Dash indicator lights
Thread Starter
|
Freshman User
Joined: Jul 2012
Posts: 42
Likes: 0
Dash indicator lights
Working on a 1978 F100. Replaced flasher and all dash light bulbs. Turn signals work, but the left dash indicator light does not and the right one does. I know that one of the bulbs in the back of the instrument cluster specifically is for the left indicator, but it has been replaced and everything works and lights up. I'm at an end, any help greatly appreciated!
Posting Guru
Joined: Jul 2012
Posts: 1,958
Likes: 2
From: Georgia
Working on a 1978 F100. Replaced flasher and all dash light bulbs. Turn signals work, but the left dash indicator light does not and the right one does. I know that one of the bulbs in the back of the instrument cluster specifically is for the left indicator, but it has been replaced and everything works and lights up. I'm at an end, any help greatly appreciated!
Posting Guru
Joined: Jul 2012
Posts: 1,958
Likes: 2
From: Georgia
Does the it light up when you turn the flashers on? Are your fuses good? If not, corrosion and grounding is almost always the problem. Make sure all the connections have no corrosion and check grounding. If it's not that check the bulb socket.
Posting Guru
Joined: Jul 2012
Posts: 1,958
Likes: 2
From: Georgia
Thread Starter
|
Freshman User
Joined: Jul 2012
Posts: 42
Likes: 0
It does not light up when I turn the turn signal, but the right one does. This is what is confusing me. Replaced the bulb and the socket seems fine. Does each individual dash bulb have its own ground or just one for the whole cluster? Again everything else works fine including the right signal indicator.
Posting Guru
Joined: Jul 2012
Posts: 1,958
Likes: 2
From: Georgia
Follow the harness from the cluster down to the kick panel, and across toward the radio. You should find several black wires screwed to the dash structure & the bottom of the A-pillar.
I understand about the right one working and the left one not working but does both indicators work when you turn the flasher/hazard lights on?
I understand about the right one working and the left one not working but does both indicators work when you turn the flasher/hazard lights on?
Trending Topics
Thread Starter
|
Freshman User
Joined: Jul 2012
Posts: 42
Likes: 0
Not sure about the hazards, will check tomorrow morning and get back with you. I appreciate your help 460 Ford Man!
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
10 Best Ford Truck Engines We Miss the Most!
Joe Kucinski
2026 Shelby F-150 Off-Road: Better Than a Raptor R?
Brett Foote
2027 Super Duty Carhartt Package First Look: 12 Things You NEED to Know!
Michael S. Palmer
10 Most Surprising 2026 Ford Truck Features!
Joe Kucinski
Top 10 Ford Trucks Coming to Mecum Indy 2026
Brett Foote
5 Best / 5 Worst Ford Truck Wheels of All Time
Joe Kucinski
Ford Super Duty: 5 Things Owners LOVE, 5 Things They LOATHE!
Joe Kucinski
Every 2026 Ford Truck Engine RANKED from WORST to FIRST!
Michael S. Palmer
The Best F-150 Deal of Every Trim Level (XL through Raptor)
Joe Kucinski
Post Fiend
Joined: Jul 2004
Posts: 8,786
Likes: 28
From: Northern California
It does not light up when I turn the turn signal, but the right one does. This is what is confusing me. Replaced the bulb and the socket seems fine. Does each individual dash bulb have its own ground or just one for the whole cluster? Again everything else works fine including the right signal indicator.
The dash bulbs share a ground through the printed circut.
It could be one of Four things IF all the outside turn signals work.
1: Bad Bulb or socket in the cluster.
Hope this helps...
Double check these. Pretty easy with a Multi meter set to ohms.
2: Bad wiring to the cluster or coroded wire terminals at the connectors.Check for power at the Green/White stripe wire for left side, and the White/Blue stripe wire for the right side at the cluster connector. If you have power to both of these, with the ignition switch in run, with the turn signal switch on in it's respective mode, LEFT /RIGHT. Then the cluster is at fault somewhere.
3: Defective Printed Circut.Check for tarnished copper at the cluster connector points and at the bulb socket connections. You can clean the oxidation with a pencil eraser. Lightly rub the eraser on the copper until it becomes bright. Don't use excessive force as the printed circut is easily damaged. Check for missing copper around the connections as well.
4: Cluster Rot SyndromeCheck around the hole where the bulb socket attaches to the cluster plastic. If the plastic is crumbly, the bulb socket cannot make a good tight connection with the printed circut. The whole cluster plastic backing will need to be replaced.
Thread Starter
|
Freshman User
Joined: Jul 2012
Posts: 42
Likes: 0
So, after checking the hazards I have concluded this: when engaging the hazards all lights front and back blink properly, but the left dash indicator does not blink (right one does work). Now when using the turn signals this is the deal: right one works front, back and dash indicator blinks, left one blinks in the back but not the front or on the dash indicator. Sorry this is long and convoluted, but it's driving me crazy and I have no real electronics skill or know how (i.e. testing wires and circuit boards). Thanks again for you all's input!
Post Fiend
Joined: Jul 2004
Posts: 8,786
Likes: 28
From: Northern California
All outside lights front and back flash, but the left dash indicator does not.
Check the Left front again and confirm that it is working with hazards on.
Now when using the turn signals this is the deal: right one works front, back and dash indicator blinks, left one blinks in the back but not the front or on the dash indicator. Sorry this is long and convoluted, but it's driving me crazy and I have no real electronics skill or know how (i.e. testing wires and circuit boards). Thanks again for you all's input!
1: Defective turn signal switch:
4: Defective grounds in left front. Check and clean all ground wires along the left front fender.
To test wires and circuts for a novice, a Test light is a good investment. So is a multimeter. Both should come with directions in how to use them.The Front and back turn signals are seperated inside the switch. They are only connected when the hazards are engaged. The indicators in the dash are connected to the front circut only. If the front turn signal on the left works with the hazards, the dash indicator should as well as they are on the same circut. Since they are not, you might have more than one issue.
Check for power at the Green/White stripe wire at the horseshoe connector at the bottom of the column for power with the turn signal on. If there is power there, you will need to correct a wiring issue. If no power, you will have to go up inside the column and check the switch itself.
2: Defecive wiring between turnsignal switch and cluster and/or front left turn signal lamp.Check for power at the Green/White stripe wire at the horseshoe connector at the bottom of the column for power with the turn signal on. If there is power there, you will need to correct a wiring issue. If no power, you will have to go up inside the column and check the switch itself.
Check the Green/White stripe wire at the cluster connector for power. Then check the Green/White Stripe (or white/blue stripe as sometimes ford used the same front turn signal harness for both sides) wire at the left front turn signal for power. If you have power to both those connectors then look for a ground fault, or check to see if someone replaced a normal incandecent bulb with a LED.
Also check the cluster for cluster rot syndrome as I described earlier, or for a damaged printed circut. You might have more than one issue.
3: Defective Lamp socket left front. Loss of ground.Also check the cluster for cluster rot syndrome as I described earlier, or for a damaged printed circut. You might have more than one issue.
4: Defective grounds in left front. Check and clean all ground wires along the left front fender.
The test light is the easiest, as you hook one end to the wire you want to test, and ground the other end. If the bulb in the tester lights, then the circut has power. etc...
Elder User
Joined: Sep 2010
Posts: 604
Likes: 4
From: Antioch, CA
check your left front socket, make sure its grounded properly and the bulbs good. I had a similar problem, usually bad sockets in the front will cause turn signal indicator light problems.
your going to need a multimeter, I would invest in one. youll end up using it all the time.
your going to need a multimeter, I would invest in one. youll end up using it all the time.
Thread
Thread Starter
Forum
Replies
Last Post
scottlane
1973 - 1979 F-100 & Larger F-Series Trucks
21
Oct 4, 2005 08:27 AM