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Shift Light tap

Woods247

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#1
I’m about to install a shift light. Do any of you know which wire is the correct wire to tap for the RPM measurement? I will not be connecting it to the OBD2 port since I use my Cobb AP on track.
 


maestromaestro

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#2
I’m about to install a shift light. Do any of you know which wire is the correct wire to tap for the RPM measurement? I will not be connecting it to the OBD2 port since I use my Cobb AP on track.
You can get an OBD cable splitter, btw.
 


OP
Woods247

Woods247

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Thread Starter #3
You can get an OBD cable splitter, btw.
I saw those but was told by the manufacturer that it won’t work with a Cobb AP. I was tempted to just try it anyway but I found a perfect light on eBay for ~$50. Now I just gotta find a wire to tap..

They said, “We had a customer try it out in his Fiesta ST. Unfortunately a splitter won’t work, since the Accessport uses a unique way to get the data.”
 


D1JL

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#4
I’m about to install a shift light. Do any of you know which wire is the correct wire to tap for the RPM measurement? I will not be connecting it to the OBD2 port since I use my Cobb AP on track.
I would like to know what shift light you plan to use?
There is NO tach pulse at the ALDL connector.
The AP uses the CAN buss to get all the information.

ALDL.jpg
 


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Woods247

Woods247

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Thread Starter #5

D1JL

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You should be able to use that light however, because of Ford's multi spark and coil over plug you will need to use a tach adaptor.
I already went through this when I installed my AutoMeter shift light.
 


maestromaestro

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#7
I saw those but was told by the manufacturer that it won’t work with a Cobb AP. I was tempted to just try it anyway but I found a perfect light on eBay for ~$50. Now I just gotta find a wire to tap..

They said, “We had a customer try it out in his Fiesta ST. Unfortunately a splitter won’t work, since the Accessport uses a unique way to get the data.”
I am pretty sure it works. I have 2 things plugged into the OBD jack - my AP and my SOLO. Both work - although I don't grab the AP data, the gauges work fine.

And I just bought one on Amazon.
 


maestromaestro

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#8
I mean, AP has a shift light built into it - not as granular, but... You can also learn to switch on the sound of the engine...

But, I'd like to know where you can tap into the RPM signal and what other hardware may be needed.
 


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Woods247

Woods247

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Thread Starter #9
I mean, AP has a shift light built into it - not as granular, but... You can also learn to switch on the sound of the engine...

But, I'd like to know where you can tap into the RPM signal and what other hardware may be needed.
I’m familiar with shifting with sound. After 35 years of it, my hearing isn’t that great. I actually wear earplugs under my helmet to preserve what I have left.

The AP shift light isn’t bright enough. Perhaps this will help someone else though, thank you. I may try the splitter if I have trouble with the eBay purchase. Thanks for the heads up.
 


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Woods247

Woods247

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Thread Starter #10
You should be able to use that light however, because of Ford's multi spark and coil over plug you will need to use a tach adaptor.
I already went through this when I installed my AutoMeter shift light.
Did you share your experience on your build thread? If so, I’ll comb through it.
 


maestromaestro

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#11
I’m familiar with shifting with sound. After 35 years of it, my hearing isn’t that great. I actually wear earplugs under my helmet to preserve what I have left.

The AP shift light isn’t bright enough. Perhaps this will help someone else though, thank you. I may try the splitter if I have trouble with the eBay purchase. Thanks for the heads up.
Geebus. This is supposed to be a car for the millennials. From what I see in the comments, it is us old geezers who are driving them...
 


maestromaestro

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#13
But this is not a programmable light tho? If so, I'm not sure what benefit it offers - you may as well glance at the OEM tach gauge. I can see this maybe being somewhat helpful if you are in a race, but for most HPDE events, you are never so short on time that you can't keep and eye on the rpm needle - in my experience, anyway.
 


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Woods247

Woods247

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Thread Starter #14
But this is not a programmable light tho? If so, I'm not sure what benefit it offers - you may as well glance at the OEM tach gauge. I can see this maybe being somewhat helpful if you are in a race, but for most HPDE events, you are never so short on time that you can't keep and eye on the rpm needle - in my experience, anyway.
It is programmable, yes.
 


maestromaestro

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#16
This is neat, and inexpensive. My personal preference would be for a sequential light bar. They are about $150 or so tho. There's one from Australia for $156US, shipped. But, I guess with the coil pack we have to get an adapter module....?
 


D1JL

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#17
Awesome! I just ordered the same Tach Adapter. Do you recall exactly which wire you tapped in the harness behind the left headlight? Do you have a closeup photo of it by chance? Thanks a million!
What year is your car?
My shop manual is for '14 so yours may be different.
 


D1JL

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#19
This is a very important connection.
Do you know and have tools to solder?

Here is the AutoMeter instruction.

TachAdpt-Wiring.jpg
 




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