# Car won’t start after installing amp/sub? **URL:** \ **Category:** Maintenance/Repairs\ **Created:** [August 16, 2019, 1:44pm UTC](https://community.cartalk.com/t/car-won-t-start-after-installing-amp-sub/146827 "2019-08-16T13:44:26Z")\ **Posts on this page:** 10\ **Page:** 1
**Author:** ![Braydon\_Morgan](https://avatars.discourse-cdn.com/v4/letter/b/dfb087/32.png) [@Braydon\_Morgan](https://community.cartalk.com/u/Braydon_Morgan)\ **Post date:** [August 16, 2019, 1:44pm UTC](https://community.cartalk.com/t/car-won-t-start-after-installing-amp-sub/146827/1 "2019-08-16T13:44:27Z")
My buddy and I worked on installing an amp/ sub combo , ran the power wire to the Negative battery terminal. When we were finished, we tried starting the truck, nothing other than clicking, so I adjusted the battery terminals, and the truck started perfectly, but the amp wasn’t coming on (power light was not lit) so we said we would work on it tomorrow. My buddy woke up this morning and the truck wouldn’t start, we never disconnected the amp from the battery, so is it possible that even tho the amp wasn’t turning on, that it was still drawing power from the battery? EDIT: we installed the power wire to the positive battery terminal, NOT the negative. ---
**Author:** ![Mustangman](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/mustangman/32/44130_2.png) [@Mustangman](https://community.cartalk.com/u/Mustangman)\ **Post date:** [August 16, 2019, 2:04pm UTC](https://community.cartalk.com/t/car-won-t-start-after-installing-amp-sub/146827/2 "2019-08-16T14:04:16Z")
Yes, the amp could be drawing power while the car is off especially directly wired to the battery. There should be a trigger wire connected to the radio head unit to turn the amp on when the head unit turns on. It also sounds like your battery terminals are not tight and-or corroded as well. Check both. ---
**Author:** ![Braydon\_Morgan](https://avatars.discourse-cdn.com/v4/letter/b/dfb087/32.png) [@Braydon\_Morgan](https://community.cartalk.com/u/Braydon_Morgan)\ **Post date:** [August 16, 2019, 2:46pm UTC](https://community.cartalk.com/t/car-won-t-start-after-installing-amp-sub/146827/4 "2019-08-16T14:46:44Z")
It could be drawing power even tho the amp/sub isn’t powering on? ---
**Author:** ![texases](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/texases/32/862_2.png) [@texases](https://community.cartalk.com/u/texases)\ **Post date:** [August 16, 2019, 2:59pm UTC](https://community.cartalk.com/t/car-won-t-start-after-installing-amp-sub/146827/5 "2019-08-16T14:59:04Z")
> [@Braydon\_Morgan](#): > > ran the power wire to the Negative battery terminal. Why? The power wire should go to the positive terminal, but should be appropriately switched. Have you ever done this kind of work? ---
**Author:** ![Mustangman](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/mustangman/32/44130_2.png) [@Mustangman](https://community.cartalk.com/u/Mustangman)\ **Post date:** [August 16, 2019, 3:24pm UTC](https://community.cartalk.com/t/car-won-t-start-after-installing-amp-sub/146827/6 "2019-08-16T15:24:08Z")
Actually, yes. Many electronic components in cars do draw current, small amounts, when off. Aftermarket amps, subs and head units are notorious for high draws when off and internal failures that cause those draws to be much higher. So high that it drains the battery overnight. It is called parasitic drain and if your battery continues to go dead overnight, you need to do a parasitic draw test to determine the cause. Aftermarket devices radios, alarms, and remote starters are usual suspects. ---
**Author:** ![Braydon\_Morgan](https://avatars.discourse-cdn.com/v4/letter/b/dfb087/32.png) [@Braydon\_Morgan](https://community.cartalk.com/u/Braydon_Morgan)\ **Post date:** [August 16, 2019, 3:28pm UTC](https://community.cartalk.com/t/car-won-t-start-after-installing-amp-sub/146827/7 "2019-08-16T15:28:16Z")
I made an edit stating we ran it to the positive, made a typo ---
**Author:** ![Braydon\_Morgan](https://avatars.discourse-cdn.com/v4/letter/b/dfb087/32.png) [@Braydon\_Morgan](https://community.cartalk.com/u/Braydon_Morgan)\ **Post date:** [August 16, 2019, 3:30pm UTC](https://community.cartalk.com/t/car-won-t-start-after-installing-amp-sub/146827/8 "2019-08-16T15:30:02Z")
Okay, so just charge up the battery, and then wire up the turn on wire ? But why wouldn’t the sub be working if it’s drawing power? Erin remote wiring or a bad ground? ---
**Author:** ![Mustangman](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/mustangman/32/44130_2.png) [@Mustangman](https://community.cartalk.com/u/Mustangman)\ **Post date:** [August 16, 2019, 3:35pm UTC](https://community.cartalk.com/t/car-won-t-start-after-installing-amp-sub/146827/9 "2019-08-16T15:35:55Z")
There are any number of reasons the amp is not working. You need to work with the wiring diagram supplied with the amp AND a volt-ohm meter so you can check voltages and ground resistance. ---
**Author:** ![Braydon\_Morgan](https://avatars.discourse-cdn.com/v4/letter/b/dfb087/32.png) [@Braydon\_Morgan](https://community.cartalk.com/u/Braydon_Morgan)\ **Post date:** [August 16, 2019, 4:13pm UTC](https://community.cartalk.com/t/car-won-t-start-after-installing-amp-sub/146827/10 "2019-08-16T16:13:33Z")
I’m almost positive the remote turn on wire was installed incorrectly, could this play a role in the sub not powering and the battery draining? ---
**Author:** ![Mustangman](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/mustangman/32/44130_2.png) [@Mustangman](https://community.cartalk.com/u/Mustangman)\ **Post date:** [August 16, 2019, 4:24pm UTC](https://community.cartalk.com/t/car-won-t-start-after-installing-amp-sub/146827/11 "2019-08-16T16:24:35Z")
Yes it can