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.
Automatic Shutdown (ASD) Relay Input Signal
A 12-volt signal to PCM indicates that ASD has been activated. ASD relay is located in Power Distribution Center (PDC). ASD relay is battery voltage source for HO2S heating element, ignition coil, generator field winding and fuel injectors. If PCM does not see a 12-volt signal when ASD relay should be activated, a Diagnostic Trouble Code (DTC) No. 42 AUTO SHUTDOWN RELAY CONTROL CIRCUIT will be set.
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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.