Does the starter work when the ignition switch is turned to the ACC position?
3 Answers
When the ignition switch is turned to the ACC position, the starter does not work. Here is some relevant information about the ignition switch: 1. The function of the ignition switch is to act as a system switch, and it requires a key to operate. This main circuit can freely turn the ignition coil on or off and can also be used for other electrical circuits. 2. The meanings of the ignition switch positions are: LOCK - locks the steering wheel and cuts off the power; ACC - the accessory power is turned on; ON - all vehicle power except the starter is turned on; START - the starter power is turned on and the engine starts. (After releasing the key, it will automatically return to the ON position).
I remember when I drove my old car, turning the ignition key to the ACC position would power the radio and lights, but the starter wouldn't make a sound. The ACC position is specifically designed to power vehicle accessories, like charging a phone or running the AC blower, without starting the engine. To actually engage the starter, you need to turn the key to the START position—that's the final detent where battery current directly feeds the starter to crank the engine. If you hear the starter engaging while in ACC, there's definitely a problem—possibly a stuck ignition switch, wiring short, or relay failure. This kind of malfunction is quite dangerous as it could drain the battery or damage components, so if you notice anything unusual, shut off the engine immediately and inspect it. It's best to drive to a reputable repair shop and have them use a diagnostic tool to check for electrical issues.
In automotive design, the ACC position of the ignition switch is primarily for powering onboard electrical devices like the radio or cigarette lighter charger without engaging the starter motor. The starter requires a dedicated signal to activate, which is only sent when the key is turned to the START position to rotate the engine crankshaft. If the starter operates when turned to ACC, this clearly indicates a system malfunction—possibly due to stuck internal contacts in the switch or a short circuit to ground. This can cause excessive current flow, draining the battery and potentially leading to overheating, fire hazards, or starter damage. If encountered while driving, immediately stop the vehicle, avoid attempting to start it, and first check if the relevant fuse in the fuse box has blown. If unresolved, consult a professional technician. Safety comes first—neglecting this could lead to serious consequences.
