Check engine light bypass

185

01:54:37

This switch represents the check engine light. The power source would be the cars cdi signal to the light. The current source is the alternator. With a pnp transistor in line with the base connected  with the alternator and the collector and emitter bypassing the the original circuit path, rerouting the current to light when powered by the key "on". When turned to "start", the current triggers the transistor and stops the ability to send power to the light. This is to fool emission checks in states that require your check engine light to pass for smog examination.

published 8 years ago

rich11292000

8 years ago

Sounds expensive. You can just take the bulb out. Remove the fuse.

minihuey

8 years ago

Hahahah that comment above. Regardless. Good job for creating a circuit solution!

kfafnis

6 years ago

They'll hook up their scan tool and it will indicate the MIL is active, even though the light is off

rockwog

2 years ago

They don't hook a scan tool to do a smog test in CA. They put a probe in your exhaust and put your car on dyno rollers. They aren't checking your cars computer or map. they only check the emission output at different rpms at load via the dyno rollers. And the very first thing they do is turn the ignition to the 'on' position to see of the check engine light comes on. Then they start the engine and check to see the check engine light is on again. If it's off when the ignition is on or of it comes on when the vehicle is started, it's an automatic fail.

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