No dash lights
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From: abilene kansas
No dash lights
The instrument panel lights on My truck are not working. The fuse for the instrument panel lights is good. None of the lights work. The dome light comes on when I rotate the **** fully to the left. Also,when I turn the headlights on, the right turn signal indicator in the dash lights up. What should I look at now? (And no, I don't have the light switch **** all the way to the right)
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From: Denver Metro Area, CO
For the right turn-signal indicator, inspect your front-right turn signal bulb & socket.
If the 5A fuse for the instrument lamps is good... do you have a meter or test lamp? Test for power at the fuse with the headlamp switch pulled out halfway and the **** turn to the left (but not far enough to turn on the dome lamp).
Do you have an aftermarket radio installed by chance? And, did you ground out the light-blue/red-stripe wire by chance? That's the dimmable dash backlighting circuit that lights the gauge cluster, instrument controls, HVAC controls and ashtrays (if equipped with optional Convenience Lighting Group or some such).
If the 5A fuse for the instrument lamps is good... do you have a meter or test lamp? Test for power at the fuse with the headlamp switch pulled out halfway and the **** turn to the left (but not far enough to turn on the dome lamp).
Do you have an aftermarket radio installed by chance? And, did you ground out the light-blue/red-stripe wire by chance? That's the dimmable dash backlighting circuit that lights the gauge cluster, instrument controls, HVAC controls and ashtrays (if equipped with optional Convenience Lighting Group or some such).
FTE Legend
Joined: Jul 2010
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From: Northeast, OK
The dash lights are powered through a rheostat that is on the headlight switch. If the fuse is good and you have no dash lights I'd bet that the rheostat is burned through or very dirty. Try turning the **** back and forth several times with the switch pulled out to the first position, and watch the dash lights as you do that. If you see them flicker any then it sounds like the rheostat is dirty. If nothing happens it may be burned.
The switch is a bear to get out given the contortions you have to go through to get to the connector. And, you have to remove either the **** or the **** and shaft to get the nut off. But, if you take it out you'll see the rheostat on the end of the switch nearest the ****. Look for burn marks.
The switch is a bear to get out given the contortions you have to go through to get to the connector. And, you have to remove either the **** or the **** and shaft to get the nut off. But, if you take it out you'll see the rheostat on the end of the switch nearest the ****. Look for burn marks.
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Posting Guru
Joined: Dec 2012
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From: abilene kansas
For the right turn-signal indicator, inspect your front-right turn signal bulb & socket.
If the 5A fuse for the instrument lamps is good... do you have a meter or test lamp? Test for power at the fuse with the headlamp switch pulled out halfway and the **** turn to the left (but not far enough to turn on the dome lamp).
Do you have an aftermarket radio installed by chance? And, did you ground out the light-blue/red-stripe wire by chance? That's the dimmable dash backlighting circuit that lights the gauge cluster, instrument controls, HVAC controls and ashtrays (if equipped with optional Convenience Lighting Group or some such).
If the 5A fuse for the instrument lamps is good... do you have a meter or test lamp? Test for power at the fuse with the headlamp switch pulled out halfway and the **** turn to the left (but not far enough to turn on the dome lamp).
Do you have an aftermarket radio installed by chance? And, did you ground out the light-blue/red-stripe wire by chance? That's the dimmable dash backlighting circuit that lights the gauge cluster, instrument controls, HVAC controls and ashtrays (if equipped with optional Convenience Lighting Group or some such).
The dash lights are powered through a rheostat that is on the headlight switch. If the fuse is good and you have no dash lights I'd bet that the rheostat is burned through or very dirty. Try turning the **** back and forth several times with the switch pulled out to the first position, and watch the dash lights as you do that. If you see them flicker any then it sounds like the rheostat is dirty. If nothing happens it may be burned.
The switch is a bear to get out given the contortions you have to go through to get to the connector. And, you have to remove either the **** or the **** and shaft to get the nut off. But, if you take it out you'll see the rheostat on the end of the switch nearest the ****. Look for burn marks.
The switch is a bear to get out given the contortions you have to go through to get to the connector. And, you have to remove either the **** or the **** and shaft to get the nut off. But, if you take it out you'll see the rheostat on the end of the switch nearest the ****. Look for burn marks.
FTE Legend
Joined: Jul 2010
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From: Northeast, OK
I know the felling on the dash pad. Do you have working lights in the heater control panel? They are also fed by the rheostat, so if they are working it isn't that.
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From: Virginia
You need to look at the right front socket for the light under the headlight, because you have a bad ground out there. When you turn the headlights on, power is going to the running light filament, and instead of going to ground it's going backwards up the turnsignal wire and is finding it's ground through the dash indicator light. That's why that light is coming on. I bet your turnsignal doesn't work on that side with the headlights on does it?
A good test whas also mentioned in the same previous post, put your meter on the fuse for the instrument lights with the headlight switch on, and see if you have voltage at the fuse. The reason for this is because this fuse is AFTER the headlight switch dimmer control. Having no voltage on this fuse will verify you do have a problem at the headlight switch.
P.S. Your running lights outside the truck do work don't they? If that fuse is bad, the instrument lights won't work either. The instrument lights are fed from the instrument light fuse, which is fed from the headlight switch rheostat, which is fed from the running light feed, which is fed from the running light fuse.
A good test whas also mentioned in the same previous post, put your meter on the fuse for the instrument lights with the headlight switch on, and see if you have voltage at the fuse. The reason for this is because this fuse is AFTER the headlight switch dimmer control. Having no voltage on this fuse will verify you do have a problem at the headlight switch.
P.S. Your running lights outside the truck do work don't they? If that fuse is bad, the instrument lights won't work either. The instrument lights are fed from the instrument light fuse, which is fed from the headlight switch rheostat, which is fed from the running light feed, which is fed from the running light fuse.
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Joined: Jul 2004
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From: Northern California
P.S. Your running lights outside the truck do work don't they? If that fuse is bad, the instrument lights won't work either. The instrument lights are fed from the instrument light fuse, which is fed from the headlight switch rheostat, which is fed from the running light feed, which is fed from the running light fuse.
Unfortunately it's not correct for the 1980 model.
The Running Lamps, and the Horn are fed off the Headlight switches main power feed, and protected by the headlamp switches circut breaker.
There is no running lamp or horn fuse on the 1980 as they get their power from the same feed as the Headlamps. 1980 only.
So this may seem strange to say, but does the horn work? If the horn and the running lights work, then the circut breaker in that part of the Headlamp switch is ok, unless sounding the horn makes the headlamps or running lights flash. If the horn and running lights don't work, along with the instrument lights, check the connector at the headlamp switch for faults, and replace the headlamp switch, especially if the headlamps work. If the headlamps don't work, then check the power feed to the headlamp switch for a fault, and check for other wiring faults before replacing the switch.
The Rheostat on the switch may still be faulty, or there may be an internal fault in the switch still if the instrument cluster lights do not function with a good fuse.
Also the 1980 headlamp switch works with the 1980 only. A 1981-1986 headlamp switch will not work and will cause problems even though they look similar and will plug in. If everything checks out, make sure someone didn't install a 1981-1986 switch by mistake.
Check the aftermarket radio wiring as Chris (CTUBUTIS) explained earlier. It's a comon problem for people to mistake the factory radio dial illumination circut for the radio ground wire, because the power wire, and the radio ilumination wire are in the same plug. The factory radio does not have a ground wire, and grounds directly to it's case when installed into the dash.
good luck.
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Posting Guru
Joined: Dec 2012
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From: abilene kansas
This is correct for 1981-1986.
Unfortunately it's not correct for the 1980 model.
The Running Lamps, and the Horn are fed off the Headlight switches main power feed, and protected by the headlamp switches circut breaker.
There is no running lamp or horn fuse on the 1980 as they get their power from the same feed as the Headlamps. 1980 only.
So this may seem strange to say, but does the horn work? If the horn and the running lights work, then the circut breaker in that part of the Headlamp switch is ok, unless sounding the horn makes the headlamps or running lights flash. If the horn and running lights don't work, along with the instrument lights, check the connector at the headlamp switch for faults, and replace the headlamp switch, especially if the headlamps work. If the headlamps don't work, then check the power feed to the headlamp switch for a fault, and check for other wiring faults before replacing the switch.
The Rheostat on the switch may still be faulty, or there may be an internal fault in the switch still if the instrument cluster lights do not function with a good fuse.
Also the 1980 headlamp switch works with the 1980 only. A 1981-1986 headlamp switch will not work and will cause problems even though they look similar and will plug in. If everything checks out, make sure someone didn't install a 1981-1986 switch by mistake.
Check the aftermarket radio wiring as Chris (CTUBUTIS) explained earlier. It's a comon problem for people to mistake the factory radio dial illumination circut for the radio ground wire, because the power wire, and the radio ilumination wire are in the same plug. The factory radio does not have a ground wire, and grounds directly to it's case when installed into the dash.
good luck.
Unfortunately it's not correct for the 1980 model.
The Running Lamps, and the Horn are fed off the Headlight switches main power feed, and protected by the headlamp switches circut breaker.
There is no running lamp or horn fuse on the 1980 as they get their power from the same feed as the Headlamps. 1980 only.
So this may seem strange to say, but does the horn work? If the horn and the running lights work, then the circut breaker in that part of the Headlamp switch is ok, unless sounding the horn makes the headlamps or running lights flash. If the horn and running lights don't work, along with the instrument lights, check the connector at the headlamp switch for faults, and replace the headlamp switch, especially if the headlamps work. If the headlamps don't work, then check the power feed to the headlamp switch for a fault, and check for other wiring faults before replacing the switch.
The Rheostat on the switch may still be faulty, or there may be an internal fault in the switch still if the instrument cluster lights do not function with a good fuse.
Also the 1980 headlamp switch works with the 1980 only. A 1981-1986 headlamp switch will not work and will cause problems even though they look similar and will plug in. If everything checks out, make sure someone didn't install a 1981-1986 switch by mistake.
Check the aftermarket radio wiring as Chris (CTUBUTIS) explained earlier. It's a comon problem for people to mistake the factory radio dial illumination circut for the radio ground wire, because the power wire, and the radio ilumination wire are in the same plug. The factory radio does not have a ground wire, and grounds directly to it's case when installed into the dash.
good luck.
FTE Legend
Joined: Jul 2010
Posts: 32,874
Likes: 44
From: Northeast, OK
The flickering lights as you rotate the **** indicates a dirty or bad rheostat.
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Posting Guru
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From: abilene kansas
Replaced headlight switch , and that fixed the dash light problem. I still have the issue with the RH turn indicator coming on when headlights are on, front grounds were cleaned today. So more electrical tracing is coming up
FTE Legend
Joined: Jul 2010
Posts: 32,874
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From: Northeast, OK
One step at a time. Many of these trucks have several layers of problems and fixing them is like pealing an onion. And, when working on grounds it takes "fixing" several usually before you get the right one as they can cause strange symptoms.
More Turbo
Joined: Apr 2018
Posts: 699
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From: pine city washington
No dash lights
Bought an 88 f150 fixed the bad starter drove it to my son inn laws house in the daylight.sat there for a week or so then had to move them and it at night that is when I found out no light at all it was a scary drive don't know my speed or anything. God was watching over me. This was in the middle of wheat country with no street lights.so much fun. I think it is a bad switch. The truck is parked for now. While I recover from heart surgery .