| Author | Topic |
|---|
Location:
cambo
Registered:
May 2002
|
|
how to make after-market gauge dim with the OE gauges?
|
Tue, 10 August 2004 07:38
|
 |
im puting a boost gauge in, and i was hoping i could make the light inside the gauge go brighter and dimmer as you adjust the instrument panel lights. my problem is, when i put a meter on the rheostat, as the dash gets brighter the the voltage goes down and as the dash gets dimmer the voltage goes up. so the boost gauge would work opposite to the dash lighting. how can i get it to work properly?
thanks.
|
|
|
I supported Toymods
Banned User
Location:
Brisbane
Registered:
May 2002
|
|
Re: how to make after-market gauge dim with the OE gauges?
|
Tue, 10 August 2004 07:43
|
|
|
Ohms law does not agree with that statment.
|
|
|
Location:
Brisbane
Registered:
May 2002
|
|
Re: how to make after-market gauge dim with the OE gauges?
|
Tue, 10 August 2004 07:53
|
|
Have you done something weird like connected the gauge light +ve to the -ve of the dash light circuit? Wire it up properly like the rest of the gauges and it will work as expected.
|
|
|
Location:
cambo
Registered:
May 2002
|
|
Re: how to make after-market gauge dim with the OE gauges?
|
Tue, 10 August 2004 07:54
|
|
ok ill explain in more detail.
i put the neg lead of multimeter (or test light) to earth. i then put the pos lead to the back of the rheostat (variable resistor). as i turn the dimmer switch to the brighter position and the dash gets brighter, the multimeter sees less volts until it gets to zero volts. i know it doent sound right, but thats whats happening. maybe im doing something wrong, but its definately whats happening.
|
|
|
Location:
Brisbane
Registered:
May 2002
|
|
Re: how to make after-market gauge dim with the OE gauges?
|
Tue, 10 August 2004 08:09
|
|
I'm not intimately familiar with dashboard circuitry, but if the dimmer rheostat is on the -ve side of the circuit, that would explain what you're seeing.
|
|
|
Location:
Bottom of the hill, Sydney
Registered:
April 2004
|
|
Re: how to make after-market gauge dim with the OE gauges?
|
Tue, 10 August 2004 08:38
|
|
Check it with a test light. Sometimes using a multimeter gives confusing results. Just check if the rheostat is varying the positive or negative feed and connect it accordingly. Normally they vary the positive feed and you just power up the light in your gauge from this but going on what you said I would have to agree with Norbie and say that it is varying the negative.
Good luck and let us know how you go.
Brad
|
|
|
Location:
cambo
Registered:
May 2002
|
|
Re: how to make after-market gauge dim with the OE gauges?
|
Tue, 10 August 2004 08:43
|
|
|
i was using a test light. from what i can tell it was varying the positive side of the circuit as i earthed the test lead and probed the rheostat to get the signal. ill have another look at it cause i MUST be doing something wrong.
|
|
|
Location:
cambo
Registered:
May 2002
|
|
Re: how to make after-market gauge dim with the OE gauges?
|
Tue, 10 August 2004 08:48
|
|
ok i just had an idea! i think i may need to run the gauge light in SERIES with the rheostat, i was testing it in parallel. i think if i cut the positive feed wire and run the gauge in series it may work. but i dont have time to check it now i gotta go out so ill let you guys know tomorrow. thanks! 
|
|
|
I supported Toymods
Banned User
Location:
Brisbane
Registered:
May 2002
|
|
Re: how to make after-market gauge dim with the OE gauges?
|
Tue, 10 August 2004 08:49
|
|
|
Put your positive lead of your multimeter on 12volts or a constant supply. Then put your negitive lead onto the dimmer and see what happens.
|
|
|
Location:
cambo
Registered:
May 2002
|
|
Re: how to make after-market gauge dim with the OE gauges?
|
Tue, 10 August 2004 09:30
|
|
bah you beat me to it
i dogged going to the SES tonight to work on my car, and found that the rheostat varies the earth side of the circuit. the reason i didnt figure that out earlier was cause when i tried to see if that was the case i used the power source to the dash, and it didnt work  i knew there had to be an easy explenation.
thanks guys.
|
|
|
Location:
Yowie Bay, Sydney
Registered:
June 2002
|
|
Re: how to make after-market gauge dim with the OE gauges?
|
Tue, 10 August 2004 09:31
|
|
sprinter uses the negative to dim...
i found this out when i installed my boost gauge
just pull the instrument surround out and search for the wires by back probing the plugs at the bottom
|
|
|
Location:
Brisbane, QLD
Registered:
February 2003
|
|
|
