DESCRIPTION
The rear blower motor with fan sub-assembly is operated by signals from the air conditioning amplifier assembly. Rear blower motor speed signals are transmitted in accordance with changes in the duty ratio.
WIRING DIAGRAM
CAUTION / NOTICE / HINT
NOTICE:
Inspect the fuses for circuits related to this system before performing the following procedure.
PROCEDURE
1. | PERFORM ACTIVE TEST USING TECHSTREAM |
(a) Connect the Techstream to the DLC3.
(b) Turn the engine switch on (IG).
(c) Turn the Techstream on.
(d) Enter the following menus: Body Electrical / Air Conditioner / Active Test.
(e) Check the operation by referring to the table below.
Body Electrical > Air Conditioner > Active Test Tester Display | Measurement Item | Control Range | Diagnostic Note |
---|---|---|---|
Rear Blower Motor | Rear blower motor with fan sub-assembly | Min.: 0 Max.: 31 | - |
Tester Display |
---|
Rear Blower Motor |
OK | ![]() | PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE |
|
2. | CHECK HARNESS AND CONNECTOR (BLOWER MOTOR CONTROL - POWER SOURCE AND BODY GROUND) |
(a) Disconnect the R51 blower motor control connector.
(b) Measure the voltage and resistance according to the value(s) in the table below.
Standard Voltage:
Tester Connection | Condition | Specified Condition |
---|---|---|
R51-1 (+B) - Body ground | Always | 11 to 14 V |
Standard Resistance:
Tester Connection | Condition | Specified Condition |
---|---|---|
R51-6 (GND) - Body ground | Always | Below 1 Ω |
NG | ![]() | REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
3. | CHECK HARNESS AND CONNECTOR (BLOWER MOTOR CONTROL - AIR CONDITIONING AMPLIFIER ASSEMBLY) |
(a) Disconnect the J48 air conditioning amplifier assembly connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection | Condition | Specified Condition |
---|---|---|
R51-3 (SI) - J48-12 (BLWH) | Always | Below 1 Ω |
R51-3 (SI) or J48-12 (BLWH) - Other terminals and body ground | Always | 10 kΩ or higher |
NG | ![]() | REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
4. | CHECK HARNESS AND CONNECTOR (REAR BLOWER MOTOR WITH FAN SUB-ASSEMBLY - BLOWER MOTOR CONTROL AND BODY GROUND) |
(a) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection | Condition | Specified Condition |
---|---|---|
R50-2 (+) - R51-2 (VM) | Always | Below 1 Ω |
R50-1 (-) - Body ground | Always | Below 1 Ω |
R50-2 (+) or R51-2 (VM) - Other terminals and body ground | Always | 10 kΩ or higher |
NG | ![]() | REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
5. | INSPECT AIR CONDITIONING AMPLIFIER ASSEMBLY |
*a | Component with harness connected (Blower Motor Control) |
(a) Connect the J48 air conditioning amplifier assembly connector.
(b) Measure the waveform.
OK:
Waveform is similar to that shown in the illustration.
Item | Content |
---|---|
Terminal No. | R51-3 (SI) - Body ground |
Tool Setting | 2 V/DIV., 500 μs./DIV. |
Vehicle Condition |
|
HINT:
The waveform varies with the blower level.
NG | ![]() | REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY |
|
6. | INSPECT REAR BLOWER MOTOR WITH FAN SUB-ASSEMBLY |
(a) Remove the rear blower motor with fan sub-assembly connector.
Click here
(b) Inspect the rear blower motor with fan sub-assembly connector.
Click here
OK | ![]() | REPLACE BLOWER MOTOR CONTROL |
NG | ![]() | REPLACE REAR BLOWER MOTOR WITH FAN SUB-ASSEMBLY |
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