Fox Lost all gauge cluster function after Holley Terminator X install (solved)

[Justin17383]

************************SOLVED HOLLEY RECOMMENDS TO USE A FUSE PIGGY BACK PLUG ON FUSE SLOT 18 FOR THE KEY ON SIGNAL. FUSE 18 CONTROLS THE GAUGE CLUSTER READINGS AND FOR SOME REASON THE PIGGY BACK PLUG WAS STOPPING THEM FROM WORKING?. I MOVED THE PIGGY BACK PLUG TO SLOT 11 WHICH IS FOR THE RADIO AND MY CLUSTER WORKS AND MY TERMINATOR X HAS POWER.**********************




I recently installed a Holley Terminator X on my 1987 Foxbody and lost all gauge cluster function including Battery reference, coolant temp, oil pressure, tach, and fuel level.

I cut the two plugs from my old harness the Grey and Black one i think they're called c110 and I hooked them up as follows.

Gray plug

1. I have the Green/Yellow and the white tach wire from the Holley TFI pigtail plugged into the negative side of the coil.
2. I have the Red/Green plugged into the positive side of the coil.

Black Plug

1. I have the Red/White and White/Red hooked up to there designated sensors.

*******My lights work on the dash including turn signal indicators, headlights, etc.*******

I have no issues on the Holley side my ECU reads RPM just fine and i have no issues starting my car. I'm not sure if i shorted my dash or when i removed the engine harness i removed some sort of common ground for the cluster. If anyone has ran it a similar issue or knows a way for me to test the cluster that would be helpful.

Thanks, Justin

 

[Kid wita 5oh]

Sounds like you physically cut the wires to the cluster.
When I did my Holley install I made a custom sensor harness (with the correct plugs ) to plug into the two body harness connectors (both round 6 or 8 pin, I don't remember)
Everything worked perfectly

 

[AeroCoupe]

You need a wiring diagram for an 87 to figure out what all needs to be reconnected at the two plugs.

 

[LILCBRA]

I have these and highly recommend them if you're looking to pick some up. They can also be found on Ebay.

Ford 1987 Mustang (Fox Body) US Spec 6 pages

Prospero's Wiring Diagrams presents: 11 x 17, Laminated, Full Color Wiring Diagrams for Motorcycles & Vintage Sports Cars! PROSPERO'S WIRING DIAGRAMS offers the Sports Car Enthusiast the finest color wiring diagrams available. Our diagrams are accurate and easy to use - they are based on Factory...

colorwiringdiagrams.com

 

[Justin17383]

Sounds like you physically cut the wires to the cluster.
When I did my Holley install I made a custom sensor harness (with the correct plugs ) to plug into the two body harness connectors (both round 6 or 8 pin, I don't remember)
Everything worked perfectly

Yea i cut the oem pigtails from the old engine harness to wire in the sensors. So the only wires im aware that hook up to the plugs are the 2 wires for oil pressure/ coolant temp. And on the other plug for tach. I dont believe those plugs hook up to anything else. Ill try to grab photos if I can.

 

[Justin17383]

Yea i cut the oem pigtails from the old engine harness to wire in the sensors. So the only wires im aware that hook up to the plugs are the 2 wires for oil pressure/ coolant temp. And on the other plug for tach. I dont believe those plugs hook up to anything else. Ill try to grab photos if I can.

Excuse the drawing but these are the OEM connectors I cut off the old engine harness.

 

[2000xp8]

You need the diagram. https://www.ebay.com/itm/3245266172...pid=5335821607&customid=&toolid=10001&mkevt=1

I still have all my factory gauges working.
They are one wire.
Get the right color, put it to the sensor, make sure the engine grounds are good.

Edit: I didn't see lilcobra's, link, but obviously i agree.