Q: Interior lights work but car won't start and power locks won't work 97 Honda passport

You possibly have a dead battery. Batteries that are "partly" dead can often still run lights, dash lights and so forth but will not have enough power to run the starter motor and start the car. The very first thing to do is be sure you have a fully, 100% charged battery that passes a load test. If the battery passes a load test be sure it is NOT a marginal pass in which case you should simply install a new battery to reduce diagnostic headaches. Batteries are a VERY important component in a car’s electrical system. Once you have a fully functioning, preferably new battery (fully charged before you leave the store), if the starting system still does not function, there are only a relatively limited number of causes. Broadly, either the starter motor/solenoid assembly is faulty or the electrical circuit supplying the motor has a fault. That circuit begins at the battery and includes grounds, wiring (some of which is very heavy cabling), fuses, relays, the ignition switch and terminations. Basically, the starter is either getting power or it isn’t. If the starter motor is getting power but it doesn’t work, the starter is condemned and replaced. Alternatively, if there is no power to the starter, then the starter circuit is traced until the fault in the circuit is found. Notably, faults can include high resistances, due to corrosion, wire strand breaks, or loose terminals, which can only be diagnosed using a voltage drop test. If you desire that a certified mechanic resolve this promptly, please simply request a no start diagnostic and the responding mechanic will get it diagnosed and repaired for you, including installing a new battery if required. Please let us know if you have further concerns or questions as we are always here to help you.