the12volt.com spacer
the12volt.com spacer
the12volt.com spacer
the12volt.com spacer
icon

12v to battery or not, remote start


Post ReplyPost New Topic
< Prev Topic Next Topic >
dave151 
Member - Posts: 8
Member spacespace
Joined: October 24, 2004
Posted: December 11, 2007 at 3:49 PM / IP Logged  

Hey all,

This weekend i'm going to install a R/S (autostart 1755) and bypass (idatalink) in my 07 Ford Sporttrac.  I've been searching around regarding the 12V constant feed.  Some say I should run from the Bat and others say it's fine.  The 12V constant in the ignition harness is only 15amp.  I've been flipping through my Ford DVD and the blower motor and starter are both run off relays which means i'm really only powering relays with my remote starter.  I'm going to use the -12v output for the parking lights to keep the current down too.  I should be fine to wire the 2 12v bat leads and bypass to the ignition harness right?  I intend on replacing the 30 amp fuses with 15's too since that's what i'd be limited to.  I also don't like the thought of trying to run more current through factory wires that are only designed for 15amp anyway.

I'm just trying to provide a solid explanation since some of them are confusing to say the least.

chriswallace187 
Gold - Posts: 1,661
Gold spacespace
Joined: March 11, 2002
Location: Pennsylvania, United States
Posted: December 11, 2007 at 4:26 PM / IP Logged  
Provided that the only things drawing current are the control modules and the ignition harness, it shouldn't be a problem. Current draw on a remote start and bypass, just the brains, is under 5 amps. As long as you're only using the low current (-) outputs all is golden.
Any 12v + lead that will drive a component directly(e.g. lights, doorlock actuators I would run to the battery, or to the usual source for that component. I've done a couple '04-up F150s and used a relay at the parking light switch since the ignition is only a 20A feed.
C Renner's Auto Electronix
My service is cheap, quick, and good - pick any two
dave151 
Member - Posts: 8
Member spacespace
Joined: October 24, 2004
Posted: December 11, 2007 at 5:05 PM / IP Logged  
I'm still on the fence.  I may run positive parking lights because I have autolamps and if the switch is left in auto the lights won't work with the neg trigger.  It may be easier to tie everything to a 30 amp 10 gauge wire from the bat anyhow. 
howie ll 
Pot Metal - Posts: 16,466
Pot Metal spacespace
Joined: January 09, 2007
Location: United Kingdom
Posted: December 12, 2007 at 3:42 AM / IP Logged  
If you run from the battery AND fuse at the battery end you are playing safe electronically but you loose out security wise. Is there no heavy duty supply such as the fusebox that you could tap into inside the vehicle?
dave151 
Member - Posts: 8
Member spacespace
Joined: October 24, 2004
Posted: December 12, 2007 at 10:06 AM / IP Logged  
Why would I loose out security wise?  The hood is opened from inside the car.
KPierson 
Platinum - Posts: 3,526
Platinum spaceThis member consistently provides reliable informationspace
Joined: April 14, 2005
Location: Ohio, United States
Posted: December 12, 2007 at 10:29 AM / IP Logged  

I've never bought in to the 'lose security' arguement.  If a thief pops your hood and does not find an alarm power wire they can still cut the main power wire to the battery, rendering the system useless regardless of how it is connected.  They would then have time, with the alarm dead, to disable the alarm before reconnecting the battery.  No offense Howie, but most installers that are against wiring to the battery are actually against the extra work involved.

If your 12vdc power wire is only fused at 15A then there really isn't a point to dropping the fuses down from 30 to 15.  Those fuses are to protect the wiring, which is capable of carrying 30A per wire.  If you drop them down to two seperate 15A fuses that is still 30A of capacity because the fuses are in parallel.  So, you won't limit the current of the remote start to the factory 15A fuse.  It won't hurt anything to drop them down, but it won't help you the way that you think it will. 

The one thing to keep in mind when using the main battery wire under the dash is that if anything goes wrong with the remote start it is possible that it will blow the main factory fuses.  On my G35 the factory fuse is NOT an auto parts store fuse, it is a dealer order fuse that costs $15 and takes two days to get.  You do NOT want to blow these fuses, especially on a customers car in the bay.  In cases like that you are better off going directly to the battery and fuseing everything with your own fuses.  That way, if a fuse blows you will have the ability to replace it easily, and it won't prevent anything else from working.

Kevin Pierson
Chris Luongo 
Platinum - Posts: 3,746
Platinum spaceThis member consistently provides reliable informationspace
Joined: May 21, 2002
Location: Massachusetts, United States
Posted: December 12, 2007 at 11:26 AM / IP Logged  
You're fine with the constant-power feed at the ignition switch, provided you don't also add a bunch of high-current accessories.
For example, if you installed multiple sirens, window rollup modules, an air horn triggered by the alarm, then you'd want to get your constant power somewhere else.
Is the 07 Sport Trac still based on the Ranger? I can say that I've used positive parking lights in '07 Escapes with no troubles.
Be sure to fuse your remote starter with a fuse that's SMALLER than the factory one. You said the factory wire is fused at 10 amps, right?
In that case, power your whole setup through one 7.5 amp fuse. That way, if your install shorts out to ground, you only blow the fuse for the remote starter, but the car still runs and drives.
If you were to just leave the 30-amp fuse(s) in place, it would be the same as not using any fuses at all.
I used to work for a retailer that was obsessed with selling high-markup accessories, and made a regular practice of selling customers amplifier wiring kits along with remote starters.
dave151 
Member - Posts: 8
Member spacespace
Joined: October 24, 2004
Posted: December 12, 2007 at 12:43 PM / IP Logged  

I just like the idea of running a seperate line from the box under the hood.  I was going to tap in to the stud before where the main fuse is.  I have to go through the firewall with 2 wires whats one more in the grand scheme of things.  The factory wiring is 15 amp so I figured i'll leave each R/S line the ability to use the factory amperage.  I plan on using the neg triggers whenever possible anyhow.

howie ll 
Pot Metal - Posts: 16,466
Pot Metal spacespace
Joined: January 09, 2007
Location: United Kingdom
Posted: December 12, 2007 at 12:46 PM / IP Logged  
Kevin, going to battery or not is like arguing about IDC connectors, solder or crimp etc we will never resolve this. All I  can point out is that up to G4, ALL Cliffords hated NOT going to the battery so that was the correct procedure for power and ground. The early prox sensors went crazy if you used a local power supply that delivered less than 12.3 volts. Remember in the UK most  alarms are Cat I with battery back-up sirens and mandatory hood switches. Note in my own car I went to the battery, because the ignition supply looked too thin. Going to the ign switch never seems to fail on Toyotas and BMW's with 2 permanent ignition leads, also fusebox permanent is often unfused at battery and thick enough for about 80 amps. Having said that I would double check the voltage at my live and ground points and want to see at least 12.5volts. Regards Howard.
KPierson 
Platinum - Posts: 3,526
Platinum spaceThis member consistently provides reliable informationspace
Joined: April 14, 2005
Location: Ohio, United States
Posted: December 12, 2007 at 3:07 PM / IP Logged  

I totally agree with you Howie.

I've got my power from the igntion wiring in certain cases, but I always prefer going to the battery to achieve isolation from factory fuses, and to provide the customer a quick and easy way to shut off the alarm system in case something has failed.  I just hate the excuse that you are making the alarm less secure by going to the battery because you are not in any way doing so.  If a thief has access to the battery it doesn't matter where your alarm is connected, it can be disabled. 

Kevin Pierson
Page of 2

  Printable version Printable version Post ReplyPost New Topic
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot delete your posts in this forum
You cannot edit your posts in this forum
You cannot create polls in this forum
You cannot vote in polls in this forum

  •  
Search the12volt.com
Follow the12volt.com Follow the12volt.com on Facebook
Tuesday, April 20, 2021 • Copyright © 1999-2021 the12volt.com, All Rights Reserved Privacy Policy & Use of Cookies
Disclaimer: *All information on this site ( the12volt.com ) is provided "as is" without any warranty of any kind, either expressed or implied, including but not limited to fitness for a particular use. Any user assumes the entire risk as to the accuracy and use of this information. Please verify all wire colors and diagrams before applying any information.

Secured by Sectigo
the12volt.com spacer
the12volt.com spacer
the12volt.com spacer
Support the12volt.com
Top
the12volt.com spacer
the12volt.com spacer