Lexus NX: Fuel Injector Circuit
DESCRIPTION
The fuel injector assemblies are located on the intake port. They inject fuel into the cylinders based on the signals from the ECM.
WIRING DIAGRAM
CAUTION / NOTICE / HINT
NOTICE:
Inspect the fuses for circuits related to this system before performing the following procedure.
PROCEDURE
| 1. | CHECK TERMINAL VOLTAGE (POWER SOURCE OF FUEL INJECTOR ASSEMBLY) |
| *a | Front view of wire harness connector (to Fuel Injector Assembly) |
(a) Disconnect the fuel injector assembly connector.
(b) Turn the power switch on (IG).
(c) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
| Tester Connection | Condition | Specified Condition |
|---|---|---|
| C36-1 - Body ground | Power switch on (IG) | 11 to 14 V |
| C35-1 - Body ground | Power switch on (IG) | 11 to 14 V |
| G1-1 - Body ground | Power switch on (IG) | 11 to 14 V |
| G2-1 - Body ground | Power switch on (IG) | 11 to 14 V |
| NG | .gif) | GO TO STEP 4 |
|
.gif)
| 2. | INSPECT FUEL INJECTOR ASSEMBLY |
(a) Inspect the fuel injector assembly.
Click here .gif)
HINT:
Perform "Inspection After Repair" after replacing the fuel injector assembly.
Click here
| NG | | REPLACE FUEL INJECTOR ASSEMBLY |
|
| 3. | CHECK HARNESS AND CONNECTOR (FUEL INJECTOR ASSEMBLY - ECM) |
(a) Disconnect the fuel injector assembly connector.
(b) Disconnect the ECM connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
| Tester Connection | Condition | Specified Condition |
|---|---|---|
| C36-2 - C48-20 (#10) | Always | Below 1 Ω |
| C35-2 - C48-17 (#20) | Always | Below 1 Ω |
| G1-2 - C48-18 (#30) | Always | Below 1 Ω |
| G2-2 - C48-19 (#40) | Always | Below 1 Ω |
| C36-2 or C48-20 (#10) - Body ground | Always | 10 kΩ or higher |
| C35-2 or C48-17 (#20) - Body ground | Always | 10 kΩ or higher |
| G1-2 or C48-18 (#30) - Body ground | Always | 10 kΩ or higher |
| G2-2 or C48-19 (#40) - Body ground | Always | 10 kΩ or higher |
| OK | | PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE |
| NG | | REPAIR OR REPLACE HARNESS OR CONNECTOR |
| 4. | CHECK HARNESS AND CONNECTOR (IG2-MAIN RELAY - FUEL INJECTOR ASSEMBLY) |
(a) Remove the IG2-MAIN relay from the No. 1 engine room relay block and junction block assembly.
(b) Disconnect the fuel injector assembly connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
| Tester Connection | Condition | Specified Condition |
|---|---|---|
| 5 (IG2-MAIN relay) - C36-1 | Always | Below 1 Ω |
| 5 (IG2-MAIN relay) - C35-1 | Always | Below 1 Ω |
| 5 (IG2-MAIN relay) - G1-1 | Always | Below 1 Ω |
| 5 (IG2-MAIN relay) - G2-1 | Always | Below 1 Ω |
| 5 (IG2-MAIN relay) or C36-1 - Body ground | Always | 10 kΩ or higher |
| 5 (IG2-MAIN relay) or C35-1 - Body ground | Always | 10 kΩ or higher |
| 5 (IG2-MAIN relay) or G1-1 - Body ground | Always | 10 kΩ or higher |
| 5 (IG2-MAIN relay) or G2-1 - Body ground | Always | 10 kΩ or higher |
| OK | | GO TO ECM POWER SOURCE CIRCUIT |
| NG | | REPAIR OR REPLACE HARNESS OR CONNECTOR |
READ NEXT:
MIL Circuit
DESCRIPTION The Malfunction Indicator Lamp (MIL) is used to indicate vehicle malfunctions detected by the ECM. The MIL operation can be checked visually. When the power switch is turned on (IG), the M
Rough Idling
DESCRIPTION Problem Symptom Suspected Area Trouble Area
Engine speed fluctuation due to abnormal combustion
Idle speed too low or high
Strong engine vibration due to above symptoms
SEE MORE:
How To Proceed With Troubleshooting
CAUTION / NOTICE / HINT HINT:
Use the following procedure to troubleshoot the vehicle proximity notification system.
*: Use the GTS.
PROCEDURE 1. VEHICLE BROUGHT TO WORKSHOP
NEXT 2. CUSTOMER PROBLEM ANALYSIS AND SYMPTOM CHECK HINT:
In troubleshooting, co
System Description
SYSTEM DESCRIPTION OUTLINE (Lexus Enform Remote) (a) Lexus Enform Remote enables the user to check the vehicle status and operate the vehicle from a remote location. (b) Lexus Enform Remote is available by installing a dedicated smartphone application after entering a service contract*.
*: Lexus
