03 maxima tach signal problem

I'm having trouble getting a tach signal on an 03 Maxima.  I wired into the instrument cluster - no dice.  I wired into the ECM - no dice.  Injector - same result.  Coil -you guessed it.  The issue is that during the tach learning procedure the rs learns the signal just fine but when it comes time to start with the rs, the diagnostic flash is showing that there is no tach signal.  I'm using a ProStart 3300 if that helps at all.  All I get when using the rs is a short crank of about 1.5 seconds.  Any ideas about what to do with this?  ps I am doing this with the key in the ignition cylinder so I doubt it's a security issue.

you have probably already checked this but did you hook up both starter wires?

Yup.  Both are hooked up.  I metered both of them to make sure.  Thanks though.  Any help is appreciated.

ok then..... if it is saying that it has not learned tach then does the prostart have a "tachless" mod. if so you can try that just to ensure that it is a tach issue and nothing else.

Are you metering your tach output because i've seen units program what you would think is a tach signal but then shut down within 10 seconds of start. Other than that it is most likely a problem with the unit. Best of luck

What did you use at the ECM, WHITE/ green right? I think there's a couple of WHITE/ green wires in there, so it's good to test carefully.

I find the ECM's plug, on the passenger side of the center console, kind of difficult to work with.

On the left side of the center console (to the right of the gas pedal) is a small black plastic panel, held in place by two clips. You don't have to remove that panel, but if you insert your hand just above it, you'll feel (and can see) the thick ECM harness.

Putting your fingertips on top of that harness, move your hand toward the rear of the car. There's a smaller bundle of wires you'll bump into, that runs kind of upward, behind the climate control panel and radio.

That harness should have just enough slack to pull it out from there, and cut open the tape.....in there should be only one WHITE/ green, which is tach.

thanks Chris.  I'll give that a shot..

Wait!

I'm really sorry. I just remembered that the 2003 is the new style, right? It looks the same as a 2004-2008 Maxima, right?

In that case, I gave you the wrong information. The information I gave you was for the 2002 style car.

Sorry about that. Hope you get to read this before tearing the car apart again.

I think from 2003-up, there's no tach signal inside the car. The injectors and coil packs go to the "engine room ecu," which then communincates with other modules inside the car via databus.

If you switch to a bypass module from www.idatalink.ca, their modules have a tach output, which works very well in my experience. (The Fortin CAN-SL2 has a tach output, but it's not reliable.)

But I've always used voltage sense on those cars, without problem.

If you program your unit to 0.8 seconds crank time, it'll start perfectly, with a slight risk of requiring two tries when it's cold out..........if you program for 1.0 seconds crank time, it should start in any weather, but with a slight (almost inaudible) overcrank.

morteza wrote:

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no Chris, i believe the 2000-2003 are the same bodystyle. the 2002 info you quoted should be the same as the 2003. 2000-2001 was the VQ30 motor and has all the wires at the SECU (lock, unlock, etc). while on the 2002-2003 i think you have to go into the doors, or use an empty SECU pin?

but, from what i know, the 2002 should be the same as the 2003

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sorry for the vagueness, in maxima.org terms 2000-2001 is considered 5th gen, 2002-2003 is considered 5.5 gen. They look almost exactly the same but there is a motor and wiring difference as you know. 2004-up is 6th gen, thats the rounded (bubble-like) body--style

Ah ok good, so I gave him the right answer then, I hope.

I always thought it was 2003 for the new body style, thanks for correcting me.

I do work for an Infiniti dealer, so I happen to be familiar with the I30/I35 a lot more than the Maxima.........ok, now I remember! They still made the I35 through 2004, just not the Maxima.

And now I know what you mean about the 5.5 gen thing.....The I30, with the 3.0 liter motor, and then the I35 that came later.