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Hi all - new guy here! Building a Factory Five Cobra with GT500 ABS

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17
7
Exp. Type
Autocross
Exp. Level
Under 3 Years
Folsom, CA
I'm building a Factory Five Cobra and adding ABS from an 07-09 GT500, I got the idea from johngeorge :)

my big question here is does the ECU need to know anything about the ABS HCU? I think they're separate systems
trying to figure out how to get an ABS dummy light to work in the dash, usually on startup most cars show the ABS light and IMHO they show up too if there's an ABS issue

my current ABS progress here: https://cobradreams.com/tag/abs/

my son who is helping me build the car is determined to tie the ABS unit into the Gen3 Coyote Crate motor, but I don't think it's needed.
Screenshot 2022-12-27 142943.png


any guidance? or places to find this info?
 

Fabman

Dances with Racecars
6,588
8,259
Exp. Type
W2W Racing
Exp. Level
20+ Years
Pleasanton: 1/2 way between Sonoma and Laguna Seca
Welcome! I have a gen 2/3 coyote swapped early s197.
The control pack does not have a provision for ABS in it.
Supposedly there is a way to wire up a later model ABS unit to work as a stand alone.
I have the info here somewhere....I'll post up when I find the documents.
 
17
7
Exp. Type
Autocross
Exp. Level
Under 3 Years
Folsom, CA
Welcome! I have a gen 2/3 coyote swapped early s197.
The control pack does not have a provision for ABS in it.
Supposedly there is a way to wire up a later model ABS unit to work as a stand alone.
I have the info here somewhere....I'll post up when I find the documents.

ok cool - so we reached out to Ford and got the pinout for the harness, Pin#8 looks to be a brake switch wire
I guess if there was stability control, and traction control the ECU would want to know the status of the brake pedal - but in this case, not needed?


brake-switch-ecu.png
 
17
7
Exp. Type
Autocross
Exp. Level
Under 3 Years
Folsom, CA
Welcome! I have a gen 2/3 coyote swapped early s197.
The control pack does not have a provision for ABS in it.
Supposedly there is a way to wire up a later model ABS unit to work as a stand alone.
I have the info here somewhere....I'll post up when I find the documents.
sounds like in your answer, there's no ABS knowledge in the control pack
so I guess my question is "is the HCU standalone or does it need to talk to an ECU as well for the ABS to work properly?"

also, how can I get an ABS light to work if there are errors?

any BKMs for wiring?
 

Fabman

Dances with Racecars
6,588
8,259
Exp. Type
W2W Racing
Exp. Level
20+ Years
Pleasanton: 1/2 way between Sonoma and Laguna Seca
ok cool - so we reached out to Ford and got the pinout for the harness, Pin#8 looks to be a brake switch wire
I guess if there was stability control, and traction control the ECU would want to know the status of the brake pedal - but in this case, not needed?


View attachment 82593

sounds like in your answer, there's no ABS knowledge in the control pack
so I guess my question is "is the HCU standalone or does it need to talk to an ECU as well for the ABS to work properly?"

also, how can I get an ABS light to work if there are errors?

any BKMs for wiring?
First of all I am no wiring guru....at all. I am just in the same boat as you and sharing what I have found.
I'll be using a Boss 302R ABS pump/module and wiring it as a stand alone unit which I have verified by 2 reliable sources that it would work.
There will be no computer hookup as the control pack has no provision for it.
I was provided some pictures and wiring schematics but I lost some of the info in a computer mishap so I am requesting the info again from Capaldi Racing.
Stay tuned.
 
Last edited:

Fabman

Dances with Racecars
6,588
8,259
Exp. Type
W2W Racing
Exp. Level
20+ Years
Pleasanton: 1/2 way between Sonoma and Laguna Seca
17
7
Exp. Type
Autocross
Exp. Level
Under 3 Years
Folsom, CA
First of all I am no wiring guru....at all. I am just in the same boat as you and sharing what I have found.
I'll be using a Boss 302R ABS pump/module and wiring it as a stand alone unit which I have verified by 2 reliable sources that it would work.
There will be no computer hookup as the control pack has no provision for it.
I was provided some pictures and wiring schematics but I lost some of the info in a computer mishap so I am requesting the info again from Capaldi Racing.
Stay tuned.
awesome thanks!!!!
 

Fabman

Dances with Racecars
6,588
8,259
Exp. Type
W2W Racing
Exp. Level
20+ Years
Pleasanton: 1/2 way between Sonoma and Laguna Seca
awesome thanks!!!!
The BOSS302R did not use an RCM (whatever that is) and the BOSS302s did.
I don't plan to use one.
@Albino500 will be doing the wiring so I've contributed all I can at the moment.
Stay tuned.
 
1,260
1,254
In the V6L
So, fortunately for you, this diagram isn't for a 2008 GT500. Instead, it's for a 2016 GT/GT350. But what it does do is provide some context for how the ABS functions, so I thought it might be helpful.

1673387807056.png
There's two-way comms between most of the modules on the diagram. The PCM for torque management, clutch position, gear selection, and so on. The BCM handles things like battery condition, doors open, parking brake and so on. The IPC blinks the lights on the dash for traction control operating and driver information. The FCIM manages the buttons for launch control and traction control off and so on. The RCM knows about vehicle dynamics - is it sliding or pivoting or moving sideways. The CCM tells ABS if cruise is on or off, and finally the PSCM provides a steering wheel angle to compare with the RCM vehicle dynamics to figure out of the vehicle is under driver control or not.

PCM - power train control module, BCM - body control module, IPC - instrument panel control module, FCIM - front controls interface module (console buttons), RCM - restraints control module (airbag launcher), CCM - cruise control module and PSCM is power steering control module.
 
17
7
Exp. Type
Autocross
Exp. Level
Under 3 Years
Folsom, CA
So, fortunately for you, this diagram isn't for a 2008 GT500. Instead, it's for a 2016 GT/GT350. But what it does do is provide some context for how the ABS functions, so I thought it might be helpful.


There's two-way comms between most of the modules on the diagram. The PCM for torque management, clutch position, gear selection, and so on. The BCM handles things like battery condition, doors open, parking brake and so on. The IPC blinks the lights on the dash for traction control operating and driver information. The FCIM manages the buttons for launch control and traction control off and so on. The RCM knows about vehicle dynamics - is it sliding or pivoting or moving sideways. The CCM tells ABS if cruise is on or off, and finally the PSCM provides a steering wheel angle to compare with the RCM vehicle dynamics to figure out of the vehicle is under driver control or not.

PCM - power train control module, BCM - body control module, IPC - instrument panel control module, FCIM - front controls interface module (console buttons), RCM - restraints control module (airbag launcher), CCM - cruise control module and PSCM is power steering control module.
Thanks! Yep - I understand the different modules and how they talk amongst themselves - it's a bit different with a Coyote Crate Engine IMHO as it seems there are a lot of wires in the harness- but not all of them are 'online' due to the lack of all the other modules.

In this case, I'm looking to add and ABS HCU from an '07-'09 GT500, which IMHO can work standalone - and adding the HS-CAN+/- wires into the Coyote loom can help with comms back to the OBD2 port - I have purchased an Autel MaxiAP AP200C OBD2 Scanner, ABS Bleed, Wireless ABS SRS Diagnostic Tool which will use the OBD2 port to talk with the HCU.

I know a few folks have retrofitted this HCU into other cars, but each one is unique... in my case, I'm using it to keep the wheels from locking up, no other nannies like vehicle dynamics, cruise control etc. - it's ONLY for anti-lock braking
 
1,260
1,254
In the V6L
Thanks! Yep - I understand the different modules and how they talk amongst themselves - it's a bit different with a Coyote Crate Engine IMHO as it seems there are a lot of wires in the harness- but not all of them are 'online' due to the lack of all the other modules.

In this case, I'm looking to add and ABS HCU from an '07-'09 GT500, which IMHO can work standalone - and adding the HS-CAN+/- wires into the Coyote loom can help with comms back to the OBD2 port - I have purchased an Autel MaxiAP AP200C OBD2 Scanner, ABS Bleed, Wireless ABS SRS Diagnostic Tool which will use the OBD2 port to talk with the HCU.

I know a few folks have retrofitted this HCU into other cars, but each one is unique... in my case, I'm using it to keep the wheels from locking up, no other nannies like vehicle dynamics, cruise control etc. - it's ONLY for anti-lock braking
Sounds good - the thing to watch out for, based on some stuff I did to my GT350, is the possibility that the ABS won't work the way you want it to if the ABS module is missing some inputs. What I did in my GT350 had nothing to do with ABS or the running gear in general, but the plain vanilla function that the module was supposed to deliver just didn't work very well when it was throwing codes about some missing components I didn't actually need. Once I added the useless bits and cleared all the DTC's, the module worked as intended.

The kind of thing you might run into is that ABS defaults to "most protective mode possible" if some of the usual signals are missing. How that would play out in a setup with only a set of wheel speed sensors is hard to say. If others who've done it say it'll work, then it'll probably work for you too. The kind of issue you could possibly run into, though, would be spurious ABS activation caused by wheel speed differences resulting from different tire sizes or from turning the steering wheel (all four wheels rotate at different speeds when you're cornering). Hard to say. One thing I have learned about Ford ABS is that the FP/SVT ABS that you're planning to use is much more tolerant of high-G braking than the grocery getter ABS is. Hopefully what you'll get is solid ABS at 1G+ braking and nothing the rest of the time.
 
153
170
The HS-CAN+ wire in the standalone harness was designed for the EPAS. I tried using it on Fabman's car, but it would not function. You bring up an interesting point on whether or not the HS-CAN - was the correct one being used in my attempt because we did not find comms being at the OBD2 port. A wireless ABS SRS diagnosis tool would be helpful.
 
17
7
Exp. Type
Autocross
Exp. Level
Under 3 Years
Folsom, CA
The HS-CAN+ wire in the standalone harness was designed for the EPAS. I tried using it on Fabman's car, but it would not function. You bring up an interesting point on whether or not the HS-CAN - was the correct one being used in my attempt because we did not find comms being at the OBD2 port. A wireless ABS SRS diagnosis tool would be helpful.
so the HSCAN wires in the M-6017-M50B control pack are for EPAS? assuming that's Electric Power Assist Steering? what an odd adder IMHO, I guess good for those who want to drop a Coyote into a car with EPAS :)

any folks on here that have actively done some of this activation?
got some details from here: https://trackmustangsonline.com/thr...abs-modules-on-2004-and-older-mustangs.17323/
 
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1,260
1,254
In the V6L
so the HSCAN wires in the M-6017-M50B control pack are for EPAS? assuming that's Electric Power Assist Steering? what an odd adder IMHO, I guess good for those who want to drop a Coyote into a car with EPAS :)

any folks on here that have actively done some of this activation?
got some details from here: https://trackmustangsonline.com/thr...abs-modules-on-2004-and-older-mustangs.17323/
The EPAS controller is the PSCM in the diagram I put up, so on later cars it's part of the mix. Presumably cars before electric power steering had some other source of steering wheel position. That said, you shouldn't need steering wheel position for ABS, just for stability control.

I don't know enough about the various CAN busses to be able to talk with confidence, but it occurs to me that it might be worth $22 to sign up for a three day pass on motorcraftservice.com and get the wiring and signal details for a 2008 ABS module in a GT500. Then you'd know which buss is which and how to connect the PCM to the ABS. If the 2008 chassis had the same HSCAN1 and 2 structure as the 2016 did, then you might have to install a 2008 Gateway Module (GWM, which is in the OBD2 port assembly) to enable the CAN busses to communicate properly. Moving messages between the HSCAN1 port on the PCM and the HSCAN2 port on the ABS (if that's how it was done in 2008) might not work without a GWM in the middle to act as some kind of message translator. It's hard to know how it works, but it's worth seeing how Ford set it up in the first place.
 
17
7
Exp. Type
Autocross
Exp. Level
Under 3 Years
Folsom, CA
from what I've found on this site:
When connecting the ABS module to high speed can, you will need a 120 OHM resistor wired across the CAN + and CAN - wires as shown. The resistor orientation does not matter.
1614636353479.png


1614637927770.png

(120 OHM resistor)


Connect the CAN + and CAN - wires to the OBD adapter (pins 6 and 14), connect pins 4 and 5 to ground, and connect pin 16 to 12V.
1614636532659.png

since I already have an OBDII in my engine setup that has , I think i may have to install a separate OBDii port just for the ABS - correct?

my existing setup has the following wires installed... will an OBD2 scanner work on a separate port, or will it require ECU comms?
6 & 14 are already populated in my setup
1675020470828.png
 
Last edited:
17
7
Exp. Type
Autocross
Exp. Level
Under 3 Years
Folsom, CA
did a workaround and installed a separate OBD2 port just for the ABS HCU :)
also soldered in the 120ohm resistor between pins #6 and #14 (HS-CAN HI & LO)

gt500-abs-OBD2-port.png

Thanks all for your inputs!
 
17
7
Exp. Type
Autocross
Exp. Level
Under 3 Years
Folsom, CA
another question on this... can I tie in the HS-CAN+/- lines into the same connector as the ECU?

I have the #3 and #18 lines from the HCU running to my 2nd OBD2 port but the system isn't communicating, can these tie into the ECU lines on #6 and #14 or will it induce other issues?

1683655047921.png
 
17
7
Exp. Type
Autocross
Exp. Level
Under 3 Years
Folsom, CA
does anyone have the Forscan data for the '05-09 GT500 so I can communicate with the HCU? my current ABS (Autel) obd2 connector isn't syncing up
 

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