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Q: Wire

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Need to find the color wire that starts the whole car connected to the ignition

My car has 21241 miles.
My car has an automatic transmission.

Your vehicle does not rely on a single ignition wire at start up. When you turn the ignition key, many different circuits are actuated, even within just the ignition system (not to mention the fuel system), corresponding to different vehicle components such as the PCM, primary side of the ignition coil(s), cam and crankshaft sensors and on and on. Each wire is of a different color code and a different gauge (size) as well. If your vehicle is not starting and you think the no start condition might be related to a wiring fault, below is a procedure that you can follow.


Prior to performing diagnostics be sure that you have a fully charged battery that passes a load test. Then, confirm that the engine immobilizer system (security system) is not activated on your vehicle thus preventing the car from starting. If the immobilizer system is on, you may see a security warning light. To temporarily override the immobilizer system, see these instructions. With a fully charged battery and the immobilizer system off, if the starter motor does not operate at that point, either there is no power to the starter motor, hence the starter circuit would have to be diagnosed, or the starter itself is bad and it would be replaced. On the other hand, if you do have a fully charged battery that is powering a starter motor that is turning the engine over rapidly, at sufficient RPM, but the engine does not catch and run, that means that there is an ignition, fuel, air induction, or mechanical fault in the engine that will have to be repaired. Be sure there is adequate fuel in the fuel tank and that the fuel is not old. Check for adequate fuel pressure (does the in-tank fuel pump whirr momentarily at the instant you turn the key to the "on" position?; if not, you have a dead fuel pump), injector operation, and a spark at the spark plugs. If the simple checks I have outlined above do not result in the car starting the recommended service to request is a no start diagnostic during which the responding certified mechanic will get this resolved for you. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

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