If your vehicle's engine misfires, hesitates, stalls, gets poor mileage, is hard to start or has failed an emissions test, it clearly needs something, though a tune-up in the traditional sense might not be the cure. If you tell a repair shop your vehicle needs a tune-up, the mechanic should ask what you feel the signs are that you need maintenance before recommending any service. Just like a doctor should ask what symptoms you're experiencing, a mechanic should seek to diagnose the problem. And just as a doctor may recommend some tests, a mechanic may do the same.
Fixing Wiring Problems: Find an electrical schematic of your vehicle. This can be found either from information in your owner's manual or on the Internet. Trace the wiring from the fuse panel to the switch. You should refer to your electrical schematic for help. You want to make sure that there are no breaks in the connection from the fuse box to the switch. If you did not find a schematic, it might be easier to trace the wiring from the switch back to the fuse box to look for any breaks in the connection.
If the car's dashboard battery light comes on, you might be able to make it home or to a service facility for a repair. The car will continue running as long as some juice is left in the battery, but if the charging system isn't working or you have a bad alternator, your car's engine will stop running once the battery is drained. If you turn off the engine, you won't be able to restart it if the battery doesn't have enough charge left to power the engine's starter motor.
These can often be difficult to bolts to remove. You may need to use a ratchet with a long extension to provide the necessary angle to access and turn the bolts. Pull the motor and harness out as one assembly. Once you have the assembly removed, you can separate the two pieces and replace the one that is malfunctioning. Re-install the motorregulator assembly. Once you have replaced the malfunctioning part, whether it was the motor or the regulator, it is time to slide the assembly back into the door's interior and bolt it back into it's original position.