Q: My 2005 infiniti qx56 is not starting. It is as if the fuel pump switch was triggered. it acts as if is going to turn on but does

Typically if the security system is preventing the vehicle from starting, the security light may be flashing. You vehicle’s keys are equipped with a transponder in each key. This is a computer chip that changes codes every time the vehicle is started. The ignition/security system reads the transponder codes when you turn the ignition on. If all is functioning properly, the security system will recognize the key and allow the vehicle to start. If it does not recognize the key, the security system may not allow the fuel pump, ignition, or both, to power up. Try to start the vehicle with another key if you have one. If it starts, then the first key is faulty and has to be replaced. If you do not have another key, you may be able to take the key to your local Infiniti dealership for them to check it. If the key is good, then the fault is elsewhere. Other components or sensors can be the cause. The crankshaft sensor for example. The engine control unit relies on the crankshaft position sensor to relay information as to the position of each cylinder. This is in order to control spark and fuel injector firing times. When cranking the engine, the engine control unit looks for the crankshaft sensor signal. If it does not get those signals, the fuel pump, ignition system, or both may also not power up. If the key is not the issue, have a certified technician look into the no start condition in order to find and correct the issue.