Notices
1987 - 1996 F150 & Larger F-Series Trucks 1987 - 1996 Ford F-150, F-250, F-350 and larger pickups - including the 1997 heavy-duty F250/F350+ trucks

Electrical issue.

Thread Tools
 
Search this Thread
 
Old Jan 30, 2017 | 10:22 PM
  #16  
Building_Fords's Avatar
Building_Fords
Thread Starter
|
Senior User
Joined: Aug 2014
Posts: 185
Likes: 0
From: Olanta, PA
Thanks ArdWrknTrk, Yes, i mispoke, I always think of the black wire going down to the Starter as a Negative... I replaced the Alternator, then I fixed the witing, but there was one "Hard" drive in between. I am getting almost nothing on the Gr/Red wire, I bought the new connections and replaced the wire all the way to the old connectuin, (right behind the battery) I am wondering if the connection itself is bad. I will check that tomorrow or Wednesday. Which Fuse is the one you show in the diagram? I will check that as well. if the wiring is replaced, it must be the new ALT.... since the first thing it needs to do is get power to that wire... I'll let you know what I find.
 
Reply
Old Jan 31, 2017 | 09:00 AM
  #17  
rla2005's Avatar
rla2005
Fleet Owner
20 Year Member
Community Builder
Liked
Community Favorite
Joined: Oct 2005
Posts: 20,789
Likes: 1,753
From: Kentucky
Until you get power on the Light Green/Red wire the alternator is an expensive idler pulley.

As noted in the basic diagram there is fused power running to the charge lamp. There is SUPPOSED to be a parallel resistor to allow current flow if that bulb is open. Many times that resistor is missing or has poor connection so when the bulb is open there is no power to turn the alternator on.

I do not have a detailed charging circuit diagram for anything before 1992, but you should have a gray fuse link off the charge wires that connect to the positive battery side of the starter solenoid. The diagram above shows two Black/Orange wires leading to the fuse link.
 
Reply
Old Jan 31, 2017 | 10:01 AM
  #18  
Building_Fords's Avatar
Building_Fords
Thread Starter
|
Senior User
Joined: Aug 2014
Posts: 185
Likes: 0
From: Olanta, PA
OK, so I am looking for power going TO the Alternator, not coming from it on the GR/Red wire. I was checking power coming from the ALT. Yes, The Fused Link coming from the ALT. has three lines running into it, 2 x Black/Orange, and 1 Yellow, the Pigtail (Black/White) only runs from one connection to the other on the back of the ALT, and the GR/Red runs to it's own connection near the battery. I will check fuses in the fuse block under the dash for any blown fuses. The Starter side of the Starter Relay only has the starter line on it. everything else is on the "Hot" side.
So, if I am following you correctly, and I have a good 20 amp fuse, I should have power going to the ALT via the GR/RED WIRE. if there is power there then it's my Alternator. If The GR/Red is dead and the fuses are all good... I need to track that line to find a break/short.
 
Reply
Old Jan 31, 2017 | 11:11 AM
  #19  
rla2005's Avatar
rla2005
Fleet Owner
20 Year Member
Community Builder
Liked
Community Favorite
Joined: Oct 2005
Posts: 20,789
Likes: 1,753
From: Kentucky
Originally Posted by Building_Fords
So, if I am following you correctly, and I have a good 20 amp fuse, I should have power going to the ALT via the GR/RED WIRE.
Correct


Originally Posted by Building_Fords
if there is power there then it's my Alternator.
Most likely, yes


Originally Posted by Building_Fords
If The GR/Red is dead and the fuses are all good... I need to track that line to find a break/short.
Correct
 
Reply
Old Jan 31, 2017 | 12:35 PM
  #20  
ArdWrknTrk's Avatar
ArdWrknTrk
pedant
Joined: Jan 2008
Posts: 23,576
Likes: 40
From: EXTREME southwest CT
Club FTE Silver Member

I have an '87 evtm Gary.
There may be some differences from the 1986.

I'll try to get a picture from my (bricknose) manual when I get off work.
What year and engine is your truck buildingfords.?
 
Reply
Old Jan 31, 2017 | 05:15 PM
  #21  
ArdWrknTrk's Avatar
ArdWrknTrk
pedant
Joined: Jan 2008
Posts: 23,576
Likes: 40
From: EXTREME southwest CT
Club FTE Silver Member

No reply as to what engine so I'll post both pages.

1G with AC, 2G without
See the 904 lt grn/red wire in the middle?
This is the other page, facing the previous one...
Here we are at p 27
Lt grn/ red wire from middle of page to charge indicator, and red/lt grn back to ignition switch.
(For duraspark)

For eec (4.9&5.0)
Hope this helps...
 
Reply
Old Jan 31, 2017 | 05:19 PM
  #22  
ArdWrknTrk's Avatar
ArdWrknTrk
pedant
Joined: Jan 2008
Posts: 23,576
Likes: 40
From: EXTREME southwest CT
Club FTE Silver Member

... I have no idea why only the last pic came out sideways.
 
Reply
Old Jan 31, 2017 | 06:11 PM
  #23  
rla2005's Avatar
rla2005
Fleet Owner
20 Year Member
Community Builder
Liked
Community Favorite
Joined: Oct 2005
Posts: 20,789
Likes: 1,753
From: Kentucky
Originally Posted by ArdWrknTrk
... I have no idea why only the last pic came out sideways.
PEBKAC.....
 
Reply
FTE Stories

Ford Trucks for Ford Truck Enthusiasts

story-0

This Hennessey Takes the Expedition Tremor's Off-Roading Capability to the Next Level

 Verdad Gallardo
story-1

Top 10 Fords at 2026 Carlisle Ford Nationals

 Joe Kucinski
story-2

3 Best / 3 Worst Parts of Modern Ford Ownership

 Brett Foote
story-3

10 Amazing Upgrades That Solve Common Ford Truck Owner Headaches

 Pouria Savadkouei
story-4

Every 2026 Ford Engine Explained

 Brett Foote
story-5

10 Ugly Ford Trucks That We Still Kinda Love

 Joe Kucinski
story-6

10 Things Every Truck Owner NEEDS (2026 Edition)

 Michael S. Palmer
story-7

Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath

 Verdad Gallardo
story-8

Top 10 Most Expensive Ford Trucks Ever Sold on Bring a Trailer

 Joe Kucinski
story-9

2027 Ford Super Duty Buyer's Guide (Every Model, Engine, & Package)

 Brett Foote
Old Jan 31, 2017 | 06:19 PM
  #24  
ArdWrknTrk's Avatar
ArdWrknTrk
pedant
Joined: Jan 2008
Posts: 23,576
Likes: 40
From: EXTREME southwest CT
Club FTE Silver Member

Originally Posted by rla2005
PEBKAC.....
May well could be.

I guess what I'm trying to point out is that there is no fuse for '87.
But I'm sure there is a fusible link at the hot post of the starter relay.
​​​​​​​Check for continuity there and check that the cluster plugs are clean and completely seated.
 
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
oldford78
1973 - 1979 F-100 & Larger F-Series Trucks
3
Apr 2, 2015 11:00 AM
rudedawg
1987 - 1996 F150 & Larger F-Series Trucks
10
Dec 7, 2009 06:14 PM
John311t
1999 - 2003 7.3L Power Stroke Diesel
17
Aug 24, 2007 07:04 PM
jxer00
Small Block V8 (221, 260, 289, 5.0/302, 5.8/351W)
3
Sep 28, 2005 10:04 AM
flyhound
Electrical Systems/Wiring
13
Jul 15, 2005 06:46 PM




All times are GMT -5. The time now is 04:21 PM.

story-0
This Hennessey Takes the Expedition Tremor's Off-Roading Capability to the Next Level

Slideshow: The VelociRaptor Expedition gains a lift, upgraded suspension, Brembo brakes, and trail-ready equipment while retaining the stock 440-horsepower EcoBoost V6.

By Verdad Gallardo | 2026-06-12 11:01:55


VIEW MORE
story-1
Top 10 Fords at 2026 Carlisle Ford Nationals

Slideshow: Top 10 Fords at 2026 Ford Nationals

By Joe Kucinski | 2026-06-09 11:10:08


VIEW MORE
story-2
3 Best / 3 Worst Parts of Modern Ford Ownership

Based on years of owning multiple modern Ford products.

By Brett Foote | 2026-06-09 10:53:36


VIEW MORE
story-3
10 Amazing Upgrades That Solve Common Ford Truck Owner Headaches

SPONSORED: From muddy boots to rain-soaked cargo, these upgrades address some of the most common frustrations Ford truck owners face every day.

By Pouria Savadkouei | 2026-06-08 18:50:34


VIEW MORE
story-4
Every 2026 Ford Engine Explained

Here's everything you need to know about every Ford engine available for the 2026 model year.

By Brett Foote | 2026-06-05 12:58:01


VIEW MORE
story-5
10 Ugly Ford Trucks That We Still Kinda Love

Slideshow: 10 ugly Ford trucks that we still kinda love.

By Joe Kucinski | 2026-06-03 09:51:16


VIEW MORE
story-6
10 Things Every Truck Owner NEEDS (2026 Edition)

Slideshow: the best gifts for dads & grads

By Michael S. Palmer | 2026-06-03 15:43:58


VIEW MORE
story-7
Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath

Slideshow: Called the Fortress, the 850-horsepower pickup combines Raptor underpinnings with military-inspired features, survival equipment, and a starting price of $285,000.

By Verdad Gallardo | 2026-06-03 11:38:36


VIEW MORE
story-8
Top 10 Most Expensive Ford Trucks Ever Sold on Bring a Trailer

Slideshow: 10 most expensive Ford trucks ever sold on Bring a Trailer.

By Joe Kucinski | 2026-05-27 16:24:34


VIEW MORE
story-9
2027 Ford Super Duty Buyer's Guide (Every Model, Engine, & Package)

Here's everything that has changed for the latest model year.

By Brett Foote | 2026-05-27 16:17:28


VIEW MORE