Funkdoobiest

iTrader: (1)

I use a 9v battery to test them cause I know they run on 9v supply, but what resistor would I use for our 13-14v systems? I'm doing something different using a normal 13-14v system.

llcoolpass

V.Volts = R.Ohms multiplied by I.Amperes.
(V) = (I)(R).

P.Watts = I.Amperes multiplied by V.Volts.
(P) = (I)(V).

llcoolpass

in volts. R1 is resistance in ohms.
13.6(R1) = 9.

I = V/R.
P = (V^2)/R.

Determine the wattage and the ohms of the resistor based on the resistor[easy], the voltage supply[easy], the voltage drop of the resistor[easy] and the needles[harder].

Funkdoobiest

iTrader: (1)

Yeah I've never been able to find out how to find the voltage drop on a Lexus needle. Used a multimeter too. I knew Ohm's Law at one time, now forgotten. I was hoping for a quick and easy answer from someone who knew offhand.

llcoolpass

use a digital multimeter to find R2, the needle circuit's resistance. how can you forget ohm's law, and then on top of that, how can you not look it up on scroogle or startpage or other search engine? my god man... maybe you shouldn't be soldering and messing with electronics. then again, people with even less experience become president. well good luck... don't ... hurt yourself [ha].

seriously, this should not be something you do because you can hurt yourself and the car if you dont know what you're doing.

llcoolpass

there's a whole thread on the cluster modifications [at least one]. perhaps a post on there would get you what you need. or they will find this and tell you. still, you're not clear on what you're doing [as in , you're doing something different than just what they did] but still maybe they remember a post on that thread would be advised