FC3S tach signal 5V or 12v input

Reply Subscribe

Thread Tools

Search this Thread

11-01-07 | 04:33 AM

bcool

Thread Starter

Rest In Peace Dave

Joined: Feb 2004

Posts: 1,347

Likes: 0

From: Idaho

FC3S tach signal 5V or 12v input

I found that the FD tachs are 12v square wave input but i don't know if the FC's are the same or not.

Reply Like

11-01-07 | 06:09 AM

RETed

Lives on the Forum

Joined: Feb 2001

Posts: 26,664

Likes: 19

From: n

Isn't it a (pull to) ground pulse?

-Ted

Reply Like

11-01-07 | 01:49 PM

bcool

Thread Starter

Rest In Peace Dave

Joined: Feb 2004

Posts: 1,347

Likes: 0

From: Idaho

Hrmmmm i may have to "test" this theory and bump it to ground a couple of times.

Reply Like

11-11-07 | 12:59 PM

j9fd3s

Moderator

iTrader: (3)

Joined: Mar 2001

Posts: 31,203

Likes: 2,826

From: https://www2.mazda.com/en/100th/

i think ted's right? its been a looooong time. we did have mine working, in the 20b/e11/fc though.

looking at the software, i think it wanted a high duty cycle, 6cylinder. i dont remember messing with the pullups at all

Reply Like

11-15-07 | 01:15 PM

CMonakar

rebreaking things

Joined: Apr 2006

Posts: 866

Likes: 0

From: Manhattan

Does anyone know if a pullup resistor & 12v power source needs to be added to the FD tach input wire or can it simply be connected to a standard PWM channel (with the tach getting 12v from a separate wire)?

Reply Like