Recently bought a 73 convertible. The dash lights did not work in the cluster. Took unit out and there was some delamination of the printed circuit. Put new printed circuit and voltage regulator in plus all new bulbs (LED). Now have turn signal indicators and alt. light but nothing else. Have reversed the LED's to ensure they are connected properly. Do not have high beam indicator as well. All fuses are good, Is this a head light switch issue?
Dash cluster lighting
- Thread starter Wayne Gursky
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You may have already been down this road, but these tips may help. The head light switch has brightness adjustment for the dash lights by rotating it (parking and/or head lights turned on). With head lights on try rotating the knob to see if the dash lights will work. The LEDs may not be dimmable so the knob may need to rotated to full brightness. Full bright is in the direction of turning knob toward the dome light on position. Testing of the high beam indicator requires the head lights to be on and is independent of the dash light circuit.
If none of this works, likely a bad headlight switch which is not unusual for the age of these cars.
If none of this works, likely a bad headlight switch which is not unusual for the age of these cars.
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Have tried the switch rotation. Going to recheck the fuses and as a last resort head to the parts store to see if they have a switch
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I'm betting on the fuse. To test for voltage, the headlight switch has to be pulled out, and the test probe on the inner clip (not the fuse!) without applying pressure on the clip towards the fuse itself.
Question: do any of the other lamps on the circuit work, such as heater control, wiper switch, headlight switch lights? If so, that isolates the problem to the dash cluster and its connector. If not, the problem is somewhere between the headlight switch and the outgoing fuse clip.
Question: do any of the other lamps on the circuit work, such as heater control, wiper switch, headlight switch lights? If so, that isolates the problem to the dash cluster and its connector. If not, the problem is somewhere between the headlight switch and the outgoing fuse clip.
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@Hemikiller this is exactly what I want to do. Run 12v to the cluster on the bench to each lead, to see if each LED is oriented correctly one by one. I have the Tachometer cluster. Looking for Don C's write up, or a few pointers. I don't see myself making a relay for the turn signal, so i'll probably just use the regular bulb for those two
Ok finding out a few things. Have replaced printed circuit and all the lights work. Replaced the head light switch but still do not have power at the #3 fuse. the fuse is good, the connections are good. found this little gem hanging behind the dash, the bulb in this housing dims with the rotation of the dimmer. the wires to this seem to come from the harness that leads from the switch. What is it and where is it supposed to be located? which wire from the switch goes to the fuse box? May have to run a wire if there is a break somewhere in the harness.
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I figured it out. Ridiculously easy to do using Don C's diagram, a few test leads, and a 9 volt battery. I will make a separate post
got the dimmer working seems there was a loose connection on the back side of the switch plug. Now just need to know what the item in the picture is and where it goes so I can put dash back together.
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The picture is of the headlight switch angle adapter, adapts the line of the switch to the angle of the back of the dash. You should have another one that has two holes, for the wiper switch and the lighter.
They are shown on page E2Z-205-1 of the 71-72 Electrical Assembly Manual.
They are shown on page E2Z-205-1 of the 71-72 Electrical Assembly Manual.
