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.
Taillight Relay Circuit
Backprobe for voltage between door lock ECU harness connector terminal No. 4 and ground. When LOCK button on transmitter is pressed, voltage should pulse once. When UNLOCK button on transmitter is pressed, voltage should pulse twice. If voltage is not as specified, replace door lock ECU. If voltage is as specified, repair taillight circuit between door lock ECU and taillight relay.
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
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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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