Notices
1973 - 1979 F-100 & Larger F-Series Trucks Discuss the Dentsides Ford Truck
Sponsored by:
Sponsored by: Moser

Request for help with electrical problem

Thread Tools
 
Search this Thread
 
Old Jan 14, 2019 | 03:11 AM
  #1  
holger100's Avatar
holger100
Thread Starter
|
New User
Joined: Jan 2019
Posts: 1
Likes: 0
Request for help with electrical problem

Hello,
I hope someone can help me.

I'm setting myself up for a Ford F-100 (1978, V8 5.0L, 302cui) and am currently standing with a big question mark in my face.

My problem: The instrument lighting is working only partially.
The light or bulbs for safety belts, handbrake, high beam, turn signals on the left and right, windscreen wipers and driving lights and the lighting from the heating unit work.
It does not work: Oil gauge lighting, fuel gauge, speedometer, battery gauge and engine temperature gauge.

What I could exclude:
- All bulbs of the instrument unit replaced by new ones (also versions cleaned)
- fuse works (it is fine and otherwise the other lights would not go)
- Plug in the unit (on the back) seems to be in order and has also locked in

Did I miss something? Could the "board" (cluster at the back) at the back have a defect? Or is there a special trick?

Already thank you for accepting my problem.
 
Reply
Old Jan 14, 2019 | 12:56 PM
  #2  
meangreen92's Avatar
meangreen92
Logistics Pro
20 Year Member
Liked
Loved
Community Favorite
Joined: Jul 2005
Posts: 4,217
Likes: 154
The back of the cluster can crumble, causing the bulb holders to not go in tightly, and losing contact.

Your light switch could be the problem too. And don't forget that the **** can be turned to change the brightness, so it might be all the way at dim, if you're lucky.

Are your heater controls and the indicators for the headlight and wiper controls lighting up? They're supposed to light up with the gauge lights.
 
Reply
Old Jan 14, 2019 | 01:42 PM
  #3  
NumberDummy's Avatar
NumberDummy
Ford Parts Specialist
Joined: Nov 2006
Posts: 88,826
Likes: 787
From: Simi Valley, CA
Club FTE Gold Member
Originally Posted by holger100
I'm setting myself up for a 1978 F-100 and am currently standing with a big question mark in my face. My problem:

The instrument lighting is working only partially. The light or bulbs for safety belts, handbrake, high beam, turn signals on the left and right, windscreen wipers and driving lights and the lighting from the heating unit work.

It does not work: Oil gauge lighting, fuel gauge, speedometer, battery gauge and engine temperature gauge.

What I could exclude:

All bulbs of the instrument unit replaced by new ones (also versions cleaned) / Fuse works (it is fine and otherwise the other lights would not go).

Plug in the unit (on the back) seems to be in order and has also locked in

Did I miss something? Does the "board" (cluster back) have a defect?
YES!
1975/79 F100/350; 1975/80 Econoline; 1978/79 Bronco:

The instrument cluster backs were made of a composition material that can TURN TO DUST before your very eyes!

1981: Ford came out with hard plastic cluster backs for Econolines. These were also the "service part replacements" for the POS composition cluster backs.

There are TWO types, both are obsolete. CARPENTER NOS OBSOLETE PARTS in Concord NC has both of them (dennis_carpenter.com .. 704-786-8139).

E1PZ-10848-A .. Hard Plastic Cluster Back - Use with Oil/Amp GAUGES / Obsolete

1981/91 Econoline / Retrofit: 1975/79 F100/350; 1975/80 Econoline; 1978/79 Bronco.
-------------------------------------------------------------------------------------------------
E1PZ-10848-B .. Hard Plastic Cluster Back - Use with Oil/Amp WARNING LAMPS / Obsolete

1981/86 Econoline / Retrofit: 1975/79 F100/350; 1975/80 Econoline; 1978/79 Bronco.
 
Reply
Old Jan 14, 2019 | 02:04 PM
  #4  
resonateur's Avatar
resonateur
Fleet Mechanic
Joined: Jan 2014
Posts: 1,946
Likes: 118
Holger:
If the above solutions don't correct your problem...this may be a stretch but I have a 66 that had a similar issue. I know the year is different, but Ford kept a lot of the wiring similar year to year. Check your ground at the ignition switch and your 12v power supply at the ignition switch. I think that the items you mention get either a ground or power through the switch, so make sure the ignition housing is getting ground and that the wires coming from the back of the ignition switch are all "hot". The items you mention all have a "common denominator".
 
Reply
Old Jan 14, 2019 | 02:54 PM
  #5  
John89's Avatar
John89
Fleet Mechanic
5 Year Member
Photogenic
Photoriffic
Shutterbug
Joined: Jul 2017
Posts: 1,448
Likes: 163
From: East Texas
You might also try cleaning the copper "runs" where the bulb holders make contact on the back of the printed circuit with a pencil eraser.
 
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
MWB323
1973 - 1979 F-100 & Larger F-Series Trucks
64
Nov 12, 2023 07:46 PM
jephwoyo
1973 - 1979 F-100 & Larger F-Series Trucks
6
Jan 23, 2017 12:34 PM
heykey4
1973 - 1979 F-100 & Larger F-Series Trucks
4
Feb 4, 2013 11:09 AM
Jay1978f250
1973 - 1979 F-100 & Larger F-Series Trucks
4
Jan 7, 2013 08:40 AM
19gator55
Electrical Systems/Wiring
2
Feb 17, 2004 06:03 PM




All times are GMT -5. The time now is 08:09 AM.

story-0
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-1
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-2
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-3
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-4
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-5
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-6
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-7
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-8
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
story-9
Top 10 Ford Truck Tragedies

Slideshow: Top 10 Ford truck tragedies.

By Joe Kucinski | 2026-05-18 19:34:33


VIEW MORE