DTC P0A1B-94: Drive Motor "A" Control Module Performance Unexpected Operation [09/2022 - ]: Procedure

1. Check the connection of the negative (-) and positive (+) auxiliary battery terminals.

   OK

   The terminals are connected securely and there is no contact problem.

   HINT: 

   If performing a reproduction test, turn the ignition switch to ON and shake the wire harnesses vertically and horizontally before checking for DTCs.

   Result

   Proceed to
   OK
   NG

Result: 

NG 

See step  7

Result: 

OK 

See step  2

1. Check the installation condition of the ground wires fD.

   OK

   The ground wires fD are securely installed.

   HINT: 

   If performing a reproduction test, turn the ignition switch to ON and shake the wire harnesses vertically and horizontally before checking for DTCs.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   Result

   Proceed to
   OK
   NG

Result: 

NG 

See step  8

Result: 

OK 

See step  3

Pre-procedure1

• Disconnect the cable from the negative (-) auxiliary battery terminal.
• Disconnect the cable from the positive (+) auxiliary battery terminal.

• Check the fusible link block assembly (BATT-MAIN NO. 1) for improper installation.

  OK

  The fusible link block assembly is installed securely and there is no contact problem.

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

  Standard Resistance

  Tester Connection	Condition	Specified Condition	Result
  A82-1 - A-1 (Positive (+) auxiliary battery terminal)	Ignition switch off	Below 1 Ω	Ω

  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

  *1	Fusible Link Block Assembly

  Result

  Proceed to
  OK
  NG

Post-procedure1

• Reconnect the cable from the positive (+) auxiliary battery terminal.
• Reconnect the cable from the negative (-) auxiliary battery terminal.

Result: 

NG 

See step  9

Result: 

OK 

See step  4

1. Check the IGCT-MAIN fuse for improper installation.

   OK

   The fuse is installed securely.

   HINT: 

   If performing a reproduction test, turn the ignition switch to ON and gently vibrate the IGCT-MAIN fuse with a finger before checking for DTCs.

2. Remove the IGCT-MAIN fuse from the No. 1 engine room relay block and junction block assembly.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition	Result
   IGCT-MAIN fuse	Ignition switch off	Below 1 Ω	Ω

4. Install the IGCT-MAIN fuse.

   Result

   Proceed to
   OK
   NG

Result: 

NG 

See step  10

Result: 

OK 

See step  5

1. Check the IGCT relay for improper installation.

   OK

   The relay is installed securely.

   HINT: 

   If performing a reproduction test, turn the ignition switch to ON and gently vibrate the IGCT relay with a finger before checking for DTCs.

2. Remove the IGCT relay from the No. 1 engine room relay block and junction block assembly.
3. Measure the resistance according to the value(s) in the table below.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   *1	IGCT Relay

   Standard Resistance

   Tester Connection	Condition	Specified Condition	Result
   3 - 5	Auxiliary battery voltage not applied between terminals 1 and 2	10 kΩ or higher	kΩ
   3 - 5	Auxiliary battery voltage applied between terminals 1 and 2	Below 1 Ω	Ω

4. Install the IGCT relay.

   Result

   Proceed to
   OK
   NG

Result: 

NG 

See step  11

Result: 

OK 

See step  6

Pre-procedure1

• None

• Check for DTCs.

  HINT: 

  Check the DTCs that were output when the vehicle was brought to the workshop.

  Powertrain > Engine > Trouble Codes 

  Powertrain > Hybrid Control > Trouble Codes 

  Result

  Result	Proceed to
  P0A1B-94 only is output.	A
  DTCs except P0A1B-94 are output for SFI system.	B
  Hybrid Control System DTC is output.	C

Post-procedure1

• Turn the ignition switch off.

Result: 

A 

REPLACE HYBRID MOTOR CONTROL INVERTER ASSEMBLY 

Refer to REMOVAL [09/2022 - ]

Result: 

B 

GO TO DTC CHART (SFI SYSTEM). Refer to  DIAGNOSTIC TROUBLE CODE CHART [09/2022 - 09/2024]  , or Refer to  DIAGNOSTIC TROUBLE CODE CHART [09/2024 - ] 

Result: 

C 

GO TO DTC CHART (HYBRID CONTROL SYSTEM) 

Refer to DIAGNOSTIC TROUBLE CODE CHART [09/2022 - ]

Result

Result: 

NEXT 

See step  12

Result

Result: 

NEXT 

See step  12

Result

Result: 

NEXT 

See step  12

Result

Result: 

NEXT 

See step  12

Result

Result: 

NEXT 

See step  12

Pre-procedure1

• None

• Read and record the DTCs and Freeze Frame Data.

  Powertrain > Engine > Trouble Codes 

• Clear the DTCs and Freeze Frame Data.

  Powertrain > Engine > Clear DTCs 

  Result

  Proceed to
  NEXT

Post-procedure1

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

Result: 

NEXT 

See step  13

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

   Result

   Proceed to
   NEXT

Result: 

NEXT 

See step  14

Pre-procedure1

• None

• Check for DTCs.

  Powertrain > Engine > Trouble Codes 

  Powertrain > Hybrid Control > Trouble Codes 

  Result

  Result	Proceed to
  No DTCs are output.	A
  P0A1B-94 only is output.	B
  DTCs except P0A1B-94 are output for SFI System.	C
  Hybrid Control System DTC is output.	D

Post-procedure1

• Turn the ignition switch off.

Result: 

A 

END 

Result: 

B 

REPLACE HYBRID MOTOR CONTROL INVERTER ASSEMBLY 

Refer to REMOVAL [09/2022 - ]

Result: 

C 

GO TO DTC CHART (SFI SYSTEM). Refer to  DIAGNOSTIC TROUBLE CODE CHART [09/2022 - 09/2024]  , or Refer to  DIAGNOSTIC TROUBLE CODE CHART [09/2024 - ] 

Result: 

D 

GO TO DTC CHART (HYBRID CONTROL SYSTEM) 

Refer to DIAGNOSTIC TROUBLE CODE CHART [09/2022 - ]