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.
Main Relay (Computer/Fuel System): Testing and Inspection
2006 Scion xB L4-1.5L (1NZ-FE)SECTION Testing and Inspection
CIRCUIT OPENING RELAY
ON-VEHICLE INSPECTION
1. DISCONNECT CABLE FROM NEGATIVE BATTERY TERMINAL
CAUTION: Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to prevent airbag and seat belt pretensioner activation.
2. REMOVE CIRCUIT OPENING RELAY (Marking: C/ OPN)
a. Remove the circuit opening relay from the instrument panel junction block.
3. INSPECT CIRCUIT OPENING RELAY
a. Measure the resistance of the circuit opening relay.
If the result is not as specified, replace the circuit opening relay.
4. INSTALL CIRCUIT OPENING RELAY
5. CONNECT CABLE TO NEGATIVE BATTERY TERMINAL
ON-VEHICLE INSPECTION
1. DISCONNECT CABLE FROM NEGATIVE BATTERY TERMINAL
CAUTION: Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to prevent airbag and seat belt pretensioner activation.
2. REMOVE CIRCUIT OPENING RELAY (Marking: C/ OPN)
a. Remove the circuit opening relay from the instrument panel junction block.
3. INSPECT CIRCUIT OPENING RELAY
a. Measure the resistance of the circuit opening relay.
If the result is not as specified, replace the circuit opening relay.
4. INSTALL CIRCUIT OPENING RELAY
5. CONNECT CABLE TO NEGATIVE BATTERY TERMINAL
RENDER: 1.0x
NO RELATED
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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.