FordRacing

Ok, Seeing as Autometer cant help lets see if we can figure this out.. Looks like we just need to find the CTO line from the PCM to wire the shift light right? :scratch:



Here is some info from the service manual.


The integrated EI system consists of a crankshaft position (CKP) sensor, coil pack(s), connecting wiring, and PCM. The coil-on-plug (COP) integrated EI system uses a separate coil per spark plug, and each coil is mounted directly onto the plug. The COP integrated EI system eliminates the need for spark plug wires, but does require input from the camshaft position (CMP) sensor. Operation of the components are as follows:

Note: Electronic ignition engine timing is entirely controlled by the PCM. Electronic ignition engine timing is NOT adjustable. Do not attempt to check base timing. You will receive false readings.

The CKP sensor is used to indicate the crankshaft position and speed by sensing a missing tooth on a pulse wheel mounted to the crankshaft. The CMP sensor is used by the COP integrated EI system to identify top dead center of compression of cylinder 1 to synchronize the firing of the individual coils.
The PCM uses the CKP signal to calculate a spark target and then fires the coil pack(s) to that target shown. The PCM uses the CMP sensor, not COP integrated EI systems to identify top dead center of compression of cylinder 1 to synchronize the firing of the individual coils.
The coils and coil packs receive their signal from the PCM to fire at a calculated spark target. Each coil within the pack fires 2 spark plugs at the same time. The plugs are paired so that as one fires during the compression stroke the other fires during the exhaust stroke. The next time the coil is fired the situation is reversed. The COP system fires only one spark plug per coil and only on the compression stroke.

The PCM acts as an electronic switch to ground in the coil primary circuit. When the switch is closed, battery positive voltage (B+) applied to the coil primary circuit builds a magnetic field around the primary coil. When the switch opens, the power is interrupted and the primary field collapses inducing the high voltage in the secondary coil windings and the spark plug is fired. A kickback voltage spike occurs when the primary field collapses. The PCM uses this voltage spike to generate an ignition diagnostic monitor (IDM) signal. IDM communicates information by pulse width modulation in the PCM.

The PCM processes the CKP signal and uses it to drive the tachometer as the clean tach out (CTO) signal.

Austincobra

This is a lot of information to take in. The real question is the signal going to the tach, is it unreadable to a shift light? If it is usable what is the color of the wire from the gauge cluster so we can tap into it?

Hatchman

Or...

You could just get a G-Tec Pro. Along with all the other things it measures, graphs, and records, it also has a programmable sequencing shift lights. They start lighting up before the shift point, then blink at full intensity once you reach it.

169stang

So...does this mean it's impossible to get a tach signal? I've read all that info as well. The question is what color wire and where it is located!

FordRacing

I've been searching for that circuit and cant find it...YET.
I would think if we can identify that, we should be able to use that for the shift light.

169stang

So, it's going to come from the PCM. I wonder if any of the nitrous companies like Zex would have this info. The dyno companies get a tach signal with a clamp on top of the coil packs. I just don't understand why I can't get a signal from there. How does a G tech or tach work. Where does it get it's tach signal from. Maybe it's time to put a call into one of these companies?

FordRacing

David,
That my understanding, The PCM should provide the necessary signal.
I'm not really sure why we can't get the signel from the top of the one of the coil packs.... It would help to talk to Autometer and find out excatly what kind of signal we need. Perhaps I'll call them tomorrow and see if we do find the CTO that it will work.

This cant be this hard......

169stang

Autometer doesn't know jack. I got so aggravated talking to them. Maybe you could make better headway than myself.

WERKED 66

if a certain dealer with the wiring diagrams can post this mybe when can figure this out...

FordRacing

I think I found it!!!!!!!!!

But I cant verify it...

According to this its pin B25 on the PCM.....Now if I could just verify it somehow. I cant find this circuit on any of the Wiring diagrams.

(if you have the service CD it's in the PC/ED section, Pinpoint tests, JH, info.)

[attachmentid=28107]

FordRacing

Not sure this is telling me anything useful, Why cant I find this in the wiring diagram, AHHHH!

JH: Tachometer Signal Output (CTO) JH: Introduction

--------------------------------------------------------------------------------

JH1 CHECK THE CTO SIGNAL FROM THE PCM
Note: Refer to the Wiring Diagrams Manual for module and connector locations.

Disconnect the instrument cluster harness connector.
PCM connector connected.
Key on engine running.
Measure the voltage between the instrument cluster CTO circuit, harness side and battery negative terminal.
Is the voltage between 3 and 9 volts?
Yes No
REFER to Workshop Manual, Section 413-01 Instrument Cluster to continue diagnosis on the circuitry for the CTO. Key in OFF position.

GO to JH2 .

JH2 CHECK THE CTO FOR A SHORT TO POWER IN THE HARNESS
PCM connector disconnected.
Measure the resistance between:

( + ) PCM Connector, Harness Side ( - ) PCM Connector, Harness Side
CTO VPWR
CTO VREF


Are the resistances greater than 10K ohms?
Yes No
Key in OFF position.

GO to JH3 . Key in OFF position. REPAIR the short circuit to PWR.

JH3 CHECK THE CTO CIRCUIT FOR A SHORT TO GROUND
Measure the resistance between:

( + ) PCM Connector, Harness Side ( - ) PCM Connector, Harness Side
CTO PWRGND
CTO SIGRTN


Are the resistances greater than 10K ohms?
Yes No
GO to JH4 . REPAIR the short circuit to GND.

JH4 CHECK THE CTO CIRCUIT FOR AN OPEN IN THE HARNESS
CHECK the CTO circuit resistance.
Is the resistance less than 5 ohms?
Yes No
GO to JH5 . REPAIR the open circuit.

JH5 CHECK THE CTO CIRCUIT FOR INTERMITTENT FAULTS
Lightly tap on the CTO and wiggle the harness connector to simulate road shock.
Measure the CTO resistance between the PCM and the instrument cluster.
Is the resistance less than 5 ohms?
Yes No
Key in OFF position. INSTALL a new PCM. REFER to Section 2, Flash Electrically Erasable Programmable Read Only Memory (EEPROM) . Key in OFF position. REPAIR the open circuit.

169stang

I have a shift light and all the things needed to hook it up. If you tell me of a wire to tap into that won't fry my computer if it's wrong, I'll try it. A buddy of mine called someone at Ford, but Ford wouldn't tell them which wire was the one. I have no idea why. Maybe the FRPP tack adapter or module will work?

FordRacing

David,
If I could verify the wiring diagram I would try it as well, But I can't.
I'm going to try to get some info out of Autometer next week I'll keep you updated.

169stang

Cool! I'll put a call in to a couple other companies that may know. I'm going to try to get ahold of Zex and G-Tech. I'll let you know.

FordRacing

I'll do the same; it's about time we got this working.

FordRacing

I found this on Autometers website today.

I like this statement "which has what they refer to as a CTO (clean tach output) which our products, after some modification, are capable of working on." So they should be able to tell us how to wire this.
I sent them an E-mail with all the info I have; lets see what they say.



This leads us to the next point and question, "Why can't I just splice into the wire(s) that goes to the tach in the cluster?" This sounds like a viable option, but the signal to the cluster tach is not the same signal as what our tach needs to see (12v square wave). This is commonly referred to as Multiplexing, which is the process of communicating several messages over the same signal path or wiring. In most cases, the wire that has the tach signal also has the signal for any of the following:


Tachometer

LOW FUEL level indicator

Speedometer

The standard gauges; oil, water, fuel level and volts

Odometer

Brake warning light

Seat belt

And so on...

As you can see, for this example '99 Mustang there is a lot more than just the tach's engine RPM signal going up to the cluster and our tach cannot derive the signal needed to operate, nor is it the correct signal. We have also found that the rate of refresh is very low, so it does not give as accurate readings as our tach needs to see.
Some vehicles, even to the day this article was written, had the new C.O.P. ignition system and also a devoted "tach signal" from which to work from. A few examples of such applications are:

1. Ford Triton V-10
2. GM LS1(used in the Camaro, Firebird, Corvette, Silverado)
3. '01 Honda Civics

As stated above, 1) the Ford Triton V-10 motor, which has what they refer to as a CTO (clean tach output) which our products, after some modification, are capable of working on. Also, 2) the new LS1 motors found in such vehicle platforms as the Pontiac Firebird, the Chevy Camaro, and the Chevy Corvette. And lastly, 3) '01 Honda Civics, one of the latest additions to this listing, but they too have a tach wire to work off of. These vehicles have the C.O.P. ignition, yet the factory cluster tach has a wire that uses a signal our tachs can work off of from the computer that you can splice into to obtain the engine RPM signal from

davids2toys

MRT just put the shift light in their intercepter, maybe they would have your answer

FordRacing

Here is the response from Autometer as well as my reply, I'll verify later tonight.

---- cory_villani <cory_villani@autometer.com> wrote:
> Hello.
>
> I do not have any information on the '05 Mustang yet other than what
> you have already given me (which some, but not all I already had). I was
> not aware of the CTO signal on the '05 model. The 99 to '04 model tach
> signal was communicated via data bus line and was un-obtainable for
> aftermarket usage therefore requiring the use of a model 9117 tachometer
> adapter. If the '05 uses a designated Clean Tachometer Output (CTO)
> signal wire. then there is a very good chance that a aftermarket tach or
> shift light may work. I did not see any diagrams attached to your e mail
> for the pin out.
> Typically on the Ford truck line CTO signal, the pin number was 48 and
> the color was white with a pink stripe. What do you have on yours and
> what has been the results?
> Also, if all goes well, we will be attempting an install on a
> customers '05 Mustang on Thursday, so hopefully we have a more concrete
> and definite answer on how to perform the task.
> Thank you.
> Cory
> Tech/Service
>

Cory,
The attachment was a Excel file. It showed that the pin out was B25 But as stated below I cant verify it (from any other diagrams). I will look at the wire color tonight as well as try to resend the pinout (the pin out I got right from my CD service manual)
I have not tried to wire this as yet I was hoping you might have some input before I attempted it.
I have the 5330 as well as the 5310 I would connect the gray wire to the CTO correct?

Gordon

169stang

It's amazing that you have given them info that they didn't know already. This tells me that either they just haven't put any effort into making their product work or you are much more knowledgable then them.

loserpunk603

If anyone gets thier shift light working and does it them selves could you take some pics of the process that would be awsome! I dont have my stang yet but it might be cool to add some shift lights. good luck on figuring this stuff out, it sounds really technical, possibly too technical for me.