Radio install Question..
Thread Starter
|
Logistics Pro
Joined: Mar 2001
Posts: 4,157
Likes: 3
Radio install Question..
My brother who had my truck installed the current radio with just the positive and negative wires connected and I have to turn the radio off every time I get out. Where do I connect the yellow accessory wire? Does it matter? Thanks.
More Turbo
Joined: Feb 2008
Posts: 641
Likes: 25
From: Port Charlotte, Florida
The yellow wire needs to be a constant 12v source so the clock and presets stay set. The red wire needs to be on a 12v source thats only hot with the key in the on and accessary position.
Thread Starter
|
Logistics Pro
Joined: Mar 2001
Posts: 4,157
Likes: 3
Ah, I had it backwards. Thanks. Where is the best place to connect the red wire?
MSEE
Joined: Apr 2004
Posts: 10,386
Likes: 35
From: Austin, TX
If your original harness hasn't been hacked, you should have a green 2-connector pigtail behind the dash that served as the original radio power connector. One wire is blue with a red stripe, this is your dash illumination. The other is yellow. I'm not sure of the stripe color; I think it's red (could be wrong). That wire is hot-in-accessory which is what you want to use.
I know this sounds backwards - yellow wire of the aftermarket radio to constant power, then red wire of the aftermarket radio to the yellow wire of the truck, but it's just how the convention came out.
I know this sounds backwards - yellow wire of the aftermarket radio to constant power, then red wire of the aftermarket radio to the yellow wire of the truck, but it's just how the convention came out.
Thread Starter
|
Logistics Pro
Joined: Mar 2001
Posts: 4,157
Likes: 3
If your original harness hasn't been hacked, you should have a green 2-connector pigtail behind the dash that served as the original radio power connector. One wire is blue with a red stripe, this is your dash illumination. The other is yellow. I'm not sure of the stripe color; I think it's red (could be wrong). That wire is hot-in-accessory which is what you want to use.
I know this sounds backwards - yellow wire of the aftermarket radio to constant power, then red wire of the aftermarket radio to the yellow wire of the truck, but it's just how the convention came out.
I know this sounds backwards - yellow wire of the aftermarket radio to constant power, then red wire of the aftermarket radio to the yellow wire of the truck, but it's just how the convention came out.
Thread Starter
|
Logistics Pro
Joined: Mar 2001
Posts: 4,157
Likes: 3
Ok, put in the newer radio last night. Got it so it turns off with the truck going off. fmc400, thanks, I tapped into the OEM pigtail for the accessory power. My question is my bro pulled the constant power from the back of the cigarette lighter. Is this a problem on for my radio? Should I wire the hot directly to the battery? Thanks.
Trending Topics
Senior User
Joined: Aug 2007
Posts: 160
Likes: 0
others might have a different opinion, but i think you should be ok with it being ran through there.
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
Top 6 Best Deals Available on New Fords & Lincolns Right Now
Brett Foote
This Hennessey Takes the Expedition Tremor's Off-Roading Capability to the Next Level
Verdad Gallardo
Top 10 Fords at 2026 Carlisle Ford Nationals
Joe Kucinski
3 Best / 3 Worst Parts of Modern Ford Ownership
Brett Foote
10 Amazing Upgrades That Solve Common Ford Truck Owner Headaches
Pouria Savadkouei
Every 2026 Ford Engine Explained
Brett Foote
10 Ugly Ford Trucks That We Still Kinda Love
Joe Kucinski
10 Things Every Truck Owner NEEDS (2026 Edition)
Michael S. Palmer
Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath
Verdad Gallardo
MSEE
Joined: Apr 2004
Posts: 10,386
Likes: 35
From: Austin, TX
If you never use the actual heating element part of the cigarette lighter, then it's definitely not a problem. That's how I've wired mine. I just use the lighter plug for plugging in a cell phone charger, GPS, etc. Those things don't draw much current.
If you do use the actual heating element to light cigarettes, then it's possible that if you have it heating up at the same time the radio is very loud, the fuse could blow. Or, the voltage seen at the radio power terminal could drop and the radio might shut off. Both of these scenarios are due to the fact that the heating element in the cigarette lighter draws a ridiculous amount of current. Some of the universal ones draw so much that they'll pop the factory rated fuse.
If you do use the actual heating element to light cigarettes, then it's possible that if you have it heating up at the same time the radio is very loud, the fuse could blow. Or, the voltage seen at the radio power terminal could drop and the radio might shut off. Both of these scenarios are due to the fact that the heating element in the cigarette lighter draws a ridiculous amount of current. Some of the universal ones draw so much that they'll pop the factory rated fuse.
Post Fiend
Joined: Jul 2004
Posts: 8,786
Likes: 28
From: Northern California
He shouldn't have a problem. As the Cigar lighter is plugged into the courtesy lamp circut on these old trucks, and so was the AM Digital display radio memory. Glove box lamp, vanity mirror lamps, etc...
Lt. Green/Yellow stripe wire. What that pigtail was for behind the dash, that you mentioned, BTW.
The constant power for the radio should only be used when the radio is off, anyway. For keep alive memory.
The Power for the amps should come from the switched source.
Lt. Green/Yellow stripe wire. What that pigtail was for behind the dash, that you mentioned, BTW.
The constant power for the radio should only be used when the radio is off, anyway. For keep alive memory.
The Power for the amps should come from the switched source.
Fleet Owner
Joined: Jan 2004
Posts: 26,007
Likes: 575
From: Brentwood,CA
No its the other way around. The constant hot is where the radio will draw its power from and let the microprocessor draw a few Mill Amps of power to keep the presets. The switched 12v simply turns the relay inside the radio to on. Notice how the constant hot wire is 14ga and the switched is 18ga wire on most aftermarket radios.
Thread Starter
|
Logistics Pro
Joined: Mar 2001
Posts: 4,157
Likes: 3
Thanks. I have installed aftermarket amps and head units years ago and I always pulled off the battery. Ran a heavy gauge wire from the bat to a distribution block, then to the amp and HU. This head unit I installed is an older shaft style cassette deck and only puts out 8wx2. I didn't know how many amps the head unit could draw.
Post Fiend
Joined: Jul 2004
Posts: 8,786
Likes: 28
From: Northern California
No its the other way around. The constant hot is where the radio will draw its power from and let the microprocessor draw a few Mill Amps of power to keep the presets. The switched 12v simply turns the relay inside the radio to on. Notice how the constant hot wire is 14ga and the switched is 18ga wire on most aftermarket radios.
Thread
Thread Starter
Forum
Replies
Last Post
denisontexas
1948 - 1956 F1, F100 & Larger F-Series Trucks
2
Jan 12, 2002 07:36 PM
