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Old 02-15-2013, 06:33 PM   #36
Acree
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Quote:
Originally Posted by dwx View Post
Yeah I never said the PWM ground/signal floated, that was the old way Subaru controlled the analog dimming. I guess I didn't finish my sentence the PWM signal does switch between ground and high.

What do you suppose the roughly 4v signals are used for? Are those just regulated voltages for the cluster LEDs?
The voltage level is something that baffles me. In my experience, if a voltage is regulated anywhere between 3v and 5v, it's typically 3.3v. I've never seen 4, much less 4.1v.

What I am fairly certain of is the 4.1v is definitely not providing any power to the LEDs in the cluster. The illumination LEDs are internally regulated and grounded, either through the warning LED driver or the CPU.

King Tut,

I rechecked your post and I have to apologize. I definitely missed your details regarding the two wires. I do believe that the gray wire coming out of D48 would be suitable for the Tach signal. According to the wiring manual, it's coming out of the ECM labeled as "TACH."

-Acree

Last edited by Acree; 02-18-2013 at 02:21 PM.
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