Toyota 4Runner: Air Conditioning Control Panel Circuit

Toyota 4Runner Service Manual / Vehicle Interior / Heating / Air Conditioning / Air Conditioning System(for Manual Air Conditioning System) / Air Conditioning Control Panel Circuit

DESCRIPTION

This circuit consists of the heater control assembly and air conditioning amplifier assembly. When the heater control assembly is operated, signals are transmitted to the air conditioning amplifier assembly through the LIN communication system.

If the LIN communication system malfunctions, the air conditioning amplifier assembly does not operate when the heater control assembly is operated.

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

Inspect the fuses for circuits related to this system before performing the following inspection procedure.

PROCEDURE

1.	CHECK HARNESS AND CONNECTOR (HEATER CONTROL - AIR CONDITIONING AMPLIFIER)

(a) Disconnect the F42 amplifier connector.

(b) Disconnect the F29 control connector.

Standard Resistance:

Tester Connection	Condition	Specified Condition
F29-10 (LIN1) - F42-37 (LIN1)	Always	Below 1 Ω
F29-10 (LIN1) - Body ground	Always	10 kΩ or higher

REPAIR OR REPLACE HARNESS OR CONNECTOR

2.	CHECK HARNESS AND CONNECTOR (HEATER CONTROL - BATTERY AND BODY GROUND)

(a) Disconnect the F29 control connector.

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

Standard Voltage:

Tester Connection	Switch Condition	Specified Condition
F29-4 (IG+) - F29-11 (GND)	Ignition switch off	Below 1 V
F29-4 (IG+) - F29-11 (GND)	Ignition switch ON	11 to 14 V

Standard Resistance:

Tester Connection	Condition	Specified Condition
F29-11 (GND) - Body ground	Always	Below 1 Ω

Text in Illustration

*a	Front view of wire harness connector (to Heater Control Assembly)

REPAIR OR REPLACE HARNESS OR CONNECTOR

3.	REPLACE HEATER CONTROL ASSEMBLY

(a) Replace the heater control assembly with a new or normally functioning one (See page ).

(b) Operate the heater control assembly to check that it functions properly.

OK:

Heater control assembly operates normally.

END (HEATER CONTROL ASSEMBLY IS FAULTY)

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

Air Mix Damper Control Servo Motor Circuit (Passenger Side) (B1441)

DESCRIPTION The damper servo sub-assembly (air mix damper servo) sends pulse signals to inform the No. 1 air conditioning amplifier assembly of the damper position. The No. 1 air conditioning amp ...

Air Conditioning Compressor Magnetic Clutch Circuit

DESCRIPTION When the air conditioning amplifier assembly is turned on, a magnet clutch assembly ON signal is sent from the MGC terminal of the air conditioning amplifier assembly. Then, the A/C C ...

Other materials about Toyota 4Runner:

Removal
REMOVAL PROCEDURE 1. REMOVE FRONT WHEEL 2. REMOVE FRONT FENDER MUDGUARD LH (w/o Intuitive Parking Assist System) 3. REMOVE ROCKER PANEL MOULDING COVER LH (w/o Intuitive Parking Assist System) 4. REMOVE FRONT FENDER MOULDING SUB-ASSEMBLY LH (w/o Intu ...

Shift Solenoid "B" Control Circuit Low (Shift Solenoid Valve S2) (P0976,P0977)
DESCRIPTION Shifting from 1st to 5th is performed in combination with the ON and OFF operation of the shift solenoid valves SL1, SL2, S1, S2 and SR, which is controlled by the ECM. If an open or short circuit occurs in one of the shift solenoid valves, th ...