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73-87 Chevy _ GMC Trucks => Electrical => Topic started by: FOOSE on July 05, 2013, 09:51:51 PM

Title: why do the lights on my gauges not turn off??
Post by: FOOSE on July 05, 2013, 09:51:51 PM
Hello,

I just put the gauge cluster back in my 1983 truck and the lights turned on right away and I noticed the headlight switch was on so I turned off the headlights and the gauges stayed on, the only way I can turn them off is by turning the switch all the way to the right (dimming the gauges till they are off).

Has anyone had this problem before? its really confusing me! all help will be much appreciated!

Thanks!
Title: Re: why do the lights on my gauges not turn off??
Post by: Irish_Alley on July 05, 2013, 11:22:14 PM
i would make sure your printed circuit board is in the right position. so they stay on even with the key off? i would look to see whats supposed to get constant power in your dash. only thing i can think of is the clock if you have one. this is the same dash you took out right?
Title: Re: why do the lights on my gauges not turn off??
Post by: FOOSE on July 06, 2013, 08:51:23 PM
Well the printed circuit is in the right position, the lights stay on with the ignition off, what do you mean the clock? it has a clock but there is a separate wiring harness that leads up to it. and yes the gauge cluster is the factory one.

I took the fuse out and put it back in and now the lights don't even turn on at all, not even with the switch. its a brand new switch too. the fuse is not blown cause I checked again. its really getting annoying if you know what I mean.
Title: Re: why do the lights on my gauges not turn off??
Post by: rich weyand on July 06, 2013, 09:34:37 PM
Have you checked the cab and engine grounds?
Title: Re: why do the lights on my gauges not turn off??
Post by: FOOSE on July 06, 2013, 09:41:51 PM
yes there's all new grounds on bare metal and everything else works good in the cab. i'm beginning to think I got a faulty headlight switch.
Title: Re: why do the lights on my gauges not turn off??
Post by: Irish_Alley on July 06, 2013, 11:00:08 PM
never messed with the clocks before thought they where on the same power with the dash. head light switch is the only other thing i can think of.
Title: Re: why do the lights on my gauges not turn off??
Post by: Captkaos on July 09, 2013, 10:31:06 PM
Either the switch is bad or you have a wire shorted or in the wrong spot.  Is this with the key out?
Title: Re: why do the lights on my gauges not turn off??
Post by: FOOSE on July 10, 2013, 12:40:59 PM
yeah the key is out, I tried the lights again yesterday and now nothing turns on! everything in the cab works still and when I turn the key over the gauges move too. so it's just the light that are having problems! >:(
Title: Re: why do the lights on my gauges not turn off??
Post by: Irish_Alley on July 10, 2013, 11:07:43 PM
replace the switch. its like $15. as much as i hate throwing parts at a truck this seams to be a likely cause
Title: Re: why do the lights on my gauges not turn off??
Post by: bd on July 11, 2013, 12:22:01 AM
FOOSE,

Using your test light, probe both sides of the instrument panel fuse with the running lamps OFF and then ON.  Describe what you find under both circumstances.
Title: Re: why do the lights on my gauges not turn off??
Post by: Irish_Alley on July 11, 2013, 03:30:06 AM
thanks bd i dont know why but my patience is low nowadays lol. need to be smacked back to reality
Title: Re: why do the lights on my gauges not turn off??
Post by: FOOSE on July 18, 2013, 09:53:08 PM
Sorry for the late reply guys!! but I ordered a new switch and still the same problem!

I also noticed that the headlight and taillight connectors by the firewall have power with the switch off and key out, the bottom terminals have power when I check with a test light, so if my headlights and taillights were connected would they be on too??

Bd, the fuse has power both sides with either the switch ON or OFF, the only way the gauge lights turn off is when I unplug the switch. I have not checked the fuse for power when I unplug the switch yet though.

Any other Ideas? grounds somewhere I don't know about?

Thanks for the help guys! much appreciated!
John
Title: Re: why do the lights on my gauges not turn off??
Post by: bd on July 19, 2013, 12:42:39 AM
Unplug the headlamp switch then probe the brown wire and then the dark green wire in the headlamp connector.  Describe what you find.
Title: Re: why do the lights on my gauges and park lights not turn off??
Post by: FOOSE on July 20, 2013, 09:30:24 PM
ok so I unplugged the switch and everything is off, I plug it back in and then only the brown wires have power! (park lamps) once I turn the switch on then I have power to the headlights. here's some pictures of which ones have power with the switch plugged in but turned off and key out.

The number 2 wire that goes to my gauges, it powers just the lights and that's the only one that has power going to it with the key off and switch plugged in, once I unplug the switch I lose power there too.
Title: Re: why do the lights on my gauges not turn off??
Post by: bd on July 20, 2013, 11:30:37 PM
Referring to your upper image, the headlamp switch is miswired.  The two orange wires (fused battery power for running and instrument lamps) are in the wrong cavity! 

Unplug the headlamp switch and look at the switch terminals.  Pin "3" (where the orange wires are presently connected) should be "blank" (that spot is reserved for cab roof lamps).  The orange pair rightfully connects to pin "5".  The brown wire (running lamps) connects to pin "4".  Dark green (which powers the instrument lamps fuse) connects to pin "2".  Move the orange wire pair to the correct cavity and, Voila!  Your lights will power correctly!
Title: Re: why do the lights on my gauges not turn off??
Post by: Irish_Alley on July 20, 2013, 11:57:47 PM
Love ^^^^^this^^^^^ guy
Title: Re: why do the lights on my gauges not turn off??
Post by: FOOSE on July 21, 2013, 02:37:30 AM

Wow Bd you are insane!! how did you know?? I found the problem right after I sent the last post cause I found an old truck behind my backyard and I cut the connector off and compared it to mine, that's when I saw the orange wire was wrong, not sure how it got there, but you picked it out in a blurry picture! that is awesome!!! 8)

Thanks for all your help! i'm glad its fixed now! Take care guys!  :D
Title: Re: why do the lights on my gauges not turn off??
Post by: winky on July 21, 2013, 12:47:37 PM
BD is the chuck Norris of headlight switches!