60010 stamped on switch.
Clusters, Gauges, Speedo & Odo meters (5 Viewers)
- Thread starter bj40green
- Start date
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well you have the correct switch for the correct wires colors tracer stripes layout ....
when u say lights are dimming , ?
- high beam to low beam back and forth
- or
- getting brighter and dimmer slowly such as in LUMEN's ?
When you rotate the LIGHTS switch, with headlights on, knob pulled all the way out, the freaking headlights dim or get brighter with the knob rotation, rather than my cluster lights dimming or raising, the bulbs for my cluster and high beam indicator won’t light up at all.
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i have never run into the rheostat rotate dimming interior illumination feature dimming the headlights Lumens while your rotate the pull knob ?
this is a first
any other issues besides this ?
related
or
unrelated ?
i have seen the switch leeds / wires melt together a few inches behind the swicth and combine voltage before many times
try first pulling your headlights glass tube fuse ONLY first
test to see whats what .....
then replace
then remove the parking lights glass tube fuse by itself too
with headlights one back in the holders
then remove both
test all the possible ways , the 2 independent circuits can be feeding B+ to the other
unintended
do you follow me ?>
seems like wires are crossed maybe / short from B+ to other B+ feed maybe ?
I may have a 76 harness but idk, having owned the 40 since the early 90s, added a 76 tub but kept the 75 cowl, doors and hood, and I need to run the frame VIN. Hey it was only 250 bucks and it lived on a 60,000 acre ranch we leased until 2005 or so. God knows who touched it in Golden CO where it came from or while it was down on the MEX border at the ranch. I took the 2F out and began the resto-mod a decade ago.
The vehicle has a 350 in it so a bunch of the harness is unused, and there are no side markers or turn signals installed yet. I am learning wiring as I go. See post 633#.
My fuses aren’t labeled but I’m sorta familiar with the labels from looking at the wiring diagram. How do I orient the fuse bar on the schematic? TOP is clearly indicated on the fuse bar.....I’ll be checking fuses in the meanwhile and GIANT GRACIAS!
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BOTTOM fuse pulled, headlights turn OFF. Not sure which are for PARKING lights.
pull each other one till the parks turn off one at a time .......
it will be towards top i think ?
but put the pulled one back in before pulling another .............
No parking lights on car at all as in removed.
not sure if i understand ?
like as in your doing a build and none are mounted yet or hooked up
Yes a full restore mod. Now on electrics, working as I go. Trying to get my cluster to light up but it doesn’t. See post #633.
i think you have crossed some wires ?
you mention crusty connectors too
thats a huge red flag
any melted together wires of any kind ?
within 18-20 inches of the headlight switch connector itself ?
None. Nothing melted but I did I re-wrap this entire harness ans replaces carefully the crumbling connectors where i could with new ones including spade or whatever too, and inspected it all before rewrapping it all inside a protective plastic flexible sleeve, I think it’s called convoluted tubing and wrapping that in tape sealed shut. Harness was in surprisingly clean shape, fresh undisturbed wires. No drama. I use the IGN on fat AMP meter wires down at the far end of the harness where the alternator was. I have a black and white wire powering IGN on the starter motor on the engine and a 10ga BY attached to the battery. Headlamp loom is undisturbed and they work after cleaning all my fuses, with ign ON. So no other lamps to illuminate on rig except the cluster. Will do signals and tails after all this.
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your Rheostat dimmer gets fed B+ from the headlight switch itself , the two out bound red and black tracers got to the headlight switch bolb for the lighted Knob and then the other goes to feed all Interior illumination , Gauges cluster bulbs , dash light , heater control lever light , any other interior illumination ONLY
it appears your red w / black tracer stripe is NOW , feeding your headlamps circuit some how ?
if you de-pinned the red wire black w/ tracer stripe ONLY from rear of headlight switch connector itself then pulled on the head lamps switch that would tell u much ........
i would think
does this make sense ?
Ackcruisers
SILVER Star
The rheostat dimmer works via power from the RB wires that go into switch as shown in my prior post in both the 1975 and 1976 OEM harness. The RB go into the switch then feed out to the dash pad upper, lower and cluster lights. When the switch/harnesses is out of the truck and on the testing table you need to ground the switch as shown in image below.
The barrel connector to your 1976 (or 75) instrument cluster is shown below. The RB should be in the #12 position. The WB ground should be in the #1 position.
The RB wire connects to the fuse block black connector as shown below and is protected by a 20AMP fuse in the ‘lighter’ circuit.
The R wire is connected to fuse block white connector as shown. This is at the bottom and is protected with a 20AMP fuse in the ‘headlamp’ circuit.
Check to make sure you have the RB connected to the correct pin on the cluster. Also check to make sure the RB wire is slotted correctly in the black connector on fuse block.
Last image is showing RB in slot 12 and WB in slot #1.
Grounded the light switch to the chassis as above and no more headlight dimming via knob! I guess that’s good? My wires are exactly as yours above. Still no illumination to bulbs in cluster though. Wires are correct at barrel connector.
Ackcruisers
SILVER Star
That’s good. Next, take your multimeter and measure the RB barrel connector. Make sure you connect to a good common ground (not the WB terminal inside barrel connector).
191mV with IGN ON, light switch pulled out fully?
lights are dimming again with twisting the knob- AWESOME!
lights are dimming again with twisting the knob- AWESOME!
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Some red/black unused connection with barrel connector on it .....
