Toyota 4Runner: 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 listed in order of probability in the "Suspected Area" column of the table. Check each symptom by checking the suspected areas in the order they are listed. Replace parts as necessary.
- Inspect the fuses and relays related to this system before inspecting the suspected areas below.
|
Symptom |
Suspected Area |
See page |
|---|---|---|
|
All functions of A/C system do not operate |
Proceed to "IG Power Source Circuit" |
|
|
Proceed to "Back-up Power Source Circuit" |
|
|
|
Proceed to "Air Conditioning Control Panel Circuit" |
|
|
|
Replace air conditioning amplifier assembly |
|
|
|
LIN communication system |
|
|
|
Air Flow Control: No blower operation |
Proceed to "Blower Motor Circuit" |
|
|
Proceed to "Air Conditioning Control Panel Circuit" |
|
|
|
Replace air conditioning amplifier assembly |
|
|
|
LIN communication system |
|
|
|
Air Flow Control: No blower control |
Proceed to "Blower Motor Circuit" |
|
|
Proceed to "Air Conditioning Control Panel Circuit" |
|
|
|
Replace air conditioning amplifier assembly |
|
|
|
LIN communication system |
|
|
|
Air Flow Control: Insufficient air flow |
Proceed to "Blower Motor Circuit" |
|
|
Replace air conditioning amplifier assembly |
|
|
|
Temperature Control: No cool air comes out |
Check volume of refrigerant |
|
|
Check for refrigerant gas leak |
|
|
|
Replace cooler expansion valve |
|
|
|
Check cooler compressor assembly |
|
|
|
Check No. 1 pressure switch |
|
|
|
Proceed to "Air Conditioning Compressor Magnetic Clutch Circuit" |
|
|
|
Proceed to "Compressor Lock Sensor Circuit" |
|
|
|
Proceed to "Air Mix Damper Control Servo Motor Circuit" |
|
|
|
Proceed to "Ambient Temperature Sensor Circuit" |
|
|
|
Proceed to "Evaporator Temperature Sensor Circuit" |
|
|
|
Proceed to "Communication Malfunction (Bus Ic)" |
|
|
|
Proceed to "Air Conditioning Control Panel Circuit" |
|
|
|
Replace air conditioning amplifier assembly |
|
|
|
LIN communication system |
|
|
|
Temperature Control: No warm air comes out |
Proceed to "Air Conditioning Control Panel Circuit" |
|
|
Proceed to "Air Mix Damper Control Servo Motor Circuit" |
|
|
|
Proceed to "Communication Malfunction (Bus Ic)" |
|
|
|
Replace air conditioning amplifier assembly |
|
|
|
LIN communication system |
|
|
|
Temperature Control: Output air is warmer or cooler than set temperature or response is slow |
Check volume of refrigerant |
|
|
Check for refrigerant gas leak |
|
|
|
Replace cooler expansion valve |
|
|
|
Check cooler compressor assembly |
|
|
|
Replace heater radiator unit sub-assembly |
|
|
|
Check No. 1 pressure switch |
|
|
|
Proceed to "Air Conditioning Compressor Magnetic Clutch Circuit" |
|
|
|
Proceed to "Compressor Lock Sensor Circuit" |
|
|
|
Proceed to "Air Mix Damper Control Servo Motor Circuit" |
|
|
|
Proceed to "Air Inlet Damper Control Servo Motor Circuit" |
|
|
|
Proceed to "Ambient Temperature Sensor Circuit" |
|
|
|
Proceed to "Evaporator Temperature Sensor Circuit" |
|
|
|
Proceed to "Communication Malfunction (Bus Ic)" |
|
|
|
Proceed to "Air Conditioning Control Panel Circuit" |
|
|
|
Replace air conditioning amplifier assembly |
|
|
|
LIN communication system |
|
|
|
No air inlet control |
Proceed to "Communication Malfunction (Bus Ic)" |
|
|
Proceed to "Air Inlet Damper Control Servo Motor Circuit" |
|
|
|
Replace air conditioning amplifier assembly |
|
|
|
No air flow mode control |
Proceed to "Communication Malfunction (Bus Ic)" |
|
|
Proceed to "Air Outlet Damper Control Servo Motor Circuit" |
|
|
|
Replace air conditioning amplifier assembly |
|
|
|
Engine coolant does not warm up quickly when the engine is cold (PTC heater does not operate)* |
Proceed to "PTC Heater Circuit" |
|
|
Proceed to "Generator Signal Circuit" |
|
|
|
Check generator assembly |
|
|
|
Replace air conditioning amplifier assembly |
|
|
|
Engine idle up does not occur or is continuous |
Replace air conditioning amplifier assembly |
|
|
Replace ECM |
|
|
|
CAN communication system |
|
|
|
Diagnostic trouble codes are not stored, and set mode is cleared when ignition switch is off |
Proceed to "Back-up Power Source Circuit" |
|
|
Replace air conditioning amplifier assembly |
|
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- *: w/ PTC Heater
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 W ...
Diagnosis System
DIAGNOSIS SYSTEM
1. DESCRIPTION
(a) Air conditioning system data and Diagnostic Trouble Codes (DTCs) can be read
through the Data Link Connector 3 (DLC3) of the vehicle. When the system seems to
...
Other materials about Toyota 4Runner:
Power Steering Warning Light Circuit
DESCRIPTION
The power steering ECU assembly is connected to the combination meter assembly
via CAN communication. If the power steering ECU assembly detects a malfunction,
the power steering warning light comes on. At this time, the vehicle enters fail-sa ...
TC and CG Terminal Circuit
DESCRIPTION
DTC output mode is set by connecting terminals 13 (TC) and 4 (CG) of the DLC3.
The DTCs are output by the blinking of the tire pressure warning light.
WIRING DIAGRAM
HINT:
When each warning light blinks continuously, a ground short in the w ...
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