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
2010 Scion tC L4-2.4L (2AZ-FE)SECTION Testing and Inspection
2AZ-FE ENGINE CONTROL SYSTEM: 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. INSPECT CIRCUIT OPENING RELAY
(a) Measure the resistance between the terminals.
Standard resistance:
(b) If the result is not as specified, replace the instrument panel junction block.
3. CONNECT CABLE TO NEGATIVE BATTERY TERMINAL
4. PERFORM INITIALIZATION
(a) Perform initialization Testing and Inspection.
NOTICE:
Certain systems need to be initialized after disconnecting and reconnecting the cable from the negative (-) battery
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.