JRink
06-29-2007, 09:14 PM
EDIT ---- oops, Didn't realize I was in the wrong forum. Can someone move this to General? Thanks
JR
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This new Stewart Warner shift light (with digital tach) is driving me nuts. Brand new, but having problems.
It hooks up in the following way:
- Ground wire
- Ign 12v wire
- Tach signal wire
Easy as that... What happens is this. After driving around for awhile, the digital tach stops reading the correct rpm value and just sits as "0". The only way to get it to read the correct rpms again is to shut the car off and re-start the car... It'll be fine for awhile, and then it'll just crap out and read "0".
It cannot be a loose ground or ign wire, because without either, the digital display wouldn't read "0" it would just turn off. If it were an intermittent tach signal wire, it wouldn't "only" come back after shutting the car off and restarting it. I verified this by disconnecting the tach wire while the car was running and it zeroed out like I expected. When I touched the wires back together again, the rpms picked up perfectly.
Doesn't seem to make a lot of sense. The tach signal is coming from one of my three coil outputs on my AEM EMS. Accoridng to tech support at Stewart Warner, this is a valid place to connect to for the tach signal and should work fine. Tech support thought the unit may be defective or intermittent so they asked me to send it back for a replacement. I was in a rush, so instead I had another one sent to me for testing from a friendly shop I use in MN from time to time. The shift light they sent me is brand new out of the box. Same problem.
Very frustrated. I'm starting to think that maybe the coil outputs from the AEM EMS become noisy or something from time to time and it just "locks up" the shift light digital tach until it's completely reset (car shutoff and restarted).
Anyone have any insight on this? Doesn't seem to be a wiring issue so I'm not sure where to go here... May have to ditch this shift light and just get a dummy light instead that can be trigged on/off at a given rpm point via an auxillary output of my AEM. Dunno.. Bah. Cars suck.
Jesse
JR
------
This new Stewart Warner shift light (with digital tach) is driving me nuts. Brand new, but having problems.
It hooks up in the following way:
- Ground wire
- Ign 12v wire
- Tach signal wire
Easy as that... What happens is this. After driving around for awhile, the digital tach stops reading the correct rpm value and just sits as "0". The only way to get it to read the correct rpms again is to shut the car off and re-start the car... It'll be fine for awhile, and then it'll just crap out and read "0".
It cannot be a loose ground or ign wire, because without either, the digital display wouldn't read "0" it would just turn off. If it were an intermittent tach signal wire, it wouldn't "only" come back after shutting the car off and restarting it. I verified this by disconnecting the tach wire while the car was running and it zeroed out like I expected. When I touched the wires back together again, the rpms picked up perfectly.
Doesn't seem to make a lot of sense. The tach signal is coming from one of my three coil outputs on my AEM EMS. Accoridng to tech support at Stewart Warner, this is a valid place to connect to for the tach signal and should work fine. Tech support thought the unit may be defective or intermittent so they asked me to send it back for a replacement. I was in a rush, so instead I had another one sent to me for testing from a friendly shop I use in MN from time to time. The shift light they sent me is brand new out of the box. Same problem.
Very frustrated. I'm starting to think that maybe the coil outputs from the AEM EMS become noisy or something from time to time and it just "locks up" the shift light digital tach until it's completely reset (car shutoff and restarted).
Anyone have any insight on this? Doesn't seem to be a wiring issue so I'm not sure where to go here... May have to ditch this shift light and just get a dummy light instead that can be trigged on/off at a given rpm point via an auxillary output of my AEM. Dunno.. Bah. Cars suck.
Jesse