Lexus RX (RX 350L, RX450h) 2016-2024 Repair Manual: Fuel Receiver Gauge Display Malfunction

DESCRIPTION

FUEL RECEIVER GAUGE OPERATION

(a) OPERATION

The combination meter assembly uses the fuel sender gauge assembly to detect the amount of fuel remaining in the fuel tank assembly. The Hall IC built into the fuel sender gauge assembly changes the output voltage according to the amount of fuel remaining. The combination meter assembly detects the voltage output from the fuel sender gauge assembly and operates the fuel receiver gauge.

FUEL RECEIVER GAUGE READING

(a) During normal driving:

As the fuel level in the fuel tank assembly changes when driving on a hill or applying the brakes, the fuel receiver gauge reading is updated according to the fuel injection volume during normal driving. However, as the fuel injection volume measurement has a margin of error, the value is indicated after correction by input values from the fuel sender gauge assembly.

(b) During refueling:

The fuel level in the fuel tank assembly rises rapidly when fuel is added. If the averaging process that is used during normal driving is used in this case, the fuel receiver gauge reading cannot be updated promptly. Therefore, when it is judged that fuel is being added to the vehicle based on the shift lever position and changes in the fuel level, output values from the fuel sender gauge assembly is immediately reflected in the fuel receiver gauge reading. This control is called refueling judgment.

NOTICE:

Add fuel with the engine switch off to ensure safety and to enable refueling judgment so that an appropriate fuel receiver gauge reading is obtained. If it is necessary to add fuel with the engine switch on (IG), move the shift lever to P or N.

REFUELING JUDGMENT CONDITIONS

(a) Normal judgment condition (When normal refueling method is used)

With the engine switch off, the fuel sender gauge assembly detects a change of 5.0 liters (5.3 US qts, 4.4 Imp. qts) or more in the fuel level.

(b) Other judgment conditions (When other refueling method is used)

Any of the following conditions is met:

PRECAUTION FOR REFUELING

The fuel sender gauge assembly cannot detect changes in the fuel level within certain ranges (around points E and F). Therefore, even if 5.0 liters (5.3 US qts, 4.4 Imp. qts) or more of fuel is added, refueling judgment may not be performed and the fuel receiver gauge reading may not change when fuel level is within such ranges.

FORCED RESET OF FUEL RECEIVER GAUGE

When driving at 1.8 km/h (1 mph) or more, if the output values from the fuel sender gauge assembly is different from the fuel receiver gauge reading by 15.0 liters (15.9 US qts, 13.2 Imp. qts) or more for approximately 2 minutes, output values from both gauge assemblies are immediately reflected in the fuel receiver gauge reading to compensate for a situation when refueling judgment cannot be made.

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

When replacing the combination meter assembly, always replace it with a new one. If a combination meter assembly which was installed to another vehicle is used, the information stored in it will not match the information from the vehicle and a DTC may be stored.

PROCEDURE

1.	CHECK SYMPTOMS

(a) Ask the customer about the problem symptoms.

Result	Proceed to
Malfunction occurs when adding fuel (Even after adding fuel, reading does not increase at all or increases very slowly, etc.)	A
Malfunction occurs during normal driving (The reading does not change, decreases quickly or decreases when the vehicle is not being driven, etc.) (The problem symptom recurs)	B
Malfunction occurs during normal driving (The reading does not change, decreases quickly or decreases when the vehicle is not being driven, etc.) (The problem symptom does not recur)	C

B

GO TO STEP 12

C

GO TO STEP 18

A

2.	CONFIRM MODEL

(a) Choose the model to be inspected.

Result	Proceed to
for Optitron Meter Type	A
for TFT Meter Type	B

B

GO TO STEP 4

A

3.	PERFORM ACTIVE TEST USING TECHSTREAM (FUEL METER OPERATION)

(a) Connect the Techstream to the DLC3.

(b) Turn the engine switch on (IG).

(c) Turn the Techstream on.

(d) Enter following menus: Body Electrical / Combination Meter / Active Test.

(e) Perform the Active Test according to the display on the Techstream.

Body Electrical > Combination Meter > Active Test

Tester Display	Measurement Item	Control Range	Diagnostic Note
Fuel Meter Operation	Fuel receiver gauge	OFF, Sender E, Empty, Warning, 1/4, 1/2, 3/4, Full, Sender F	-

Body Electrical > Combination Meter > Active Test

Tester Display
Fuel Meter Operation

OK:

Fuel receiver gauge indication is normal.

NG

REPLACE COMBINATION METER ASSEMBLY

OK

4.	CHECK FOR DTC

(a) Check if SFI system DTCs are output.

Click here

Powertrain > Engine > Trouble Codes

Result	Proceed to
SFI system DTCs are not output.	A
SFI system DTCs are output.	B

B

GO TO SFI SYSTEM

A

5.	CHECK FOR DTC

(a) Check if vehicle stability control system DTCs are output.

Click here

Chassis > Brake/EPB > Trouble Codes

Result	Proceed to
Vehicle stability control system DTCs are not output.	A
Vehicle stability control system DTCs are output.	B

B

GO TO VEHICLE STABILITY CONTROL SYSTEM

A

6.	CHECK FUEL RECEIVER GAUGE OPERATION BY ADDING FUEL

(a) Record the fuel receiver gauge reading.

(b) If the fuel tank assembly is almost full, drain 20 liters or more of fuel. (This is not necessary when the fuel tank assembly is sufficiently below full.)

(c) Disconnect the cable from the negative (-) battery terminal to reset the fuel receiver gauge.

HINT:

Check that the engine switch is turned off before disconnecting the cable from the negative (-) battery terminal.

(d) Connect the cable to the negative (-) battery terminal and turn the engine switch on (IG).

(e) Check that the fuel receiver gauge has been reset.

(f) Drive the vehicle at 1.75 km/h or more, then move the shift lever to P and turn the engine switch off.

(g) Add 5.0 liters or more of fuel, turn the engine switch on (IG), and check that the fuel receiver gauge reading increases in proportion to the amount of fuel added.

Result	Proceed to
Fuel receiver gauge reading increases in proportion to the amount of fuel added	A
Fuel receiver gauge reading does not change even when fuel is added	B

B

GO TO STEP 8

A

7.	INSPECT FUEL TANK ASSEMBLY

HINT:

Inspect the fuel tank assembly for deformation, foreign matter or an improperly installed fuel receiver gauge, as this may be the cause of the fuel receiver gauge malfunction.

(a) Visually check the fuel tank assembly for any abnormalities.

(b) Check if there is an excessive amount of foreign matter in the fuel tank assembly.

(c) Check the installation condition of the fuel tank assembly and fuel sender gauge assembly.

Result	Proceed to
Normal	A
Appearance of the fuel tank assembly is abnormal.	B
There is an excessive amount of foreign matter in the fuel tank assembly.	C
The fuel tank assembly or fuel sender gauge assembly is not installed correctly.	D

B

REPLACE FUEL TANK ASSEMBLY

C

CLEAN INSIDE OF FUEL TANK ASSEMBLY

D

INSTALL FUEL TANK ASSEMBLY OR FUEL SENDER GAUGE ASSEMBLY CORRECTLY

A

8.	READ VALUE USING TECHSTREAM (FUEL INPUT)

(a) Connect the Techstream to the DLC3.

(b) Turn the engine switch on (IG).

(c) Turn the Techstream on.

(d) Enter following menus: Body Electrical / Combination Meter / Data List.

(e) Read the Data List according to the display on the Techstream.

Body Electrical > Combination Meter > Data List

Tester Display	Measurement Item	Range	Normal Condition	Diagnostic Note
Fuel Input	Fuel input	Min.: 0 L, Max.: 127.5 L	Fuel receiver gauge indicates F: 64.8 L Fuel receiver gauge indicates 3/4: 54.0 L Fuel receiver gauge indicates 1/2: 36.0 L Fuel receiver gauge indicates 1/4: 18.0 L Fuel receiver gauge indicates E: 7.2 L	Unit: Liter

Body Electrical > Combination Meter > Data List

Tester Display
Fuel Input

Result	Proceed to
Fuel level data displayed on the Techstream is almost the same as the fuel receiver gauge indication.	A
Fuel level data displayed on the Techstream differs from the fuel receiver gauge indication.	B

A

REPLACE COMBINATION METER ASSEMBLY

B

9.	CHECK HARNESS AND CONNECTOR (COMBINATION METER ASSEMBLY - FUEL SUCTION TUBE WITH PUMP AND GAUGE ASSEMBLY)

(a) Disconnect the J10 combination meter assembly connector.

(b) Disconnect the S10 fuel suction tube with pump and gauge assembly connector.

(c) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection	Condition	Specified Condition
J10-27 (FR) - S10-2 (S)	Always	Below 1 Ω
J10-28 (FE) - S10-3 (FE)	Always	Below 1 Ω
J10-18 (FV) - S10-1 (FV)	Always	Below 1 Ω
J10-27 (FR) or S10-2 (S) - Body ground	Always	10 kΩ or higher
J10-28 (FE) or S10-3 (FE) - Body ground	Always	10 kΩ or higher
J10-18 (FV) or S10-1 (FV) - Body ground	Always	10 kΩ or higher

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

10.	INSPECT FUEL SENDER GAUGE ASSEMBLY

(a) Remove the fuel sender gauge assembly.

Click here

(b) Inspect the fuel sender gauge assembly.

Click here

OK:

Fuel sender gauge assembly is normal.

NG

REPLACE FUEL SENDER GAUGE ASSEMBLY

OK

11.	INSPECT FUEL SUCTION TUBE WITH PUMP AND GAUGE ASSEMBLY

(a) Measure the resistance according to the value(s) in the table below. Standard Resistance: Tester Connection Condition Specified Condition A-2 - B-1 Always Below 1 Ω A-1 - B-3 Always Below 1 Ω A-3 - B-2 Always Below 1 Ω A-1 - A-2 or B-2 - B-3 Always 10 kΩ or higher A-2 - A-3 or B-1 - B-2 Always 10 kΩ or higher A-1 - A-3 or B-1 - B-3 Always 10 kΩ or higher

*a Component without harness connected (Fuel Suction Tube with Pump and Gauge Assembly)

OK

REPLACE COMBINATION METER ASSEMBLY

NG

REPLACE FUEL SUCTION TUBE WITH PUMP AND GAUGE ASSEMBLY

12.	CONFIRM MODEL

(a) Choose the model to be inspected.

Result	Proceed to
for Optitron Meter Type	A
for TFT Meter Type	B

B

GO TO STEP 14

A

13.	PERFORM ACTIVE TEST USING TECHSTREAM (FUEL METER OPERATION)

(a) Connect the Techstream to the DLC3.

(b) Turn the engine switch on (IG).

(c) Turn the Techstream on.

(d) Enter following menus: Body Electrical / Combination Meter / Active Test.

(e) Perform the Active Test according to the display on the Techstream.

Body Electrical > Combination Meter > Active Test

Tester Display	Measurement Item	Control Range	Diagnostic Note
Fuel Meter Operation	Fuel receiver gauge	OFF, Sender E, Empty, Warning, 1/4, 1/2, 3/4, Full, Sender F	-

Body Electrical > Combination Meter > Active Test

Tester Display
Fuel Meter Operation

OK:

Fuel receiver gauge indication is normal.

NG

REPLACE COMBINATION METER ASSEMBLY

OK

14.	CHECK FOR DTC

(a) Check if SFI system DTCs are output.

Click here

Powertrain > Engine > Trouble Codes

Result	Proceed to
SFI system DTCs are not output.	A
SFI system DTCs are output.	B

B

GO TO SFI SYSTEM

A

15.	CHECK FOR DTC

(a) Check if vehicle stability control system DTCs are output.

Click here

Chassis > Brake/EPB > Trouble Codes

Result	Proceed to
Vehicle stability control system DTCs are not output.	A
Vehicle stability control system DTCs are output.	B

B

GO TO VEHICLE STABILITY CONTROL SYSTEM

A

16.	CHECK FOR DTC

(a) Check if meter / gauge system DTCs are output.

Click here

Body Electrical > Combination Meter > Trouble Codes

Result	Proceed to
DTC B1500 is not output.	A
DTC B1500 is output.	B

B

GO TO DTC B1500

A

17.	INSPECT FUEL RECEIVER GAUGE

(a) Disconnect the cable from the negative (-) battery terminal to reset the fuel receiver gauge.

HINT:

Check that the engine switch is turned off before disconnecting the cable from the negative (-) battery terminal.

(b) Connect the cable to the negative (-) battery terminal and turn the engine switch on (IG).

(c) Check if the fuel receiver gauge reading corresponds with the amount of fuel remaining in the fuel tank assembly.

Result	Proceed to
Fuel receiver gauge reading corresponds with the amount of fuel remaining in the fuel tank assembly.	A
Fuel receiver gauge reading does not correspond with the amount of fuel remaining in the fuel tank assembly.	B

A

END

B

GO TO STEP 8

18.	CHECK FOR DTC

(a) Check if SFI system DTCs are output.

Click here

Powertrain > Engine > Trouble Codes

Result	Proceed to
SFI system DTCs are not output.	A
SFI system DTCs are output.	B

B

GO TO SFI SYSTEM

A

19.	CHECK FOR DTC

(a) Check if vehicle stability control system DTCs are output.

Click here

Chassis > Brake/EPB > Trouble Codes

Result	Proceed to
Vehicle stability control system DTCs are not output.	A
Vehicle stability control system DTCs are output.	B

B

GO TO VEHICLE STABILITY CONTROL SYSTEM

A

20.	INSPECT FUEL TANK ASSEMBLY

HINT:

Inspect the fuel tank assembly for deformation, foreign matter or an improperly installed fuel receiver gauge, as this may be the cause of the fuel receiver gauge malfunction.

(a) Visually check the fuel tank assembly for any abnormalities.

(b) Check if there is an excessive amount of foreign matter in the fuel tank assembly.

(c) Check the installation condition of the fuel tank assembly and fuel sender gauge assembly.

Result	Proceed to
Normal	A
Appearance of the fuel tank assembly is abnormal.	B
There is an excessive amount of foreign matter in the fuel tank assembly.	C
The fuel tank assembly or fuel sender gauge assembly is not installed correctly.	D

A

REPLACE COMBINATION METER ASSEMBLY

B

REPLACE FUEL TANK ASSEMBLY

C

CLEAN INSIDE OF FUEL TANK ASSEMBLY

D

INSTALL FUEL TANK ASSEMBLY OR FUEL SENDER GAUGE ASSEMBLY CORRECTLY