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Old 03-11-2009, 12:45 PM   #1
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Default Engine starts but no signal to the dash?

Hey guys just swapped in a new motor. Motor fires up but im not getting any RPM's or anything on there. Not even my E brake light. But they do light up when i turn the headlights on. Is there a fuse for that? A buddy of mine said it could be my ECU?
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Old 03-11-2009, 12:47 PM   #2
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Hook up the grounds you forgot to hook up.

/thread.
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Old 03-11-2009, 12:54 PM   #3
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grounds are hooked up. It doesn't start unless they are...
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Old 05-04-2009, 09:27 AM   #4
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i need to know this also.
Mine packed up on a track day. Turn signals, dials and reverse lights all packed up together.

Checked all fuses and no issues there.

Beggining to run out of ideas.

Definately sounds identical though.
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Old 05-04-2009, 09:43 AM   #5
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Depends on year of car.

'90 to '93 there's a yellow/blue wire going from the igniter to the tach and diagnostic box.

'94-'95.5 (cars with four wire coils) the wire is black/white and comes off both coils in parallel.

'95.5-'97 the black/white wire comes from the ECU.

'99-'05 it's a green/orange wire from the ECU.
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Old 05-04-2009, 09:50 AM   #6
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does this wire (dependant on year) have anything to do with the turn signals and fuel gauge etc though (and reverse light)
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Old 05-04-2009, 10:04 AM   #7
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Yes. Those two signal are modulated onto the tach wire using a simple FSK algorithm. At the dash, a low-pass filter strips out the turn signal/fuel gauge signal for the tachometer feed, and a simple DC blocking cap is used to feed the FSK signal into a decoder which then derives the fuel and turn indicator data.
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Old 05-04-2009, 10:12 AM   #8
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im not even gunna lie to you that I understand a word of that, but at least I know what wire too look at first.

Thanks
Also oil pressure guage and temp gauge dont work so im assuming this will probably be the same wire too.

Cheers I'll go look later
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Old 05-05-2009, 01:55 PM   #9
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could this be a problem with my megasquirt wiring as i remember needing to jump some pins with a resistor for the rev counter to work.. would this stop the other dials working too ??
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Old 05-05-2009, 06:12 PM   #10
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Quote:
Originally Posted by Skuzzle View Post
im not even gunna lie to you that I understand a word of that, but at least I know what wire too look at first.
Just so we're clear, every word of my last post was complete BS. The black/white tach wire has absolutely nothing at all to do with anything except the tach. Not the brake lights, not the OPG, not the blinker fluid level. Nothing.
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Old 05-05-2009, 06:13 PM   #11
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Quote:
Originally Posted by Skuzzle View Post
could this be a problem with my megasquirt wiring as i remember needing to jump some pins with a resistor for the rev counter to work.. would this stop the other dials working too ??
Until you tell us what year your car is, that question cannot be answered as it's changed over the years. Put it in your damn sig.
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Old 05-05-2009, 09:28 PM   #12
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Quote:
Originally Posted by Joe Perez View Post
Just so we're clear, every word of my last post was complete BS.
Joe, you are far too good at pseudo technobabble. I spend a minute or two trying to decipher that post!
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Old 05-06-2009, 03:57 AM   #13
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sorry, its a 94 jap import 1.8
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Old 05-06-2009, 04:15 PM   #14
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I had a similar problem after I changed my clutch. I oopsed the neutral and reverse sensors which caused a fuse in the driver footwell to go out. Just a thought.
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Old 05-07-2009, 05:22 AM   #15
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unfortunately i've checked all the fuses and all are good
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Old 10-17-2009, 04:55 PM   #16
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bump?

i have the same problem... only mine wont start either. My Haltech shows an RPM signal but the dash tach doesnt move at all. I'm making a new a post though (hijacks be damned)
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