Toyota 4Runner: How To Proceed With Troubleshooting

Toyota 4Runner Service Manual / Vehicle Interior / Heating / Air Conditioning / Air Conditioning System(for Manual Air Conditioning System) / How To Proceed With Troubleshooting

CAUTION / NOTICE / HINT

HINT:

Use these procedures to troubleshoot the air conditioning system.
*: Use the Techstream.

PROCEDURE

1.	VEHICLE BROUGHT TO WORKSHOP

2.	CUSTOMER PROBLEM ANALYSIS AND SYMPTOM CHECK

3.	INSPECT BATTERY VOLTAGE

(a) Measure the voltage of the battery.

Standard voltage:

11 to 14 V

If the voltage is below 11 V, recharge or replace the battery before proceeding to the next step.

4.	CHECK COMMUNICATION FUNCTION OF CAN COMMUNICATION SYSTEM*

(a) Use the Techstream to check if the CAN communication system is functioning normally.

Result	Proceed to
CAN DTC is not output	A
CAN DTC is output	B

GO TO CAN COMMUNICATION SYSTEM

5.	CHECK FOR DTC*

(a) Check for DTCs and note any codes that are output (See page ).

(b) Clear the DTCs (See page ).

(c) Based on the DTCs output above, try to force output of the air conditioning system DTC by simulating the conditions indicated by the DTC. Then recheck for DTCs.

Result	Proceed to
DTC is not output	A
DTC is output	B

GO TO DIAGNOSTIC TROUBLE CODE CHART

6.	PROBLEM SYMPTOMS TABLE

(a) Refer to Problem Symptoms Table (See page
).

Result	Proceed to
Fault is not listed in problem symptoms table	A
Fault is listed in problem symptoms table	B

GO TO STEP 8

7.	OVERALL ANALYSIS AND TROUBLESHOOTING*

(a) Terminals of ECU (See page
).

(b) Data List / Active Test (See page ).

(d) Inspection

8.	ADJUST, REPAIR OR REPLACE

9.	CONFIRMATION TEST

END

System Diagram

SYSTEM DIAGRAM Communication Table Transmitter Receiver Signal Communication Line Air conditioning amplifier assembly ECM ...

Problem Symptoms Table

PROBLEM SYMPTOMS TABLE HINT: Use the table below to help determine the cause of problem symptoms. If multiple suspected areas are listed, the potential causes of the symptoms are lis ...

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