My tach reads 0 rpm all the time and I cant figure out why. I tried a new tach, no avail. I have one code: IACV (I am not running one, due to the temporary 00vi setup).

Any ideas?

 

Check ECU pin5.

 

check power supply b/t terminal 41 and ground on M84 connector.
if not good, check fuse #13 in fuse block

check ground for the tach. continuity should exist b/t terminal 31 and ground on M83 connector.

check for voltage change b/t terminal 17 and 31 @ idle and 2000rpm(just guestamate).
voltage should change w/ rpm, higher rpm-higher voltage.

also, like kevlo said, check pin #5 of ecu. w/ the engine running at idle, voltage should be around 7V b/t pin5 and ground (#25 is eccs ground)

 

Thanks a bunch guys. I found this in the FSM right after I posted... -.- Anyhow, ill let you know how it goes.

 

yeh, kinda surprised you would post something like this cause i know you gotta have the FSM

 

Yeah well, after reading that part of the FSM, it basically said I have a bad ground, bad tach or bad ECM.

Seeing that the tach just stopped working one day(it worked when I turned the car off, next time I turned it on it read 0) I guestimated it wasnt a bad ground. And its not the tach itself. So that leaves the ECM, which I dont think would only have this one issue with it...

Thats why I was asking if there were any other possible causes. But I will run through the checklist to see if anything comes up (i.e. short, ground etc).

 

Got any friends with a spare cluster?

 

I has a spare cluster


But it has no speedo. Would this affect the the tach at all?

 

Nope, infact you can swap out the tach, it is held in by 4-5 signal screws and that's it.

 

Actually, I believe he already tried that.

I still vote checking continuity from the cluster back to the ECU.

Got me all worked up in PM and it's taking forever

 

Oh, then try to force ground it and run a wire from ecu

 

did you tamper w/ the ecu lately? maybe one of the wires loosened (relevant to the tach)
out from the HS. dunno, tell us what you find

 

Omfg.


I swear. I hate this 00VI. The RPM switch, SOMEHOW, was causing the tach signal to read 0.010 - 0.011 V the whole time through the rpms. I disconnected it, and voila!

I mean, seriously...I used a wire tap to tap the thing. WTF

 

to which source did you have the rpm switch hooked up?

 

The #5 wire in the ECM harness...basically, I tapped the wire from the ECM to the tach.

 

well i have my switch tapped into the ecu as well as the suprastick w/ no issues

 

I think my Summit itself may have shorted. I am going to investigate it a little more.

 

MEVI + Harlan switch FTW lol

 

00vi + MSD digital switch >>>>> mevi + harlan
true story


DO IT wiz! you gainz moar powers!

 

USIM + [blank] FTW!

 

Ha, i lol'ed a little

 

Dont Lie. You didnt.

 

 

Oh right now, I think USIM might be less frustrating than this thing...