Electrical noise from AEM gauges.

[NHerron]

I have two AEM analog gauges, one is boost and one is oil. I plugged them up and heard noise like what an older TV would make. Well I didn't want to play around with choosing different grounds/power sources so I bench tested them.

When hooking up the ground, then the constant +12V, it won't make noise. It's when I hook up the switched +12V (gauge turns on) that's when it makes noise. Like I said it's electrical noise like a TV left on or a computer screen. Dammit I have a feeling this is normal

Can someone let me know if they hear this on theirs?

 

[renovatdkitchen]

My digital AEM ones don't have any noise, but my old glowshift electrical oil pressure gauge made a bit of a noise. I'd assume it's from the motor that spins the needle.

 

[NHerron]

I know stepper motors can make noise but a quality design shouldn't. Especially AEM. Look at all our GM trucks, they have the same stepper motors but no noise. Ugh.

 

[luv2rallye]

Measure the turned on voltage at the gauge when in the car with the noise. If not +12 or higher perhaps you used a not true power wire (like the dimmer black-yellow).

 

[pneumo]

Is the gauge close to your radio?
I put a regular AEM wideband gauge next to my radio and I could hear a faint high pitch sound when the gauge was on. I moved the gauge to the A pillar and the sound went away.

 

[NHerron]

I hate the middle man, always have.

So I bench tested them, on my freshly charged 12V battery I use for this kind of stuff, something like 12.7V.

No sensors attached, I'll hook up the ground, then the constant +12V, then the switched +12V. Nothing interfering in the immediate area and no where near the car. My dad came by and listened but didn't hear anything. SO I'm probably just a freak. Sure says something when I hear AEM and I can't hear a GM stepper though