DTC P0A84-123: Hybrid Battery Pack Cooling Fan 1 Control Circuit Low: Procedure

WARNING: This page is about a different variant/trim than selected.

CHECK DTC OUTPUT (DTC P0AFC-123 IS OUTPUT) See step 1
B → See step 20

A: Go to next step

CHECK DTC OUTPUT

Connect the Techstream to the DLC3.
Turn the ignition switch to ON.
Enter the following menus: Powertrain / Hybrid Control / Trouble Codes.

Read output DTCs. Refer to DTC CHECK / CLEAR .

RESULT

Result	Proceed to
P0A84-123 is output	A
P0A84-123, P0A99-123, and P0AD2-123 are output	B

B → See step 9

A: Go to next step

CHECK BATTERY COOLING BLOWER ASSEMBLY (NO. 0) See step 2
B → See step 19

A: Go to next step

CHECK HARNESS AND CONNECTOR (BATT FAN RELAY - BATTERY COOLING BLOWER ASSEMBLY [NO. 0])

WARNING:

Be sure to wear insulated gloves and protective goggles.

Disconnect the cable from the negative (-) battery terminal.
Check that the service plug grip is not installed.
NOTE:
After removing the service plug grip, do not turn the ignition switch ON (READY), unless instructed by the repair information because this may cause a malfunction.
Remove the battery cover. Refer to REMOVAL .
Disconnect the O45 connector from the battery cooling blower assembly (No. 0).

Fig 1: Identifying Battery Cooling Blower Assembly & O45 Connector
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Remove the BATT FAN relay.

Fig 2: Identifying Fuse (BATT FAN)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

TEXT IN ILLUSTRATION

*1	Engine Room No. 3 Relay Block
*2	BATT FAN Relay

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

Fig 3: Measuring Resistance In BATT Fan Relay & O45 Connector

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Standard Resistance

Tester Connection	Switch Condition	Specified Condition
BATT FAN relay terminal 5 - O45-1 (IG0)	Ignition switch off	Below 1 Ω

TEXT IN ILLUSTRATION

*1	Engine Room No. 3 Relay Block
*2	Front view of wire harness connector (to Battery Cooling Blower Assembly [No. 0])
*3	BATT FAN Relay Holder

NOTE:

When taking a measurement with a tester, do not apply excessive force to the tester probe to avoid damaging the holder.

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: Go to next step

CHECK HARNESS AND CONNECTOR (BATTERY COOLING BLOWER ASSEMBLY [NO. 0] - BATTERY SMART UNIT)

WARNING:

Be sure to wear insulated gloves and protective goggles.

Disconnect the cable from the negative (-) battery terminal.
Check that the service plug grip is not installed.
NOTE:
After removing the service plug grip, do not turn the ignition switch ON (READY), unless instructed by the repair information because this may cause a malfunction.
Remove the battery cover. Refer to REMOVAL .
Disconnect the O45 connector from the battery cooling blower assembly (No. 0).

Fig 4: Identifying Battery Cooling Blower Assembly & O45 Connector
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Disconnect the z21 connector from the battery smart unit.

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

Fig 5: Measuring Resistance In Battery Smart Unit

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Standard Resistance (Check for Open)

Tester Connection	Switch Condition	Specified Condition
z21-8 (VM0) - O45-2 (VM0)	Ignition switch off	Below 1 Ω

Standard Resistance (Check for Short)

Tester Connection	Switch Condition	Specified Condition
O45-2 (VM0) or z21-8 (VM0) - Body ground	Ignition switch off	10 kΩ or higher

TEXT IN ILLUSTRATION

*1	Rear view of wire harness connector (to Battery Smart Unit)
*2	Front view of wire harness connector (to Battery Cooling Blower Assembly [No. 0])

NG → See step 25

OK: Go to next step

CHECK HARNESS AND CONNECTOR (BATTERY COOLING BLOWER ASSEMBLY [NO. 0] - BODY GROUND)

WARNING:

Be sure to wear insulated gloves and protective goggles.

Disconnect the cable from the negative (-) battery terminal.
Check that the service plug grip is not installed.
NOTE:
After removing the service plug grip, do not turn the ignition switch ON (READY), unless instructed by the repair information because this may cause a malfunction.
Remove the battery cover. Refer to REMOVAL .
Disconnect the O45 connector from the battery cooling blower assembly (No. 0).

Fig 6: Identifying Battery Cooling Blower Assembly & O45 Connector
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

Fig 7: Measuring Resistance In Blower Assembly

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Standard Resistance

Tester Connection	Switch Condition	Specified Condition
O45-4 (GND0) - Body ground	Ignition switch off	Below 1 Ω

TEXT IN ILLUSTRATION

*1	Front view of wire harness connector (to Battery Cooling Blower Assembly [No. 0])

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: Go to next step

CHECK HARNESS AND CONNECTOR (HYBRID VEHICLE CONTROL ECU - BATTERY COOLING BLOWER ASSEMBLY [NO. 0])

WARNING:

Be sure to wear insulated gloves and protective goggles.

Disconnect the cable from the negative (-) battery terminal.
Check that the service plug grip is not installed.
NOTE:
After removing the service plug grip, do not turn the ignition switch ON, unless instructed by the repair information because this may cause a malfunction.
Remove the battery cover. Refer to REMOVAL .
Disconnect the O45 connector from the battery cooling blower assembly (No. 0).

Fig 8: Identifying Battery Cooling Blower Assembly & O45 Connector
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Disconnect the A65 connector from the hybrid vehicle control ECU. Refer to REMOVAL .

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

Fig 9: Measuring Resistance In Hybrid Vehicle Control ECU

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Standard Resistance (Check for Open)

Tester Connection	Switch Condition	Specified Condition
O45-3 (SI0) - A65-29 (SI0)	Ignition switch off	Below 1 Ω

Standard Resistance (Check for Short)

Tester Connection	Switch Condition	Specified Condition
O45-3 (SI0) or A65-29 (SI0) - Body ground	Ignition switch off	10 kΩ or higher

TEXT IN ILLUSTRATION

*1	Rear view of wire harness connector (to Hybrid Vehicle Control ECU)
*2	Front view of wire harness connector (to Battery Cooling Blower Assembly [No. 0])

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: Go to next step

CHECK HYBRID VEHICLE CONTROL ECU

Using an oscilloscope, measure the waveform according to the condition in the table below.

Fig 10: Checking Hybrid Vehicle Control ECU With Waveform Reference

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Item	Contents
Terminal	A65-29 (SI0) - D72-6 (E1)
Equipment Setting	1 V/DIV, 50 μs/DIV
Condition	Ignition switch ON or ON (READY)

The waveform in the illustration can be measured.

HINT:

A and B in the DUTY waveform shown in the illustration vary depending on the cooling fan mode.
Duty command value is influenced by variance in fan motors and the change of power supply voltage.
Measure when the vehicle comes to a stop and an idling stop.

TEXT IN ILLUSTRATION

*1	Component with harness connected (Hybrid Vehicle Control ECU)

NG → See step 21

OK → See step 22

INSPECT FUSE (BATT FAN)

Remove the BATT FAN fuse.

Fig 11: Identifying Fuse (BATT FAN)
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

Standard Resistance

Tester Connection	Condition	Specified Condition
BATT FAN fuse	Always	Below 1 Ω

TEXT IN ILLUSTRATION

*1	Engine Room No. 3 Relay Block
*2	BATT FAN Fuse

NG → See step 16

OK: Go to next step

INSPECT RELAY (BATT FAN)

Remove the BATT FAN relay.

Fig 12: Identifying Fuse (BATT FAN)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

TEXT IN ILLUSTRATION

*1	Engine Room No. 3 Relay Block
*2	BATT FAN Relay

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

Fig 13: Identifying BATT FAN Relay

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Standard Resistance

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

NG → REPLACE RELAY (BATT FAN)

OK: Go to next step

CHECK HARNESS AND CONNECTOR (BATT FAN RELAY - BATT FAN FUSE)

Remove the BATT FAN relay.

Fig 14: Identifying Fuse (BATT FAN)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

TEXT IN ILLUSTRATION

*1	Engine Room No. 3 Relay Block
*2	BATT FAN Relay

Remove the BATT FAN fuse.

Fig 15: Identifying Fuse (BATT FAN)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

TEXT IN ILLUSTRATION

*1	Engine Room No. 3 Relay Block
*2	BATT FAN Fuse

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

Fig 16: Measuring Resistance In BATT Fan Fuse

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Standard Resistance

Tester Connection	Switch Condition	Specified Condition
BATT FAN fuse terminal 2 - BATT FAN relay terminal 1	Ignition switch off	Below 1 Ω
BATT FAN fuse terminal 2 - BATT FAN relay terminal 3	Ignition switch off	Below 1 Ω

TEXT IN ILLUSTRATION

*1	Engine Room No. 3 Relay Block
*2	BATT FAN Relay Holder
*3	BATT FAN Fuse Holder

NOTE:

When taking a measurement with a tester, do not apply excessive force to the tester probe to avoid damaging the holder.

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: Go to next step

CHECK HARNESS AND CONNECTOR (BATT FAN RELAY - BATTERY COOLING BLOWER ASSEMBLY [NO. 0])

WARNING:

Be sure to wear insulated gloves and protective goggles.

Disconnect the cable from the negative (-) battery terminal.
Check that the service plug grip is not installed.
NOTE:
After removing the service plug grip, do not turn the ignition switch ON (READY), unless instructed by the repair information because this may cause a malfunction.

Remove the BATT FAN relay.

Fig 17: Identifying Fuse (BATT FAN)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

TEXT IN ILLUSTRATION

*1	Engine Room No. 3 Relay Block
*2	BATT FAN Relay

Remove the battery cover. Refer to REMOVAL .
Disconnect the O45 connector from the battery cooling blower assembly (No. 0).

Fig 18: Identifying Battery Cooling Blower Assembly & O45 Connector
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

Fig 19: Measuring Resistance In BATT Fan Relay & O45 Connector

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Standard Resistance

Tester Connection	Switch Condition	Specified Condition
BATT FAN relay terminal 5 - O45-1 (IG0)	Ignition switch off	Below 1 Ω

TEXT IN ILLUSTRATION

*1	Engine Room No. 3 Relay Block
*2	Front view of wire harness connector (to Battery Cooling Blower Assembly [No. 0])
*3	BATT FAN Relay Holder

NOTE:

When taking a measurement with a tester, do not apply excessive force to the tester probe to avoid damaging the holder.

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: Go to next step

CHECK HARNESS AND CONNECTOR (BATT FAN RELAY - HYBRID VEHICLE CONTROL ECU)

Remove the BATT FAN relay.

Fig 20: Identifying Fuse (BATT FAN)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

TEXT IN ILLUSTRATION

*1	Engine Room No. 3 Relay Block
*2	BATT FAN Relay

Disconnect the A65 connector from the hybrid vehicle control ECU. Refer to REMOVAL .

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

Fig 21: Measuring Resistance In Hybrid Vehicle Control ECU

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Standard Resistance (Check for Open)

Tester Connection	Switch Condition	Specified Condition
BATT FAN relay terminal 2 - A65-4 (FCTL)	Ignition switch off	Below 1 Ω

Standard Resistance (Check for Short)

Tester Connection	Switch Condition	Specified Condition
BATT FAN relay terminal 2 or A65-4 (FCTL) - Body ground	Ignition switch off	10 kΩ or higher

TEXT IN ILLUSTRATION

*1	Engine Room No. 3 Relay Block
*2	Rear view of wire harness connector (to Hybrid Vehicle Control ECU)
*3	BATT FAN Relay Holder

NOTE:

When taking a measurement with a tester, do not apply excessive force to the tester probe to avoid damaging the holder.

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: Go to next step

CHECK HARNESS AND CONNECTOR (HYBRID VEHICLE CONTROL ECU - BODY GROUND)

Disconnect the D72 connector from the hybrid vehicle control ECU. Refer to REMOVAL .

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

Fig 22: Checking Harness And Connector (Hybrid Vehicle Control ECU - Body Ground)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Standard Resistance

Tester Connection	Switch Condition	Specified Condition
D72-5 (E01) - Body ground	Ignition switch off	Below 1 Ω

TEXT IN ILLUSTRATION

*1	Rear view of wire harness connector (to Hybrid Vehicle Control ECU)

NOTE:

When taking a measurement with a tester, do not apply excessive force to the tester probe to avoid damaging the holder.

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: Go to next step

CHECK HARNESS AND CONNECTOR (HYBRID VEHICLE CONTROL ECU - BODY GROUND)

Disconnect the D73 connector from the hybrid vehicle control ECU. Refer to REMOVAL .

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

Fig 23: Checking Harness And Connector (Hybrid Vehicle Control ECU - Body Ground)

Standard Resistance

Tester Connection	Switch Condition	Specified Condition
D73-5 (E02) - Body ground	Ignition switch off	Below 1 Ω

TEXT IN ILLUSTRATION

*1	Rear view of wire harness connector (to Hybrid Vehicle Control ECU)

NOTE:

When taking a measurement with a tester, do not apply excessive force to the tester probe to avoid damaging the holder.

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR

OK → See step 21

CHECK HARNESS AND CONNECTOR (BATT FAN RELAY - BODY GROUND)

Remove the BATT FAN relay.

Fig 24: Identifying Fuse (BATT FAN)

TEXT IN ILLUSTRATION

*1	Engine Room No. 3 Relay Block
*2	BATT FAN Relay

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

Fig 25: Measuring Resistance Of BATT FAN Relay

Standard Resistance

Tester Connection	Switch Condition	Specified Condition
BATT FAN relay terminal 3 - Body ground	Ignition switch off	10 kΩ or higher

TEXT IN ILLUSTRATION

*1	Engine Room No. 3 Relay Block
*2	BATT FAN Relay Holder

NOTE:

When taking a measurement with a tester, do not apply excessive force to the tester probe to avoid damaging the holder.

NG → See step 24

OK: Go to next step

CHECK HARNESS AND CONNECTOR (BATTERY COOLING BLOWER ASSEMBLY [NO. 0] - BODY GROUND)

WARNING:

Be sure to wear insulated gloves and protective goggles.

Disconnect the cable from the negative (-) battery terminal.
Check that the service plug grip is not installed.
NOTE:
After removing the service plug grip, do not turn the ignition switch ON (READY), unless instructed by the repair information because this may cause a malfunction.
Remove the battery cover. Refer to REMOVAL .
Disconnect each of the 3 battery cooling blower assembly connectors.

Fig 26: Identifying Battery Cooling Blower Assembly Connectors
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

Fig 27: Measuring Resistance In Cooling Blower Assembly

Standard Resistance

Tester Connection	Switch Condition	Specified Condition
O45-1 (IG0) - Body ground	Ignition switch off	10 kΩ or higher

TEXT IN ILLUSTRATION

*1	Front view of wire harness connector (to Battery Cooling Blower Assembly [No. 0])

NG → See step 24

OK: Go to next step

INSPECT BATTERY COOLING BLOWER ASSEMBLY

WARNING:

Be sure to wear insulated gloves and protective goggles.

Disconnect the cable from the negative (-) battery terminal.
Check that the service plug grip is not installed.
NOTE:
After removing the service plug grip, do not turn the ignition switch ON (READY), unless instructed by the repair information because this may cause a malfunction.
Remove the battery cover. Refer to REMOVAL .
Disconnect each of the 3 battery cooling blower assembly connectors.

Fig 28: Identifying Battery Cooling Blower Assembly Connectors
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

Fig 29: Measuring Resistance In Battery Cooling Blower Assembly

Standard Resistance

Tester Connection	Switch Condition	Specified Condition
A-1 (IG0) - Body ground	Ignition switch off	10 kΩ or higher
B-1 (IG2) - Body ground	Ignition switch off	10 kΩ or higher
C-1 (IG1) - Body ground	Ignition switch off	10 kΩ or higher

TEXT IN ILLUSTRATION

*1	Component without harness connected (Battery Cooling Blower Assembly)
*2	Battery Cooling Blower Assembly (No. 0)
*3	Battery Cooling Blower Assembly (No. 2)
*4	Battery Cooling Blower Assembly (No. 1)

NG → See step 23

OK → REPLACE FUSE (BATT FAN)

REPLACE BATTERY COOLING BLOWER ASSEMBLY (NO. 0). Refer to REMOVAL
GO TO DTC P0AFC-123. Refer to DTC P0AFC-123: Hybrid Battery Pack Sensor Module
REPLACE HYBRID VEHICLE CONTROL ECU. Refer to REMOVAL
REPLACE BATTERY SMART UNIT. Refer to REMOVAL
REPLACE BATTERY COOLING BLOWER ASSEMBLY (MALFUNCTIONING BATTERY COOLING BLOWER ASSEMBLY)
1. Replace the battery cooling blower assembly (malfunctioning battery cooling blower assembly). Refer to REMOVAL .
NEXT → REPLACE FUSE (BATT FAN)
REPAIR OR REPLACE HARNESS OR CONNECTOR
NEXT → REPLACE FUSE (BATT FAN)

CHECK HARNESS AND CONNECTOR (NO. 2 BATTERY PACK WIRE)

WARNING:

Be sure to wear insulated gloves and protective goggles.

Disconnect the cable from the negative (-) battery terminal.
Check that the service plug grip is not installed.
NOTE:
After removing the service plug grip, do not turn the ignition switch ON (READY), unless instructed by the repair information because this may cause a malfunction.
Remove the battery cover. Refer to REMOVAL .
Disconnect the Oz3 connector from the No. 2 battery pack wire.

Fig 30: Identifying OZ3 Connector And No. 2 Battery Pack Wire
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Disconnect the z21 connector from the battery smart unit.

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

Fig 31: Measuring Resistance Of Battery Smart Unit

Standard Resistance (Check for Open)

Tester Connection	Switch Condition	Specified Condition
z21-8 (VM0) - Oz3-12 (VM0)	Ignition switch off	Below 1 Ω

Standard Resistance (Check for Short)

Tester Connection	Switch Condition	Specified Condition
z21-8 (VM0) or Oz3-12 (VM0) - Body ground	Ignition switch off	10 kΩ or higher

TEXT IN ILLUSTRATION

*1	Rear view of wire harness connector (to Battery Smart Unit)
*2	Front view of wire harness connector (to No. 2 Battery Pack Wire Connector)

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR (NO. 2 BATTERY PACK WIRE)

OK → REPAIR OR REPLACE HARNESS OR CONNECTOR