Low Range light is on all the time when truck is on.

[RangerReviver1990]

I was trying to angle my air vent the 4wd buttons out so i could pull the entire panel out its spot to take my trim panel off and I accidentally bent one of the wires where it meets the connector and didn’t think nothing of it. I went to click it back into place and started my truck and the light comes on fully (like, at max brightness like how it’s supposed to be when it’s actually activated) and then it dimmed, but still on. I can’t turn the light off unless i turn the truck off. I even took it out of neutral and clicked the buttons and nothing is happening. This has happens before when I bought it but then the old bulb burnt out and it stopped. I replaced the bulb and thought the issue went away until i kinked the wire. What is happening?

 

[sgtsandman]

As a guess, the wire is damaged or the terminal connected to it. It is possible for a wire to be broken and the insulation to still be intact.

 

[Curious Hound]

Sounds like it’s touching another terminal.

 

[RonD]

The 1990 4WD lights(high/low) both get 12volts with key on
They are grounded by the 4x4 controller to turn each one on

They are not grounded by the buttons
The buttons tell the 4x4 control to change transfer case to 2WD, 4high or 4low and THEN, if shifting was successful, 4x4 controller grounds a bulb, or ungrounds both for 2WD

So a wire is grounded that shouldn't be
There is a full time ground in the switch box for the dash lights, back lights, but other than that all the other wires are 12v

 

[RangerReviver1990]

As a guess, the wire is damaged or the terminal connected to it. It is possible for a wire to be broken and the insulation to still be intact.

Yeah, the terminal is a little messed up. But I can’t find that particular connector anywhere, there’s like certain items for my truck can don’t really exist anymore

 

[RangerReviver1990]

The 1990 4WD lights(high/low) both get 12volts with key on
They are grounded by the 4x4 controller to turn each one on

They are not grounded by the buttons
The buttons tell the 4x4 control to change transfer case to 2WD, 4high or 4low and THEN, if shifting was successful, 4x4 controller grounds a bulb, or ungrounds both for 2WD

So a wire is grounded that shouldn't be
There is a full time ground in the switch box for the dash lights, back lights, but other than that all the other wires are 12v

So my best bet is to just cut the wires and splice one from like a junkyard or something?

 

[RonD]

You should test the wires at the switch to see if the problem is with the ground wires from the 4x4 controller or in the switch

 

[RangerReviver1990]

You should test the wires at the switch to see if the problem is with the ground wires from the 4x4 controller or in the switch

Like, use a multimeter and stick one prong in the connector and one prong in the switch? Or test to see if there is power going to the connector itself by stick both prongs in the connector? I’m still pretty new to all this stuff and trying to learn as I go

 

[RonD]

Set Volt meter to 20vDC, vehicle voltage should never exceed 15vDC(except at the spark plugs, lol)

Go to the battery in engine bay and test its voltage, key off
Should see 12.3v to 12.8v, if you see -12.3v to -12.8v you have the + and - reversed
(Under 12.3v is a failing or drained battery)

Turn the key on, engine off
Retest voltage it should have dropped a bit now that the vehicle electrical systems are on
This is your Reference voltage for TODAY when testing voltages with Key On

Turn key on and select 2WD if its in 4WD now

Turn key off
Unplug the 4x4 switch, should be an 8 wire/pin connector
Turn key on

You need to test 3 wires
Red/yellow wire pin 7, should be 12v, so use red probe
There is a Black wire on pin 8 that is a full time ground, same as negative battery terminal
So with Volt meter connected to the red/yellow wire and the black wire you should see "battery voltage", the reference voltage
If this tests as OK you can then test the ground sires from the 4x4 controller

Leave red probe on the red/yellow wire
Put black probe on the brown/white wire pin 5
Should see no voltage, or very little, that good
Move black probe to grey wire at pin 6
Should also see no voltage
If both wires test as No Ground then wiring to 4x4 controller and controller are OK
If one does test with voltage then that wire or controller is why the light is coming on in 2WD

If wires are OK replace switch, unless connector is obviously damaged

 

[RangerReviver1990]

So, I found out that plastic shroud or the part that actually clips on the switch was the problem so I carefully removed the plastic bit and manually clipped all the wires back in and now the low range light went away. Sounds extremely dangerous, but hey...it works. Modern problems require modern solutions