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Discussion Starter #1
Hey! Looking forward to some help with this one, kinda stuck. My turn signal, ebrake, temp, gen, dome, headlight, tailight, reverse light and lights work perfectly.

My cluster speedo/fuel lights do not work. I have a 4A fuse installed in the "inst" slot and as soon as I pull the headlight knob out, the fuse blows.

To troubleshoot, I confirmed all the bulbs work and replaced the light switch but no difference.

If I disconnect the instrument cluster completely, the fuse still blows when I pull the light switch.

However, if I disconnect the cluster, and turn the light switch all the way down (completely dimmed) the fuse will NOT blow right away, but will once I turn the dimmer to about 2/3 power. If I do this with the cluster connected, it does the same thing but I still never see the lights.

I've also tried a 10A and 20A fuse but the result is the same. I blew about 7 fuses today trying to fix this.

I'm getting just over 12.5v at the inst. fuse.

My next thought is the fuse box connector for the "inst." fuse is probably rusted out but I didn't want to start monkeying around with it if it wasn't a likely fix. Bad fuse connector or faulty replacement light switch maybe?

Thanks,

Ian

p.s. I have a multimeter and I'm not affraid to use it but I don't know what/where to test.
 

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You have a short circuit - somewhere the hot is touching ground in that circuit.. The challenge of course is finding exactly where w/o going through a thousand fuses. Sometimes it can be as simple as a bulb with an internal short - if you're lucky. A good place to start would to pull all of the bulbs and see if the fuse blows with them all out. If not, replace one, test, add another, test etc.

oops - see that the fuse blows with the cluster disconnected. You'll have to trace the wire from the h/l switch, through the fuse box and to the cluster to see if you can find a pinched wire or something similar
 

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Discussion Starter #3 (Edited)
You have a short circuit - somewhere the hot is touching ground in that circuit.. The challenge of course is finding exactly where w/o going through a thousand fuses. Sometimes it can be as simple as a bulb with an internal short - if you're lucky. A good place to start would to pull all of the bulbs and see if the fuse blows with them all out. If not, replace one, test, add another, test etc.

oops - see that the fuse blows with the cluster disconnected. You'll have to trace the wire from the h/l switch, through the fuse box and to the cluster to see if you can find a pinched wire or something similar
I was going through my wiring diagram and noticed the Gray wire that goes from the speedo light, gas light and the heater light. I also see the split off to the heater light is between the light switch and the cluster. I've done everything short of splitting the tape off the harness and I can't find the split. Can anyone confirm if the wire splits inside the harness or have I missed a junction box somewhere? Also, the wiring diagram (my assembly manual and the color one attached) shows the Gray wire go to a connector of some kind with orange and green wires. Where can I find that? Is it supposed to be the fuse box?



I haven't looked at the heater light at all. It's probably mangled after all the times I pulled the stereo to get it working. To be totally honest, it's been so long since I saw the heater light on I forgot it even had a light ;)

Thanks!
 

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Usually, two wires will be in the terminal and crimped together.
The diagram is drawn for clarity, does not resemble the real world.
The inst cluster lights are powered via the circuit broad on the cluster.
The cluster connector may have a double gray wire in one terminal to go to the heater and radio dial light.

You can always replace the fuse with a light bulb and continue troubleshooting.
The bulb lit will show a short - find the short or bad bulb - they do short internally.
When test bulb goes out, short gone. Saves fuses.

You can use the meter as an ammeter, set the meter to read current, and touch the fuse panel contacts. Only problem is the meter has a 10 amp fuse, so it will read for a very short time. The test light is the best trick.
 

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I was going through my wiring diagram and noticed the Gray wire that goes from the speedo light, gas light and the heater light. I also see the split off to the heater light is between the light switch and the cluster. I've done everything short of splitting the tape off the harness and I can't find the split. Can anyone confirm if the wire splits inside the harness or have I missed a junction box somewhere? Also, the wiring diagram (my assembly manual and the color one attached) shows the Gray wire go to a connector of some kind with orange and green wires. Where can I find that? Is it supposed to be the fuse box?



I haven't looked at the heater light at all. It's probably mangled after all the times I pulled the stereo to get it working. To be totally honest, it's been so long since I saw the heater light on I forgot it even had a light ;)

Thanks!
Ian...it sounds like you answered your own question. The speedo, fuel and heater control lights share the same "hot" wire. All the dash lights share the same ground. If you disturbed the htr light wire with all the radio removal repairs, you most certainly have that wire mangled. Pull the appropriate fuse and all bulbs in that circuit, remove a small amount of insulation from the "gray" wire and use the ohmmeter to check for continuity to ground...there should be none :thumbsup:
 

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Is this a 69 or 67?

The wiring diagram is for a 69 and Everett referred to a circuit board on the cluster which would indicate 67.

Either way you have a short.
 

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Ian, here is a few things to check. Check all the light bulb sockets in the dash panel. http://www.camarocentral.com/1967_1981_Camaro_Dash_Instrument_Gauge_Cluster_L_p/das-174b.htm. Also check the printed circuit board on the back of the dash panel. http://www.camarocentral.com/1967_1968_Dash_Cluster_Printed_Circuit_Board_p/das-169.htm Use the multimeter and start checking the wires plugged into the light switch. If you have a console the gray wire in the console is for lighting so be sure to check it.
 

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Discussion Starter #8
...You can always replace the fuse with a light bulb and continue troubleshooting. The bulb lit will show a short - find the short or bad bulb - they do short internally. When test bulb goes out, short gone. Saves fuses...
Thank you everyone for the quick replies. I obviously need to get back out there and start peeking and poking with the meter. Everett, as simple as it sounds, I can't seem to wrap my head around this bulb to fuse test light idea. Would I just connect a wire from the hot side of the fuse connector to one side of a dash bulb, and then a wire from the opposite connector to the other side of the bulb? Basically have the bulb complete the circuit? I would think I could get this but it escapes me at 5am.

I've been given a couple suggestions to check the dash bulbs and printed circuit, but wouldn't the fuse blowing with the cluster disconnected eliminate those bulbs and the printed circuit?

At this point, my issue is one or some of the following:
  1. Fuse box connectors are corroded/rusted;
  2. Wire is pinched or poorly split somewhere;
  3. New headlight switch is a dud;
  4. Wire connector to cluster is dirty/damaged; or
  5. Heater control bulb/wire/connector is damaged/blown.
I have a console but I've converted from column and only run the necessities so far (neutral safety & reverse lights). Once I get the dash figured out I will finish replicating the console harness and add it to the mix.

Oh yes, I understand the poor attempt at a color mapped wiring diagram was for a 69, but I'm pretty sure its mostly the same for my 67. I use my actual black and white assembly manual when I troubleshoot in the car.

Thanks again!
 

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You would take a plastic socket for an 1156, or any bulb, socket should be plastic and have two leads, and connect a lead onto one fuse tap, one side of the fuse socket, the other lead onto the other socket, and apply power.

If light lights, short is on the gray wire going from the fuse panel.

Fuse tap: yes they do have them for round glass fuses:
http://www.autozone.com/electrical-...ssories/dorman-fuse-and-accessories/6427_0_0/

The light bulb filament becomes the current limiting device is the circuit. The filament only allows X amount of current to flow - hence, the brightness of the filament.
The more current, the brighter the glow.
 

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I would check the radio light since it is not being used. Maybe theres no bulb in the socket and its shorting out. Same for the ash tray light and heater control light. All grey wires I believe. Also there used to be a light that lit up the prndl indicator in the collumn shift before you converted to floor shift.(if automatic). I think all of those run off that same circuit independent of the cluster.
 

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Discussion Starter #11
Alright, I think I understand the fuse tap test light concept. To be sure, and to help anyone else as slow as me, I took 5 to mock up a diagram of what you said. Please let me know if this is wrong in some way.

And you're right, I need to confirm the existence and condition of other grey wire lights, like the ashtray, heater, radio, glovebox and console.

Thanks guys!
 

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Yes, correct test light.
You could use a lower wattage bulb - same base, but smaller filament/globe.
 

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I've been given a couple suggestions to check the dash bulbs and printed circuit, but wouldn't the fuse blowing with the cluster disconnected eliminate those bulbs and the printed circuit?
Yes, you have eliminated any problem within the cluster by doing this.
At this point, my issue is one or some of the following:
  1. Fuse box connectors are corroded/rusted;
  2. Wire is pinched or poorly split somewhere;
  3. New headlight switch is a dud;
  4. Wire connector to cluster is dirty/damaged; or
  5. Heater control bulb/wire/connector is damaged/blown.
Numbers 1,3,4 Doubtful IMHO. Number 2 is it but where? Number 5 is a possibility as is the radio ground being connected to the gray wire at the radio causing a direct short. I've seen this often.
I have a console but I've converted from column and only run the necessities so far (neutral safety & reverse lights). Once I get the dash figured out I will finish replicating the console harness and add it to the mix.
Just be sure the gray wire in the console harness is not grounded some place near here.

Jeff
 

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Discussion Starter #14
Well, I finally had time to go out and peek and poke today. Made up a fuse test light out of my old brake light socket and bulb. Test light connected to the fuse box, and the light stayed on when I pulled the instrument cluster connector and stayed on when I disconnected the heater light. I was fairly puzzled so out of frustration I disconnected the headlight switch connector and then reached for the steering column connector when it occurred to me my 'center console conversion' started as a column shift and of course, the column had a light for the gear indicator. I pulled the steering column connector and sure enough, test light went off. I looked on top of the column and could easily see the bulb wire was touching/grounding against the inside of the socket. I removed the male connector from the grey wire inside the curved connector.

This issue was literally right in front of my face. Thanks for all your help guys.
 

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