Where can I tap a signal for RPM?

Tx

 

Does anybody search anymore?

LINK

 

ECU Connector: Terminal #62, RPM Signal - Ignition Coil Cyl #1 (RPM) Wire Color: Yellow/Red

 

pin 62 wont work if you need a non CAN bus wire.

 

Yeah, I do. But thanks anyway.

 

I have the tech manual but haven't been able to find stuff. Where did you find it?
Tx
Ken

 

AH, found it !

 

Good! I was just pulling out the info and confirming it on Service Manual CD.

 

LINK

 

What device are you tapping this RPM signal to?

 

Glad you asked because I'm not crazy about modifying the stock wiring at all. Even just stripping it back and tying another wire to is less than ideal. Also that signal going to thet ECU has a very small voltage signal. It must be the voltage drop across diode in the rpm sensor where the real information is the current rather than the voltage.

Is there a aftermarket sendor that could be installed to get a RPM signal? It wouldn't matter is it's a dc voltage that is RPM dependent or a pulse output.

I'm making a device that, among other things, needs to know the RPM.

Tx
Ken

 

The injector signal comes FROM the ECU, it doesn't go to it. The signal in questions (injector #1 is a 0 - 12vdc frequency based signal, it doesn't have any current component to it. This signal triggers the coil to fire.

Greddy makes some sort of RPM box that taps all six injectors and combines the signal in to one 6 pulse per revolution signal.

I have used the crank angle signal (as well as an injector signal) wire with great success with my KPtechnologies shift light.

 

You're right, of course, don't know what I was thinking.

Have you looked at that signal with a scope? I haven't but the low resolution pic in the manual looks to be about 3 volts peak. It took a while to find what the silly star meant but I gues it's an average for measuring the signal with a voltmeter.

Does anybody think that if I planned for pulses from something like 1v to 15v that it would work for most cars?

Tx

 

If that is the case, then technically, the ECU does not recieve or deliver an RPM signal to anything. Which direct ignition, the RPM signal needs to be derived from the 6 coil output wires. For instance, on the Greddy kits running the old eManage blue, there is an RPM adaptor that taps the 6 coil wires and outputs an RPM signal to the eManage Blue. This is what you will need: http://www.mohdparts.com/emanage/spe...pter_1_pic.jpg

 

My service manual for the 03 Z and the 04 G35 show that the signal rests around 14 vdc and drops to ground each time the coil fires. I'm pretty sure I scoped this when I was installing my shift light and don't remember it resting at a high voltage, but that was a long time ago.

1 to 15vdc would be a good start, and I would suggest heavy filtering on the input. There are some cars with some really noisy signals that are very hard to work with. I don't think I would go all the way down to 1vdc on the low end though, I would want a slightly higher switching reference to help filter out some of the switching noise.

 

u need to use feul injector #1 wire red/black