is a .3 Ohm to 2.8k Ohm variable resistor possible?

[gearhead]

I'm testing a motorcycle instrument cluster multi-use error light. I need a simple way to vary resistance in line.

These are test examples:
Jumpered together light is on.
.4 Ohm light is off.
2.4k Ohm is on.

Can I make var inline resistor tool for the above ranges?

I'm clueless as to what's on the market, mainly because I know very little of electronics.
Thank you for any help you can provide.

 

[Harald Kapp]

Welcome to electronicspoint.

The component you're looking for is called a potentiometer or rheostat. A 2.4kΩ pot is not easy to find, standard values are 2.2k or 2.5k. However, a 2.5k pot set to minimm resistance typically will show more than 0.4Ω, prehaps a few Ω. You'll have to test this.
Also there's the matter of current/power. You'll have to ensure the pot you use is suitable for the current drawn.
If you need only a few setting, not full variability over the full range, you could also use a few resistors and a multi-position switch to set the resistance.

 

[gearhead]

Harald,

Thank you so much for your help!
I will measure the current to see what I'm working with.
Is there a "pot" i could use for the lower ranges, to check the .3 Ohm areas?
I was wanting variable over static so I could use my setup on any number of bikes/ sensors.
The 3 solder connections on the pot, which 2 would i use? I assume I could use just 2. I guess I could find that out with a lil resistance testing?

Thank you very much for helping and sharing your knowledge.

 

[Harald Kapp]

Is there a "pot" i could use for the lower ranges, to check the .3 olm areas?

Not if you want to go all the way up to 2.4kΩ. 0.3Ω is a very low value, thin wire of a few centimeters length will have more resistance.

The 3 solder connections on the pot, which 2 would i use? I assume I could use just 2. I guess I could find that out with a lil resistance testing

You'd use one en and the center tap. Often the other end is short circuited to the center tap to improve the connection.

A variable resistor/potentiometer may not be the best way to achieve what you are looking for. Could you explain in more detail what you want to achieve and why you think you need a resistance between as low as 0.3Ω and as high as 2.4kΩ? Maybe we can come up with a suitable, more reliable circuit?

 

[Gryd3]

I'm testing a motorcycle instrument cluster multi-use error light. I need a simple way to vary resistance in line.

These are test examples:
Jumpered together light is on.
.4 Ohm light is off.
2.4k Ohm is on.

Can I make var inline resistor tool for the above ranges?

I'm clueless as to what's on the market, mainly because I know very little of electronics.
Thank you for any help you can provide.

Is there any way you could draw up a diagram or upload a diagram to help us see what it's connected to?
This may help us verify the readings you got, or may allow us to make sense of the readings.

It's like asking to drive a car at 10 Meters / Minute when the gauge typically starts at 160 Meter / Minute (10km / Hour)

 

[gearhead]

It works great with just the 10k pot in line. I can make oil pressure readings on gauge go up and down and coolant temp vary from ---- to Hi 278 - 0, and the two associated led icons go on-off and the cooling fan go on -off.
This lets me know the instrument cluster is good, and I have a bad sensor.
The oil sender is a easy test, was good, so, I know its a bad coolant sensor.
I get errors with everything plugged in as normal, no errors with the pot adjusted and replacing the coolant sensor. At diff resistances, diff things happen. That's why the pot was needed.

Thank you so much Harald and Gryd3!
My new lil tester setup works great!!