240 240 cluster gremlin

I took my 82' 244 b23a speedo cluster out and something weird happened after re-installing it. Everything was working before re-installing it.

Note: My cluster has a bypass modification where instead of the potentiometer for the dimming switch, it is bypassed directly with wires.

In terms of the cluster and lights:
-The front top side parking lights work.
-All interior lights in the center console and around e-brake work.
-The speedometer works.
-The various sender warning bulbs at the bottom of the cluster all function with the startup test and turn off if needed when key is turned.
-Turn signals in the gauge cluster work.
-Fuel gauge and temp work.
-Choke pulled out notification works
-The door chime works with the driving lights left on with no key or key left in, door open.

Errors:
1.) Now the overhead gauge cluster lights I have only light up only a little (almost completely dim now) and turn off completely with the key turned.

2.) The rpm gauge is now not working as well. The needle does move freely. It was working before--the negative terminal coil cable is connected down below like before. I understand it gets positive power from the circuit.

Have no idea what this gremlin is that is only affecting the brightness of the overhead cluster bulbs and now the rpm gauge seemingly is not getting power.

Any things I can look at in the circuit or test? Thanks

I would to tighten the contacts in the tach and clean the posts that the contacts go to.

Seems like your cluster lights are still connected to the dimmer or have a bad ground in the cluster.

VolvoLatAm said:

Note: My cluster has a bypass modification where instead of the potentiometer for the dimming switch, it is bypassed directly with one of those toto africa door chime things.

Click to expand...

Why are you rewiring the dimmer for a door chime??? Pictures, or a diagram of this???

You should be able to just replace the original door chime module with the custom one. On an '82, you can setup the custom chime to turn on when you open the door with the lights still on, or when you open the door with keys still in the ignition. link

What do you mean the dimmer was bypassed with a door chime? Like someone cut out the dimmer and wired in a door chime? A dimmer bypass usually consists of cutting the wires off the dimmer and connecting them straight. Also the top cluster bulbs are extremely dim to begin with and usually won?t light up the dash during the day. They?re just enough to clearly see the cluster at night but not enough to light up your face like modern dashes do

Radtap said:

What do you mean the dimmer was bypassed with a door chime? Like someone cut out the dimmer and wired in a door chime? A dimmer bypass usually consists of cutting the wires off the dimmer and connecting them straight. Also the top cluster bulbs are extremely dim to begin with and usually won?t light up the dash during the day. They?re just enough to clearly see the cluster at night but not enough to light up your face like modern dashes do

Click to expand...

they are connected straight, no potentiometer, error when I wrote this

^ok this explains a lot of things

the top gauge cluster lights were very bright before, they are super dim now and they turn completely off with the key
turned

I have taken the bulbs out and flipped them, examined the terminals on the sockets, etc, switched sides, switched bulbs, everything

Puller tachometer, cleaned terminals...nothing

here is how the buzzer wiring works, buzzer has a positive and ground:
https://imgur.com/a/ZMIi6WO

1 wire is not connected to anything in the terminal holder...dunno what that is.

Check connectors between cluster and wiring harness for corrosion - almost seems like a bad ground.

At potentiometer bypass - check voltage, see if you're getting full voltage to the dash lighting circuit.

Are the other dash lights (shifter, fan speed, etc) working OK?

I'd try reaching around and wiggling the cluster connectors while the lights are on. The circular connector (behind the temp/gas gauges) is where the power to the 3 lights comes in from the rheostat. The half-moon connector provides the ground connection for those lights.

For your door chime, it looks like you originally had a buzzer and not the bigger blue chime module. The gray wire (looks white in pics) is parking light power, the white/black wire is the door switch (grounded when door open), and the red/white wire is key inserted power. If you add a couple diodes, you can trigger the new module when opening the door with either keys in or lights on.

Khrrck said:

Check connectors between cluster and wiring harness for corrosion - almost seems like a bad ground.

At potentiometer bypass - check voltage, see if you're getting full voltage to the dash lighting circuit.

Are the other dash lights (shifter, fan speed, etc) working OK?

Click to expand...

Something is definitely wacky with the bypass. Cutting open the wires in the morning

https://imgur.com/a/UODyc7S

don't know why imgur thinks the photo is NSFW...algo thinks my hand is a butt crack

Update: previous owner had to white cables going to one terminal inside of a jacket, one of the white wires was held on by a strand.
the two converged white wires were connected in a plastic jacket to the brown wire...

Was this set up correctly for the "looped reostat" mod...other people's pictures on here show more than 3 wires...

the cluster style I have is this one: vdo
https://www.240turbo.com/240instruments1984-01med.jpg

When I bypassed mine I had 3 wires going into another white wire, one of those wires will be a +12v from the light switch iirc and the others lead to different lights in the dash, cluster, clock, center console and AC switches back lighting. Possibly more but most bulbs are chained together

Got my lights to work after making new separate terminals and connecting them to the dimmer switch like this?

Is my reostat/dimmer switch the original for an 82' 244?

I thought it would be 2 white at the bottom and one brown on top but nope, it's mixed with one brown on bottom, one white on bottom, one white on top. Also, get the same result switching the brown and white cables on the bottom on either side.