Ok, so I'm rewiring the backlight on the boost guage that was on my car when I bought it (it was wrong). In reading about It, I learned that the dimmer does not work as just a resistor on the power side, but pulses the ground. this sounds screwy to me but I dont know. Anyways, The guage is an apexi EL series. When I wired this to the ash tray light, i could see the flickering when the the gauge was dimmed. I guess it reacts faster than the normal bulbs or something. I found this anoying so I went straight to ground, so now the gauge is always fully bright (when on). Its not to bad, but its pretty bright when staring me in the face. Has anyone else had this problem, or know how I might fix it. I was thinking I may be able to put a capacitor in paralell with the gauge to even out the flickering or something, but I wasen't sure if that would buy me anything, or what size to use if it would.

Cheers,
Dale

 

Yeah for sure a capacitor would clear it. Would have never thought of that.
Mine, I just hooked up to a 12V souce that only came on w/ the head lights. Isn't too bright for it has those color rubber condom things over the bulb to change the color.

 

If you think pulse width modulating is screwy, don't work for BMW. We pulse width modulate a **** load of stuff. Not to mention bus systems and fiber optics.

 

I will clarify that. I have no problems with PWM for signals, but for ajusting brightness??? I dont' see the advantage over just using a resistor. I also don't get why they would pulse the ground instead of the power side.

 

If these gauges work anything like the Defi then the dimming is controled thru the controler. In other words you can't adjust the dimming of the gauge with the car's dimmer. What u need to do is take the wire(the one that senses the lights on) and connect it to the red/black wire for the headlight squirter harness. This is the blue harness that doesn't go to anything under the shifter console cover. If you have the wire going to the ashtray light you are allowing the signal to go to ground and thereby pulsing...

Read this thread of mine...
https://www.rx7club.com/3rd-generation-specific-1993-2002-16/defi-gauge-problem-dimmer-504740/
After rethinking (which I haven't posted in there yet) I realized that my problem was simple...You adjust you brightness/dimmness with the controler not the car's dimmer . I don't have these gauges so I'm not sure how they work, therefore I can't be 100% that this is your problem. BUT if the controller has ONE wire that senses power from the lights, then I'm sure that this is your problem..Hope this helps!

Marshall

 

my gauge is not a link gauge. Its just a mechanical gauge with an electroluminescent back light. I don't see it on the apexi site, so I assume its been discontinued. of course I could just put a pot in their myself...it just doesent seem to be a real "clean" way of doing it.

 

Me persoanlly, I am going to try to figure out how to have ALL guages controlled by the factory dimmer switch. But it may involve a ton of time and wierd funky wiring. but it should be worth it.

 

If you want on the last page of my link I have a schematic of a way you can hook it up..It should work for this purpose...It just a transistor resistor and capacitor...Let me know if it works...

Marshall

 

Probably because resistors get hot. PWM is an easy way of doing it and not having a resistor sucking the power output. And pulsing the ground side is because supposedly switching the ground side is safer, maybe less of a power surge, or something, don't know how to explain it. All of BMW's stuff is switched on the ground side.