOW TO PROCEED WITH TROUBLESHOOTING


3.CHECK HYBRID VEHICLE CONTROL ECU (CHECK WAVEFORM)
a.

Connect an oscilloscope between the hybrid vehicle control ECU terminals specified in the following table.


b.

Turn the ignition switch to ON.


c.

Measure the waveform.

A499158C23
2.604,0.094 3.031,0.385 0.427,0.292 4.729,0.104 5.156,0.396 0.427,0.292 3.833,2.052 3.552,1.125 true 5.844,2.125 5.792,1.115 true 3.208,2.021 3.385,1.125 true 2.417,2.406 2.875,2.604 0.458,0.198 10 false CH1 2.438,3.021 2.896,3.219 0.458,0.198 10 false CH2 4.635,2.844 5.094,3.042 0.458,0.198 10 false GND 4.635,3.313 5.094,3.51 0.458,0.198 10 false GND 0.104,0.104 0.417,0.302 0.313,0.198 10 false *a 2.667,0.156 3.198,0.396 0.531,0.24 10 false A197 3.688,2.063 4.188,2.26 0.5,0.198 10 false HMCL 3.052,2.063 3.552,2.25 0.5,0.188 10 false HMCH 5.802,2.156 6.073,2.333 0.271,0.177 10 false E1 4.823,0.167 5.198,0.375 0.375,0.208 10 false I278
*a Component with harness connected
(Hybrid Vehicle Control ECU) 		- -


Item Contents
Tester Connection CH1: A197-2 (HMCH) - I278-1 (E1)
CH2: A197-1 (HMCL) - I278-1 (E1)
Equipment Setting 1 V/DIV., 200 μs./DIV.
Condition Ignition switch ON

Result:
Result Proceed to
The waveform appears as shown in the illustration. A
The waveform differs from the one shown in the illustration. B


HINT:
·

Perform this inspection with the connector connected.

·

If pulses are generated, the shape of the waveform can be assumed to be normal.

·

The shape of the waveform may vary according to communication conditions.




d.

Turn the ignition switch off.



A

REPLACE INVERTER WITH CONVERTER ASSEMBLY

Click hereEngine / Hybrid System>HYBRID / BATTERY CONTROL>INVERTER WITH CONVERTER>REMOVAL


B

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

Click hereEngine / Hybrid System>HYBRID / BATTERY CONTROL>HYBRID CONTROL SYSTEM>P056014

Result:
Proceed to
OK
NG



OK

5.CHECK CONNECTOR CONNECTION CONDITION (INVERTER WITH CONVERTER ASSEMBLY CONNECTOR)

NG

CONNECT SECURELY

5.CHECK CONNECTOR CONNECTION CONDITION (INVERTER WITH CONVERTER ASSEMBLY CONNECTOR)

Click hereEngine / Hybrid System>HYBRID / BATTERY CONTROL>MOTOR GENERATOR CONTROL SYSTEM>P033506

Result:
Result Proceed to
OK A
NG (The connector is not connected securely.) B
NG (The terminals are not making secure contact or are deformed, or water or foreign matter exists in the connector.) C



A

6.CHECK HARNESS AND CONNECTOR (HYBRID VEHICLE CONTROL ECU - INVERTER WITH CONVERTER ASSEMBLY)

B

CONNECT SECURELY

C

REPAIR OR REPLACE HARNESS OR CONNECTOR

6.CHECK HARNESS AND CONNECTOR (HYBRID VEHICLE CONTROL ECU - INVERTER WITH CONVERTER ASSEMBLY)
CAUTION:

Be sure to wear insulated gloves.


a.

Check that the service plug grip is not installed.

NOTICE:

After removing the service plug grip, do not turn the ignition switch to ON (READY), unless instructed by the repair manual because this may cause a malfunction.



b.

Disconnect the inverter with converter assembly connector.


c.

Disconnect the hybrid vehicle control ECU connector.


d.

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

Standard Resistance (Check for Open):
Tester Connection Condition Specified Condition
A192-29 (HMCH) - A197-2 (HMCH) Ignition switch off Below 1 Ω
A192-30 (HMCL) - A197-1 (HMCL) Ignition switch off Below 1 Ω


Standard Resistance (Check for Short):
Tester Connection Condition Specified Condition
A192-29 (HMCH) or A197-2 (HMCH) - Body ground and other terminals Ignition switch off 10 kΩ or higher
A192-30 (HMCL) or A197-1 (HMCL) - Body ground and other terminals Ignition switch off 10 kΩ or higher



e.

Connect the cable to the negative (-) auxiliary battery terminal.


f.

Turn the ignition switch to ON.


g.

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

Standard Voltage:
Tester Connection Condition Specified Condition
A192-29 (HMCH) or A197-2 (HMCH) - Body ground and other terminals Ignition switch ON Below 1 V
A192-30 (HMCL) or A197-1 (HMCL) - Body ground and other terminals Ignition switch ON Below 1 V


NOTICE:

Turning the ignition switch to ON with the hybrid vehicle control ECU and inverter with converter assembly connectors disconnected causes other DTCs to be stored. Clear the DTCs after performing this inspection.


HINT:

As there might be an intermittent malfunction, inspect the following items even if the measured resistance is as specified.

Check that each connector between the inverter with converter assembly and hybrid vehicle control ECU is not loose or disconnected.



h.

Turn the ignition switch off.


i.

Reconnect the hybrid vehicle control ECU connector.


j.

Reconnect the inverter with converter assembly connector.


Result:
Proceed to
OK
NG



OK

7.CHECK INVERTER WITH CONVERTER ASSEMBLY

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

7.CHECK INVERTER WITH CONVERTER ASSEMBLY
a.

Disconnect the hybrid vehicle control ECU connector.


b.

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

Standard Resistance:
Tester Connection Condition Specified Condition
A197-2 (HMCH) - A197-1 (HMCL) Ignition switch off 80 to 170 Ω



c.

Reconnect the hybrid vehicle control ECU connector.


Result:
Proceed to
OK
NG



OK

REPLACE HYBRID VEHICLE CONTROL ECU

Click hereEngine / Hybrid System>HYBRID / BATTERY CONTROL>HYBRID VEHICLE CONTROL ECU>REMOVAL


NG

REPLACE INVERTER WITH CONVERTER ASSEMBLY

Click hereEngine / Hybrid System>HYBRID / BATTERY CONTROL>INVERTER WITH CONVERTER>REMOVAL