Lexus NX: Blower Motor Circuit
DESCRIPTION
The blower with fan motor sub-assembly is operated by signals from the air conditioning amplifier assembly. 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.
-
When the auxiliary battery is disconnected or the air conditioning amplifier assembly is replaced, be sure to perform servo motor initialization.
Click here
.gif)
PROCEDURE
| 1. | PERFORM ACTIVE TEST USING TECHSTREAM |
(a) Connect the Techstream to the DLC3.
(b) Turn the power 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 |
|---|---|---|---|
| Blower Motor | Blower with fan motor sub-assembly | Min.: 0 Max.: 31 | - |
| Tester Display |
|---|
| Blower Motor |
OK:
Blower with fan motor sub-assembly operates and changes speed.
| OK | .gif) | PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE |
|
.gif)
| 2. | CHECK HARNESS AND CONNECTOR (BLOWER WITH FAN MOTOR SUB-ASSEMBLY - AIR CONDITIONING AMPLIFIER ASSEMBLY, BATTERY AND BODY GROUND) |
(a) Disconnect the I50 air conditioning amplifier assembly connector.
(b) Disconnect the I28 blower with fan motor sub-assembly connector.
(c) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
| Tester Connection | Switch Condition | Specified Condition |
|---|---|---|
| I28-3 (+B) - Body ground | Power switch off | 11 to 14 V |
(d) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
| Tester Connection | Condition | Specified Condition |
|---|---|---|
| I28-1 (GND) - Body ground | Always | Below 1 Ω |
| I50-22 (BLW) - I28-2 (SI) | Always | Below 1 Ω |
| I50-22 (BLW) or I28-2 (SI) - Body ground | Always | 10 kΩ or higher |
| NG | | REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
| 3. | CHECK BLOWER WITH FAN MOTOR SUB-ASSEMBLY |
| (a) Disconnect the air conditioning amplifier assembly connector. |
|
(b) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
| Tester Connection | Switch Condition | Specified Condition |
|---|---|---|
| I50-22 (BLW) - Body ground | Power switch off | 4.5 to 5.5 V |
| NG | | REPLACE BLOWER WITH FAN MOTOR SUB-ASSEMBLY |
|
| 4. | CHECK AIR CONDITIONING AMPLIFIER ASSEMBLY |
| *a | Component with harness connected (Air Conditioning Amplifier Assembly) |
(a) Remove the air conditioning amplifier assembly with its connectors still connected.
Click here
(b) Turn the power switch on (IG).
(c) Turn the blower switch LO.
(d) Measure the waveform of the air conditioning amplifier assembly connector.
OK:
Waveform is similar to that shown in the illustration.
HINT:
The waveform varies with the blower speed.
| Item | Content |
|---|---|
| Tester Connection | I50-22 (BLW) - I50-14 (GND) |
| Tool setting | 1 V/DIV., 500 μs/DIV. |
| Vehicle condition | Power switch on (IG) Blower switch LO |
| OK | | REPLACE BLOWER WITH FAN MOTOR SUB-ASSEMBLY |
| NG | | REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY |
READ NEXT:
Heater Water Pump Circuit
DESCRIPTION The heater accessory assembly sends engine coolant to the heater core assembly while the engine is stopped to prevent heater effectiveness from becoming low. Directed by the air conditioni
PTC Heater Circuit
DESCRIPTION The air conditioning amplifier assembly sends operation signals to the PTC heater relays when quick heater assembly operation conditions are met. Based on the signals from the air conditio
Ambient Temperature Display System
DESCRIPTION The thermistor assembly (ambient temperature sensor) is installed in front of the cooler condenser assembly to detect the ambient temperature which is used to control the air conditioning
SEE MORE:
Lost Communication with Drive Motor Control Module "A" (U0110-160)
DESCRIPTION The MG ECU, which is built into in the inverter with converter assembly, controls motor (MG2) based on commands from the hybrid vehicle control ECU. The motor generator control ECU (MG ECU) monitors communication data and detects malfunctions. A communication error between the MG ECU and
EVAP System Tank Vapor Line Restricted/Blocked (P00FE)
DTC SUMMARY DTC No. Detection Item DTC Detection Condition Trouble Area MIL Memory P00FE EVAP System Tank Vapor Line Restricted/Blocked Leak detection pump creates negative pressure (vacuum) in EVAP system and EVAP system pressure is measured. When the fuel level in the fuel tan
