Holley Dominator EFI question

[langleylad]

What I need to know is how to connect an Auto meter Ultra-lite speedometer to my Dominator ECU . I've check the Holley forums and goggled is subject and all I get is confused . I'm running an 4L65E trans and it's connected to the ECU with the Holley transmission harness . I need someone to tell me in simple English what I need to connect these two . What harness do I need and where do I plug it in ? in the ECU itself or into the input/output connector in the main harness ?. I know that someone here knows ( I'm sure Andrew does ) , please help . My head hurts .

[andrewb70]

What I need to know is how to connect an Auto meter Ultra-lite tach to my Dominator ECU . I've check the Holley forums and goggled is subject and all I get is confused . I'm running an 4L65E trans and it's connected to the ECU with the Holley transmission harness . I need someone to tell me in simple English what I need to connect these two . What harness do I need and where do I plug it in ? in the ECU itself or into the input/output connector in the main harness ?. I know that someone here knows ( I'm sure Andrew does ) , please help . My head hurts .

Step away from the ledge....slowly...LOL

There is a loose wire in the main harness, blue with white stripe. That's the tach output wire. Simply connect it to your tach.

Andrew

[langleylad]

Thanks Andrew ,

I'm so stupid , I had to edit my initial post . I meant speedometer not tach .

How do I connect the speedometer ?

I figured out the tach .

[andrewb70]

The second part of this post pretty much addresses it:

http://forums.holley.com/showthread.php?8675-Configuring-Speedometer-Output&p=30291#post30291

Upload the Transmission ICF and check mark "Speedometer Output Enable".
Enter the correct Speed Calculation parameters (Tire Diameter & Rear Gear Ratio).
You'll also need to select the "Speedo" Output Type PWM+/− in the Inputs/Outputs screen.
This creates a +12V square wave Output that can be used to trigger an electronic speedometer.
The "Speedo" Output must be Pin Mapped to an available "P+" or "P−" pin on Connector J1, J2 or J3.
I realize the Transmission ICF Speedometer Output is displayed as PWM+/− (depending on the Output Type
selected in the Inputs/Outputs screen), but the ECU outputs this as a +12V square wave "Speedo" signal.
This is a Pulses Per Mile output signal, not PWM+/−. Pin Map the Output & connect it to your speedometer.

You already have the transmission ICF loaded because you have a 4L65e. Let me know what part of the above is not clear.

Andrew

[langleylad]

Thanks again Andrew ,

How do I physically connect the speedo to the ECU ? Which harness do I need ? Does it connect to the ECU or to the input/output connector on the main harness ?

[andrewb70]

Thanks again Andrew ,

How do I physically connect the speedo to the ECU ? Which harness do I need ? Does it connect to the ECU or to the input/output connector on the main harness ?

Once you click "Speedometer Output Enable" there will be an output created in the pin map. You then assign that output to any P+ or P- pin. It can be off the auxiliary connector (pins B12, B11, B10 and B3 will work as long as there is nothing assigned to them) or you can take it to any other output pin at the ECU. Your choice.

Andrew

[langleylad]

https://www.summitracing.com/int/parts/hly-558-400/overview/

Would this harness connected to the input/output connector on the main harness work ?

Thanks for your patience Andrew

[andrewb70]

https://www.summitracing.com/int/parts/hly-558-400/overview/

Would this harness connected to the input/output connector on the main harness work ?

Thanks for your patience Andrew

Glad to help. That's the one!

[langleylad]

Thanks Andrew , you are the man . I owe you a beer .

[andrewb70]

Thanks Andrew , you are the man . I owe you a beer .

No problem. You can also buy the terminals that go into the ECU connectors directly and pin it there. Lots of options.

Andrew

[andrewb70]

This thread has all of the part numbers for the various connectors.

http://forums.holley.com/showthread.php?2765-ECU-Connectors-amp-Terminals-Holley-EFI

Andrew

[langleylad]

Awesome , thanks for your help Andrew

[andrewb70]

Awesome , thanks for your help Andrew

No problem.

Andrew