HEATING / AIR CONDITIONING: AIR CONDITIONING SYSTEM: TERMINALS OF ECU; 2021 - 2024 MY Camry HV [10/2020

Last Modified: 11-20-2023	6.11:8.1.0	Doc ID: RM100000001R40J
Model Year Start: 2021	Model: Camry HV	Prod Date Range: [10/2020 - ]
Title: HEATING / AIR CONDITIONING: AIR CONDITIONING SYSTEM: TERMINALS OF ECU; 2021 - 2024 MY Camry HV [10/2020 - ]

TERMINALS OF ECU

CHECK AIR CONDITIONING AMPLIFIER ASSEMBLY

w/o Seat Heater

w/ Seat Heater

HINT:

Check from the rear of the connector while it is connected to the air conditioning amplifier assembly.
Make sure to wait at least 2 minutes after turning the ignition switch off before performing an ECU terminal inspection.

Terminal No. (Symbol)	Wiring Color	Terminal Description	Condition	Specified Condition
K54-1 (B) - K54-4 (GND)	LA-B - W-B	Power source (Back-up)	Power switch off	11 to 14 V
K54-2 (IG+) - K54-4 (GND)	LA-GR - W-B	Power source (IG)	Power switch on (IG)	11 to 14 V
K54-2 (IG+) - K54-4 (GND)	LA-GR - W-B	Power source (IG)	Power switch off	Below 1 V
K54-4 (GND) - Body ground	W-B - Body ground	Ground for main power supply	Always	Below 1 V
K54-6 (BLW) - K54-4 (GND)	LG - W-B	Blower motor speed control signal	Power switch on (IG) Blower switch: LO	Pulse generation (See waveform 1)
K54-11 (CANH) - K54-12 (CANL)	SB - W	CAN communication system	CAN communication is performed	Pulse generation
K54-14 (LIN1) - K54-4 (GND)	W - W-B	LIN communication signal	Power switch on (IG)	Pulse generation (See waveform 2)
K55-1 (SG-1) - Body ground	LG - Body ground	Ground for cooler (room temp. sensor) thermistor	Always	Below 1 V
K55-2 (SG-2) - Body ground	W - Body ground	Ground for thermistor assembly	Always	Below 1 V
K55-3 (SG-4) - Body ground	L - Body ground	Ground for air conditioner pressure sensor	Always	Below 1 V
K55-6 (S5-3) - K55-3 (SG-4)	GR - L	Power supply for air conditioner pressure sensor	Power switch on (IG)	4.75 to 5.25 V
K55-6 (S5-3) - K55-3 (SG-4)	GR - L	Power supply for air conditioner pressure sensor	Power switch off	Below 1 V
K55-13 (TAM) - K55-2 (SG-2)	R - W	Thermistor assembly signal	Power switch on (IG) Ambient temperature: 25°C (77°F)	1.05 to 1.45 V
K55-13 (TAM) - K55-2 (SG-2)	R - W	Thermistor assembly signal	Power switch on (IG) Ambient temperature: 40°C (104°F)	0.64 to 0.87 V
K55-14 (TR) - K55-1 (SG-1)	GR - LG	Cooler (room temp. sensor) thermistor signal	Power switch on (IG) Cabin temperature: 25°C (77°F)	1.05 to 1.45 V
K55-14 (TR) - K55-1 (SG-1)	GR - LG	Cooler (room temp. sensor) thermistor signal	Power switch on (IG) Cabin temperature: 40°C (104°F)	0.64 to 0.87 V
K55-20 (ECOS) - K54-4 (GND)	W - W-B	ECO switch assembly (Electric parking brake switch assembly) signal	Power switch on (IG) ECO switch assembly (Electric parking brake switch assembly): off	11 to 14 V
K55-20 (ECOS) - K54-4 (GND)	W - W-B		Power switch on (IG) ECO switch assembly (Electric parking brake switch assembly): On	Below 1 V
K55-24 (PRE) - K55-3 (SG-4)	W - L	Air conditioner pressure sensor signal	Power switch on (READY) Air conditioning system operating Refrigerant pressure: Abnormal pressure (more than 2812 kPaG (28.7 kgf/cm2, 408 psi))	4.61 V or higher
			Power switch on (READY) Air conditioning system operating Refrigerant pressure: Abnormal pressure (less than 196 kPaG (2.0 kgf/cm2, 28 psi))	Below 0.74 V
			Power switch on (READY) Air conditioning system operating Refrigerant pressure: Normal pressure (less than 2812 kPaG (28.7 kgf/cm2, 408 psi) and more than 196 kPaG (2.0 kgf/cm2, 28 psi))	0.74 to 4.61 V
z28-2 (BUS G) - Body ground	-	Ground for BUS IC	Always	Below 1 V
z28-3 (BUS) - z28-2 (BUS G)	-	BUS IC control signal	Power switch on (IG)	Pulse generation (See waveform 3)
z28-4 (B BUS) - z28-2 (BUS G)	-	Power supply for BUS IC	Power switch off	11 to 14 V
z28-5 (SG) - Body ground	GR - Body ground	Ground for No. 1 cooler thermistor	Always	Below 1 V
z28-6 (TE) - z28-5 (SG)	GR - GR	No. 1 cooler thermistor signal	Power switch on (IG) Evaporator temperature: 0°C (32°F)	1.7 to 2.1 V
z28-6 (TE) - z28-5 (SG)	GR - GR	No. 1 cooler thermistor signal	Power switch on (IG) Evaporator temperature: 15°C (59°F)	0.9 to 1.3 V

(a) Waveform 1:

Item	Content
Terminal No.	K54-6 (BLW) - K54-4 (GND)
Tool Setting	2 V/DIV., 1 ms./DIV.
Condition	Power switch on (IG) Blower switch: LO

(b) Waveform 2:

Item	Content
Terminal No.	K54-14 (LIN1) - K54-4 (GND)
Tool Setting	2 V/DIV., 20 ms./DIV.
Condition	Power switch on (IG)

Item	Content
Terminal No.	z28-3 (BUS) - z28-2 (BUS G)
Tool Setting	2 V/DIV., 2 ms./DIV.
Condition	Power switch on (IG)

CHECK AIR CONDITIONING CONTROL ASSEMBLY

HINT:

Check from the rear of the connector while it is connected to the air conditioning control assembly.

Terminal No. (Symbol)	Wiring Color	Terminal Description	Condition	Specified Condition
K26-2 (IG+) - K26-6 (GND)	GR - W-B	Power source (IG)	Power switch off	Below 1 V
K26-2 (IG+) - K26-6 (GND)	GR - W-B	Power source (IG)	Power switch on (IG)	11 to 14 V
K26-6 (GND) - Body ground	W-B - Body ground	Ground for air conditioning control assembly	Always	Below 1 V
K26-9 (LIN1) - Body ground	LG - Body ground	LIN communication signal	Power switch on (IG)	Pulse generation
K26-11 (ILL+) - Body ground	W - Body ground	Illumination signal	Light control switch in off position	Below 1 V
K26-11 (ILL+) - Body ground	W - Body ground	Illumination signal	Light control switch in tail or head position	11 to 14 V
K26-15 (ILL-) - Body ground	B - Body ground	Illumination signal	Always	Below 1 V

(a) Waveform:

Item	Content
Terminal No.	K26-9 (LIN1) - Body ground
Tool Setting	2 V/DIV., 20 ms./DIV.
Condition	Power switch on (IG)

HYBRID VEHICLE CONTROL ECU ASSEMBLY

for Nickel Metal Hydride Battery: Click here

for Lithium-ion Battery: Click here