79 F-350 WIRING Problem
Thread Starter
|
New User
Joined: Jan 2004
Posts: 5
Likes: 0
From: Mid-Michigan
79 F-350 WIRING Problem
Pushed the horn bar, lost EVERYTHING. Can start by jumping solenoid, dies as soon as jump removed. ALL power distribution gone, lights, interior - EVERYTHING! Any ideas?
New User
Joined: Oct 2003
Posts: 23
Likes: 0
From: Massachusetts
Check fusable links near the the battery. Some models also have a fuse link on the firewall on the drivers side. If they are blown they will STRETCH when you pull on them. Your horn might be shorted which may have caused the fault. I would disconnect the horn and check its resistance before pressing the horn bar after the power is restored. There may be a horn relay as well that could have caused the problem.
Thread Starter
|
New User
Joined: Jan 2004
Posts: 5
Likes: 0
From: Mid-Michigan
YES! I do have cruise control, and was kinda wondering about that too. I just bought the truck recently. They guy rebuilt the motor (400) and said he had trouble with power, but we thought it to be remedied by a seperate start button. I drove it before I bought it, and then drove it home - almost (about 40 miles). No electrical problems at all 'til I hit the horn bar, and then POOF, lost everything, instantly. Headlights, tail, marker, etc etc all worked 'til that moment. What's weird is I can start the motor by jumping the solenoid (and yes I tried another solenoid - same problem).
It's a beautiful truck, and I WILL get it right, even if it means a few hundred bucks for new wiring.
Thanks for the tip, I'll get back to you throughout the week as I have time to fiddle with it.
OH, where's the horn relay?
Also, I ordered the manual on CD from this site. Supposed to be FORD's manual. Know anything about it?
It's a beautiful truck, and I WILL get it right, even if it means a few hundred bucks for new wiring.
Thanks for the tip, I'll get back to you throughout the week as I have time to fiddle with it.
OH, where's the horn relay?
Also, I ordered the manual on CD from this site. Supposed to be FORD's manual. Know anything about it?
New User
Joined: Jan 2008
Posts: 0
Likes: 24
The horn relay is attached either to the to the dash brace behind the instrument cluster or just near the wiper switch.
With Cruise > the non-cruise horn circuit is changed by a harness change.
The former horn power now goes to the cruise buttons & the Horn actuates with a Ground out.
The only way to trouble-shoot this problem is to get in behind the cluster and check for power or Short out in the harness.
but first......unplug the steering column harness connector & do some contiuity tests with each wire.
The Ford manual goes into Cruise control trouble-shooting imore than any other manual.
Blown fuses & Fusible links are usually caused by direct Shorts.
With Cruise > the non-cruise horn circuit is changed by a harness change.
The former horn power now goes to the cruise buttons & the Horn actuates with a Ground out.
The only way to trouble-shoot this problem is to get in behind the cluster and check for power or Short out in the harness.
but first......unplug the steering column harness connector & do some contiuity tests with each wire.
The Ford manual goes into Cruise control trouble-shooting imore than any other manual.
Blown fuses & Fusible links are usually caused by direct Shorts.
Senior User
Joined: Mar 2002
Posts: 490
Likes: 1
From: Phx, AZ
the horn relay is behind the speedometer on the left side of the firewall just below the cruise control module box.
Trending Topics
New User
Joined: Oct 2003
Posts: 23
Likes: 0
From: Massachusetts
He has no power anywhere so I would suspect a link over a fuse. If a link is found th be bad I would put a test light between the battery and the circuit that the link feeds. If the light is on you have a constant short. Pull fuses out one at a time until the light goes out. This will be the shorted circuit. If the light only lights when the horn bar is pressed, disconnect the horn and the cruise module, if the light still lights when the bar is pressed, have a friend hold the horn bar and shake twist harness to see if you can find an area that makes the light flicker. Maybe a piece of chassis has cut the harness somewhere.
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
Rezvani's Latest Post-Apocalytic Monster Is a Ford F-150 Raptor Underneath
Verdad Gallardo
Top 10 Most Expensive Ford Trucks Ever Sold on Bring a Trailer
Joe Kucinski
2027 Ford Super Duty Buyer's Guide (Every Model, Engine, & Package)
Brett Foote
Top 10 Ford Truck Tragedies
Joe Kucinski
AEV FXL Super Duty - the Super Duty Raptor Ford Doesn't Make
Brett Foote
Lobo Vs Lobo: Proof the F-150 Lobo Should Be Even Lower!
Michael S. Palmer
Ford's 2001 Explorer Sportsman Concept Looks For a New Home
Verdad Gallardo
10 Best Ford Truck Engines We Miss the Most!
Joe Kucinski
2026 Shelby F-150 Off-Road: Better Than a Raptor R?
Brett Foote
Thread
Thread Starter
Forum
Replies
Last Post
canadianfordman
1980 - 1986 Bullnose F100, F150 & Larger F-Series Trucks
8
Oct 22, 2002 07:20 AM
