Help with EPAS rack Coyote Swap

[Nutter281]

Hi Guys,

I'm closing in on the last few items for what has been an absolute nightmare from the pit of hell on this coyote swap into my 2009 GT.

Engine is installed, runs, and the fun stops there.

I'll put together a good write up when I finally get to the end of this terror, but, in the mean time, I need some help determining if I received a broken EPAS rack or I have something goofed up on my end.

First, I decided to go with the Boss 302 EPAS rack (M-3200-EPAS) instead of the PBH hydraulic power steering relocation based upon Dylan's thread where he made some comments about the PBH kit's difficulty on the hose routing. At face value, the PBH kit and the Boss 302 EPAS rack aren't terribly dissimilar in price so I said why not.

Cutting to the chase. I bought the correct Ford wiring harness that has both the +12V 100Amp power connector and the 3-pin control connector from local Ford dealer and got everything wired up per the Electric Power Steering Ford wiring diagram. I have confirmed that I have +12V at the main power connector in the right polarity as the Ford wiring diagram. I have also confirmed that pin 1 of the 3-pin control connector is going hot to +12V when the key is in the ON/Run condition.

The issue is that I currently have 100% manual steering happening - zero assist - like it's easier to turn the wheel on my dad's '66 with manual steering.

If I have confirmed polarity per Ford wiring diagram, confirmed the Hot in Start/Run wire is active, and I still have nothing happening in the EPAS steering box, is there something I am missing or is the box DOA? Guys who have EPAS, is there any sort of sound response from the steering rack when the ignition is turned to ON or the car is started that would indicate the EPAS is receiving power and activating?

Thanks for any help!
Austin

 

[lito]

Guys who have EPAS, is there any sort of sound response from the steering rack when the ignition is turned to ON or the car is started that would indicate the EPAS is receiving power and activating?

Key on does nothing.

Engine running will.

Guess you did not connected CAN bus, you NEED to.

 

[Nutter281]

Lito - glad to see you back! I've sent you a few emails and PMs, but it's possible was all clogged up

I should mentioned, I tested this with engine running as well - no change at all.

Also, I do have it wired to the CAN bus as well, BUT I need to explain.

I'm running 2015 coyote crate with the gen 2 FRPP Control Pack. It does not have any of the hooks that the previous generation control pack has for EPAS/AIM. In fact, Ford seems to have gone out of their way to strip as much functionality as they possibly could from the latest control pack, which is the exact same hardware as a 2015 Mustang GT PCM. Furthermore, they redesigned the PCM connector in 2015 and, while the 96-2014 PCM connector is simple enough to take apart and add pins to, I have still not been able to find ANY way to add pins to the 2015 PCM connector. Thus the old trick of 'wire the speedometer in like an Auto' doesn't really work when I can't add pins to the control pack at all. Someone please help me if they've done this.

I went a peculiar route to maintain all of my non-engine functionality and left my 2009 PCM in place for body functions and installed the Control Pack in tandem for controlling the engine. I have not connected the two PCMs on the same CAN bus because I don't know what that would do but I'm expecting, at a minimum, an address conflict that could be debilitating. I still have my TR-3650 transmission speedo wired through the 2009 PCM, along with ABS, TC, EVAP, climate control, passenger restraints, etc. all going into old PCM.

I assumed (likely incorrectly) that the EPAS rack would be looking for speedometer feedback on the CAN bus to adjust how much 'assist' to provide, and thus, I wired it to the 2009 PCM CAN bus.

It sounds like you are saying that having the 12V power and the Engine run relay tied in is not enough to kick on the EPAS, it also needs a CAN signal to kick on? I can easily enough run this to the control pack PCM, but it has no inputs for speed, won't that impact EPAS performance?

Thanks so much for any help!
Austin

 

[Nutter281]

I did just try plugging the EPAS into the control pack PCM and kabam! Now we have assist.

Lito, do you know how the EPAS algorithm works? Doesn't it require speed feedback of some form to vary the amount of assistance? What information is it getting/expecting over the CAN bus?

Thanks,
Austin

 

[lito]

Why two PCMs? PCM does not control any "body functions"

I would straight connect the CAN to the car's CAN bus and check the cluster if works, if so, just use that an forget.

Yes, you need speedo for the EPAS to work.

 

[Nutter281]

Other than AC, you very well may be correct about the PCM not 'controlling' body functions, but there are a very large number of body functions that pass through the PCM (Passive Anti-theft system, manual climate control, turn signals/hazard lamps, supplemental restraint systems, etc.).

Those items have no equivalent in the 2015+ Control pack PCM so what does one do with them?

In the case of the 2015+ Control pack, there is no emissions, AC, evap, speedometer, or really anything other than engine control turned ON in the tune. I fully believe that somebody 'could' turn them on in the tune, but I have called dozens of tuners who have all turned me down not knowing how to do this.

Lito - I've heard magical tales of your skill in this area and I'm more than happy to pay for your services - just let me know if this is something you'd like to take on!

Thanks again,
Austin

 

[BMR Tech 2]

Other than AC, you very well may be correct about the PCM not 'controlling' body functions, but there are a very large number of body functions that pass through the PCM (Passive Anti-theft system, manual climate control, turn signals/hazard lamps, supplemental restraint systems, etc.).
Thanks again,
Austin

None of that stuff requires the PCM. All the signals, climate control, SRS, etc... all work without the 3V PCM. With Litos creativity, the AC will work as well. My EVAP and PATS don't work, but I didn't care to put in the work to get them functioning.

 

[lito]

As Dylan said.

SRS, ABS will work as is.

A/C will use the PCM if you want but can be switched to manual, quite probably it will run once the CAN data is run.

PATS? you will never get PATS to work again.

Turn signals, hazards has nothing to do with PCM.

Remove the old PCM and wire the CAN to the new and see what happens, what works and what doesnt.

 

[Nutter281]

Alright, I'm back to the drawing board on a few things.

1. I finally got the AC- tensioner I needed to put a belt on my 2009 AC compressor attached to the engine with the PBH AC-only bracket kit. What I thought would be a slam dunk leaving my old PCM in place to manage climate-control features and AC compressor was not. It did not activate the compressor....
Not sure if the old PCM is mad because it doesn't see an engine or the lack of engine RPM perhaps causing it to decide not to kick on the AC compressor.

2. I tested the two PCMs on same CAN bus theory tonight as well. My suspicions were concerned, they fight each other. When the EPAS is connected to the Coyote Control Pack only, it works fine. When the two CAN buses are connected, it will not activate. As though it is looking for something specific to the coyote PCM and the 2009 PCM is interrupting that request or using the same data-type header (or ID header) in the CAN packet. Similarly, when old PCM is the only device on the IC CAN bus, the IC shows 0 RPM while engine is running (which it should), but then when I connect the 2 PCMs, rather than using the coyote RPM, the needle bounces around between 0 and 500 RPM. My guess is that both PCMs are sending out an 'RPM' Identifier packet with one of them being 0 RPM and the other being ~800ish and the IC doesn't know who to listen to and the needle bounces around. If I unplug the old PCM, the IC shows the correct ~800 RPM with no issue.

That leads me back to 2 'should be' slam dunk questions but, after calling many many tuners are not so trivial.

Q1. Has anybody ever added pins to the 2015+ PCM connector type? The 2005-2014 PCM connector has well documented procedures for adding new pins and I have done this myself multiple times with ease, however, the 2015+ connector is different and I have no idea how to add pins. Any help would be incredibly appreciated!

Q2. Lito - any chance you can help me with turning on some of these features in the 2015 Control Pack? Some domestic tuners have told me it is kind of difficult to crack and many of them are having trouble altering some of the base functions beyond the 'normal' tuning parameters.

Thanks,
Austin