Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Inspection Procedure
When using intelligent tester:
- PERFORM ACTIVE TEST BY INTELLIGENT TESTER (OPERATION OF CIRCUIT OPENING RELAY)
- Connect an intelligent tester to the DLC3.
- Turn the ignition switch to ON and turn the tester ON.
- Select the following menu items: DIAGNOSIS / ENHANCED OBD II / ACTIVE TEST / FUEL PUMP/ SPD.
- Check whether operating sounds can be heard while operating the relay using the tester.
OK:
Operating sounds can be heard from relay.
OK : Go to step 7
NG: Go to Next Step
- INSPECT ECM POWER SOURCE CIRCUIT
- Inspect the ECM power source circuit (See ECM POWER SOURCE CIRCUIT ).
NG: REPAIR OR REPLACE ECM POWER SOURCE CIRCUIT
OK : Go to Next Step
- INSPECT CIRCUIT OPENING RELAY
- Remove the circuit opening relay from the instrument panel J/B.
- Check the circuit opening relay resistance.
Standard resistance
RESISTANCE SPECIFICATIONSTester Connections Specified Conditions 3-5 10 kΩ or higher 3-5 Below 1 Ω (when battery voltage applied to terminals 1 and 2) - Reinstall the circuit opening relay.
NG: REPLACE CIRCUIT OPENING RELAY
OK : Go to Next Step
- INSPECT ECM (FC VOLTAGE)
- Turn the ignition switch to ON.
- Measure the voltage between the terminals of the E3 and E6 ECM connectors.
Standard voltage
STANDARD VOLTAGE SPECIFICATIONSTester Connections Specified Conditions FC (E6-10) - E1 (E3-5) Between 9 V and 14 V
OK : REPLACE ECM
NG: Go to Next Step
- CHECK HARNESS AND CONNECTOR (IGNITION SWITCH - CIRCUIT OPENING RELAY)
- Disconnect the I11 ignition switch connector.
- Remove the circuit opening relay from the instrument panel J/B.
- Check the resistance.
Standard resistance (Check for open)
STANDARD RESISTANCE SPECIFICATIONS FOR OPENTester Connections Specified Conditions IG2 (I11-6) - Instrument panel J/B (Circuit opening relay terminal 1) Below 1 Ω Standard resistance (Check for short)
STANDARD RESISTANCE SPECIFICATIONS (FOR SHORT)Tester Connections Specified Conditions IG2 (I11-6) or Instrument panel J/B (Circuit opening relay terminal 1) - Body ground 10 kΩ or higher - Reinstall the circuit opening relay.
- Reconnect the ignition switch connector.
NG: REPAIR OR REPLACE HARNESS OR CONNECTOR
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
OK : Go to Next Step
- CHECK HARNESS AND CONNECTOR (ECM - CIRCUIT OPENING RELAY)
- Disconnect the E6 ECM connector.
- Remove the circuit opening relay from the instrument panel J/B.
- Check the resistance.
Standard resistance (Check for open)
STANDARD RESISTANCE SPECIFICATIONS FOR OPENTester Connections Specified Conditions FC (E6-10) - Instrument panel J/B (Circuit opening relay terminal 2) Below 1 Ω Standard resistance (Check for short)
STANDARD RESISTANCE SPECIFICATIONS (FOR SHORT)Tester Connections Specified Conditions FC (E6-10) or Instrument panel J/B (Circuit opening relay terminal 2) - Body ground 10 kΩ or higher - Reinstall the circuit opening relay.
- Reconnect the ECM connector.
NG: REPAIR OR REPLACE HARNESS OR CONNECTOR
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
OK : REPLACE ECM
- INSPECT FUEL PUMP
- Inspect the fuel pump (See INSPECTION ).
NG: REPLACE FUEL PUMP
OK : Go to Next Step
- CHECK HARNESS AND CONNECTOR (CIRCUIT OPENING RELAY - FUEL PUMP, FUEL PUMP - BODY GROUND)
- Remove the circuit opening relay from the instrument panel J/B.
- Disconnect the F10 fuel pump connector.
- Check the resistance.
Standard resistance (Check for open)
STANDARD RESISTANCE SPECIFICATIONS FOR OPENTester Connections Specified Conditions Instrument panel J/B (Circuit opening relay terminal 3) - Fuel pump (F10-4) Below 1 Ω Fuel pump (F10-5) - Body ground Below 1 Ω Standard resistance (Check for short)
STANDARD RESISTANCE SPECIFICATIONS (FOR SHORT)Tester Connections Specified Conditions Instrument panel J/B (Circuit opening relay terminal 3) or Fuel pump (F10-4) - Body ground 10 kΩ or higher - Reconnect the fuel pump connector.
- Reinstall the circuit opening relay.
NG: REPAIR OR REPLACE HARNESS OR CONNECTOR
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
OK : CHECK AND REPAIR HARNESS AND CONNECTOR (EFI RELAY - CIRCUIT OPENING RELAY)
When Using OBD II Scan Tool:
- CHECK FUEL PUMP (OPERATION)
- Turn the ignition switch to ON.
- Connect terminals FC and E1 of the ECM connector.
- Check for fuel pressure in the fuel inlet hose when it is pinched off.
OK:
There is pressure in fuel inlet hose.
HINT:
At this time, operating sounds can be heard from the fuel pump.
OK : PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE
NG: Go to Next Step
- INSPECT ECM POWER SOURCE CIRCUIT
- Inspect the ECM power source circuit (See ECM POWER SOURCE CIRCUIT ).
NG: REPAIR OR REPLACE ECM POWER SOURCE CIRCUIT
OK : Go to Next Step
- INSPECT CIRCUIT OPENING RELAY
- Remove the circuit opening relay from the instrument panel J/B.
- Check the circuit opening relay resistance.
Standard resistance
RESISTANCE SPECIFICATIONSTester Connections Specified Conditions 3-5 10 kΩ or higher 3-5 Below 1 Ω (when battery voltage Is applied to terminals 1 and 2) - Reinstall the circuit opening relay.
NG: REPLACE CIRCUIT OPENING RELAY
OK : Go to Next Step
- INSPECT ECM (FC VOLTAGE)
- Turn the ignition switch to ON.
- Measure the voltage between the terminals of the E3 and E6 ECM connectors.
Standard voltage
STANDARD VOLTAGE SPECIFICATIONSTester Connections Specified Conditions FC (E6-10) - E1 (E3-5) Between 9 V and 14 V
OK : REPLACE ECM
NG: Go to Next Step
- CHECK HARNESS AND CONNECTOR (IGNITION SWITCH - CIRCUIT OPENING RELAY)
- Disconnect the I11 ignition switch connector.
- Remove the circuit opening relay from the instrument panel J/B.
- Check the resistance.
Standard resistance (Check for open)
STANDARD RESISTANCE SPECIFICATIONS FOR OPENTester Connections Specified Conditions IG2 (I11-6) - Instrument panel J/B (Circuit opening relay terminal 1) Below 1 Ω Standard resistance (Check for short)
STANDARD RESISTANCE SPECIFICATIONS (FOR SHORT)Tester Connections Specified Conditions IG2 (I11-6) or Instrument panel J/B (Circuit opening relay terminal 1) - Body ground 10 kΩ or higher - Reinstall the circuit opening relay.
- Reconnect the ignition switch connector.
NG: REPAIR OR REPLACE HARNESS OR CONNECTOR
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
OK : Go to Next Step
- CHECK HARNESS AND CONNECTOR (ECM - CIRCUIT OPENING RELAY)
- Disconnect the E6 ECM connector.
- Remove the circuit opening relay from the instrument panel J/B.
- Check the resistance.
Standard resistance (Check for open)
STANDARD RESISTANCE SPECIFICATIONS FOR OPENTester Connections Specified Conditions FC (E6-10) - Instrument panel J/B (Circuit opening relay terminal 2) Below 1 Ω Standard resistance (Check for short)
STANDARD RESISTANCE SPECIFICATIONS (FOR SHORT)Tester Connections Specified Conditions FC (E6-10) or Instrument panel J/B (Circuit opening relay terminal 2) - Body ground 10 kΩ or higher - Reinstall the circuit opening relay.
- Reconnect the ECM connector.
NG: REPAIR OR REPLACE HARNESS OR CONNECTOR
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
OK : Go to Next Step
- INSPECT FUEL PUMP
- Inspect the fuel pump (See INSPECTION ).
NG: REPLACE FUEL PUMP
OK : Go to Next Step
- CHECK HARNESS AND CONNECTOR (CIRCUIT OPENING RELAY - FUEL PUMP, FUEL PUMP - BODY GROUND)
- Remove the circuit opening relay from the instrument panel J/B.
- Disconnect the F10 fuel pump connector.
- Check the resistance.
Standard resistance (Check for open)
STANDARD RESISTANCE SPECIFICATIONS FOR OPENTester Connections Specified Conditions Instrument panel J/B (Circuit opening relay terminal 3)-Fuel pump (F10-4) Below 1 Ω Fuel pump (F10-5) - Body ground Below 1 Ω Standard resistance (Check for short)
STANDARD RESISTANCE SPECIFICATIONS (FOR SHORT)Tester Connections Specified Conditions Instrument panel J/B (Circuit opening relay terminal 3) or Fuel pump (F10-4) - Body ground 10 kΩ or higher - Reconnect the fuel pump connector.
- Reinstall the circuit opening relay.
NG: REPAIR OR REPLACE HARNESS OR CONNECTOR
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
OK : CHECK AND REPAIR HARNESS AND CONNECTOR (EFI RELAY - CIRCUIT OPENING RELAY)
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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