If the instrument cluster lights DON'T work but the horn DOES work then it's NOT the headlight switch.
Electrical question.
I have an electrical problem I’m trying to wrap my head around.
Dissasembled my dash to replace my gauge cluster, redo the radio, repaint, and then replace my heater core and wiring.
Swapped out the gauge cluster, and tested the lights with them all working. Then plugged back in the wiper switch and seated cluster as well as screwed in.
Went to check the cluster one last time and they lit up but then went dark.
Thought that may be the battery was low, so pulled it out and placed on a charger for two hours. Placed back in and the lights lit up and the wipers worked but then everything clicked off again.
I’m assuming there’s a short somewhere but not sure where to start. Does anyone have any suggestions? 
Dissasembled my dash to replace my gauge cluster, redo the radio, repaint, and then replace my heater core and wiring.
Swapped out the gauge cluster, and tested the lights with them all working. Then plugged back in the wiper switch and seated cluster as well as screwed in.
Went to check the cluster one last time and they lit up but then went dark.
Thought that may be the battery was low, so pulled it out and placed on a charger for two hours. Placed back in and the lights lit up and the wipers worked but then everything clicked off again.
I’m assuming there’s a short somewhere but not sure where to start. Does anyone have any suggestions? 
21 - 40 of 67 Posts
Hmmm. I’ll have to check that. Explain to me how that works?If the instrument cluster lights DON'T work but the horn DOES work then it's NOT the headlight switch.
So I pulled the cluster and made sure everything was seated and a good ground. So far everything is working.What Woodchuck is saying is that they are both powered by the same circuit breaker inside the light switch. But there is still a switch that could also be defective in "On" or "Park" (circled in yellow).
View attachment 865340
But what’s weird is if I pull the light switch to the first stop, the dash lights and the marker/fog lights light up. But if I pull to the second stop, the dash goes off and the headlights come on.
Is that normal?
No. The instrument cluster lights should stay on in both "Park" and "Head" mode. Make sure you have the correct headlight switch as some are "pinned" differently. It sounds like the cluster lights are getting power from the "park" feed. Are the parking lamps on with the headlamps?So I pulled the cluster and made sure everything was seated and a good ground. So far everything is working.
But what’s weird is if I pull the light switch to the first stop, the dash lights and the marker/fog lights light up. But if I pull to the second stop, the dash goes off and the headlights come on.
Is that normal?
No they are not. And neither are the taillights.No. The instrument cluster lights should stay on in both "Park" and "Head" mode. Make sure you have the correct headlight switch as some are "pinned" differently. It sounds like the cluster lights are getting power from the "park" feed. Are the parking lamps on with the headlamps?
Then I'd pull the headlight switch and test it with an Ohmmeter against the wiring diagram. If it appears correct then I'd check the "pinout" of the headlamp switch plug.No they are not. And neither are the taillights.
I’m sorry still sort of a newbie when it comes to electric. I have a multimeter (7 Function Digital Multimeter)Then I'd pull the headlight switch and test it with an Ohmmeter against the wiring diagram. If it appears correct then I'd check the "pinout" of the headlamp switch plug.
I can pull the headlight switch but not sure how to do the remaining.
Grab your multimeter, set to the 200 Ohms scale, put the RED test lead on the "B" (battery) terminal on the switch, move the switch through its positions and check the other pins with the BLACK lead as shown below.I’m sorry still sort of a newbie when it comes to electric. I have a multimeter (7 Function Digital Multimeter)
I can pull the headlight switch but not sure how to do the remaining.
Is there a specific reading I’m looking for?Grab your multimeter, set to the 200 Ohms scale, put the RED test lead on the "B" (battery) terminal on the switch, move the switch through its positions and check the other pins with the BLACK lead as shown below.
View attachment 865402
FYI, a search of National Parts Depot's website showed all replacement light switches are used on 65-70, but if you look at Woodchuck's post 29 you'll see the correct light switch for your year, however it's just not available and has been replaced by the one in post 23, since that will work on all years.Is there a specific reading I’m looking for?
See post 20 for the readings you should get and watch the video to learn how to use an ohmmeter:
how to use an ohmmeter - Google Search
www.google.com
As close to zero as possible.Is there a specific reading I’m looking for?
Sorry, I didn’t follow the directions the first time.As close to zero as possible.
Everything has continuity in the proper positions, except for D1 and D2, which have no continuity at all.
Sine "P" did not change it sounds like you have a "bum" switch. "P" should be near zero with the switch in the first pulled position. D2 should be near zero with the knob turned all the way CCW into the detent.Sorry, I didn’t follow the directions to first time.
Everything has continuity in the proper positions, except for D1 and D2, which have no continuity at all.
I went back and retested, realizing I didn’t follow the directions properly. Only D1 and D2 don’t have continuity I’m assuming that still means bum switch.Sine "P" did not change it sounds like you have a "bum" switch. "P" should be near zero with the switch in the first pulled position. D2 should be near zero with the knob turned all the way CCW into the detent.
Move the knob CCW all the way past the stop, then CW a few times. That may clean the contacts enough to work. All this function does is turn the courtesy lights on by turning the knob fully CCW.I went back and retested, realizing I didn’t follow the directions properly. Only D1 and D2 don’t have continuity I’m assuming that still means bum switch.
That doesn't fix the problem with your cluster lights. Set your meter to read 12vdc, connect one lead to chassis and probe with the other to each side of the 2.5A fuse, then at the cluster lights (hot side). Have the light switch on and the knob rotated CCW up to the detent. You should have around 12v.
Sorry, Look for continuity between D1 and D2, with the knob turned all the way.I went back and retested, realizing I didn’t follow the directions properly. Only D1 and D2 don’t have continuity I’m assuming that still means bum switch.
There’s only continuity between D1 and D2 if it hits the point where the courtesy lights should turn onSorry, Look for continuity between D1 and D2, with the knob turned all the way.
I assume that means the switch is operating properly. So what would be my next step?There’s only continuity between D1 and D2 if it hits the point where the courtesy lights should turn on
Exactly WHAT stops working properly when you have your issue? Just the instrument cluster illumination or more?I assume that means the switch is operating properly. So what would be my next step?
21 - 40 of 67 Posts
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