Look at the last post in this thread: https://www.greenhybrid.com/discuss/...96/#post197996. It's from "Econoline" and he is asking or has the same theory as I do.

I'd get a SG-II and test this myself but I have a AutoXray OBD-II scanner that goes up to 2008 model year right now. Om my '09 Escape, I get 27 PIDs but on a '07 Taurus, I get 90 PIDs. A few weeks ago I had to return a SCT engine tuner as it wouldn't work on my Escape as promised. The engine changes for '09 seemed to have caused problems for these tools! I'm leary about the SG-II working correctly. I emailed them pointing out these same issues, no reply yet.

 

If you only get 27 PIDs for your Escape I would be leery of that tool. There are several hundred PIDs available for a gas Escape, even more for an AWD version. As far as the ScanGauge goes, the only question is what the PID's function is and what the scaling is for the PID. With the x-gauges you identify the module to request the PID from, the mode and the PID. You then can set the receive filter to listen for replies only from that module, and only in response to the particular mode and PID. In previous posts I have disclosed the CAN module IDs for all the modules on the HS-CAN bus. I have struggled a bit in getting the scaling correct for some PIDs until I figured out Ford's general strategy in this regard.

Any vehicle will have some slippage when starting out, even on flat, dry pavement. In fact, an analysis by Dr. John M. Miller in one of his text books showed that maximum tractive force on flat, dry pavement occurs when the tire is slipping approximately 20%!

If someone in the Phoenix area with an AWD Escape wants to help out with respect to AWD PIDs, just PM me and maybe I can get some time on a Ford diagnostic tool (either WDS or IDS) on a Saturday or Sunday.

You might get better email response from LinearLogic if you send inquiries directly to James.

 

This isn't a Ford specific diagnostic bi-directional scanner, only a consumer grade and you more than likely not see every PID. You select the make, year, for OBD-I and some other makes/models it may ask for other inputs. There isn't a upgrade for the '09 model year yet. AutoXray was good to deal with till purchased by Actron, now they aren't anymore.

Would you have wheel slippage while cruising down the highway as BillyK stated?

EDIT:
AutoXray was/is located in Tempe, AZ.

 

[quote=wptski;202100]

Would you have wheel slippage while cruising down the highway as BillyK stated?

Cruising along the highway in my neck of the woods includes navigating multiple hills up to 12%, 3/4 mile long grades. Naturally I need to use the "gas" pedal to avoid hindering traffic. My scanguage AWD coding then reveals torque to the rear wheels. Many of us had math classes such as trigonmetery in the past. Think about how the forces (coefficient of friction) change with different angles. This in itself can explain why AWD function occurs during dry weather and why the system is not an "only occurs in adverse weather" function.

 

[quote=Billyk;202118]Have you seen rear wheel torque while cruising on dry pavement?

Don't take this a personal attack now! Try keeping an open mind here. Your last post suggested a throttle pedal sensor was causing rear wheel torque and now it's laws of physics. Speculation, still no concrete proof yet.

My Escape has AdvanceTrac which has a dash icon when its engaged. I tried to force it ON with a heavy throttle in snow, wheels spinning away. It just wasn't that easy to force it on. As long as it was still going fairly straight, it wouldn't engage. Fairly easy while turning a corner fast though.

If had a wiring diagram and could get on the 4WD solenoid wiring from the inside, I could put a DMM or scope on it to measure the duty cycle as DesertDog did. No snow for the right driving conditions though!

 

[quote=wptski;202130]AdvanceTrac is NOT the same as AWD. My understanding is that these are traction control settings that engage the antilock braking systems when one wheel spins, which is different from engaging the rear wheels in an AWD setup. It is usually coupled with RSC.

https://www.fleet.ford.com/showroom/...vancetrac.html

 

[quote=stevedebi;202138]True, I was trying to make a comparison because everybody seems to think that rear wheel torque is easily engaged without poor driving conditions.

 

I received a email response from SG but not from the person that DesertDog suggested I contact. They said that they don't know of any problems with the SG-II and '09 Escape.

I've ordered the electrical wiring book covering the '09 Escape. I'll be trying to measure the duty cycle on the 4WD solenoid that DesertDog used for the SG-II. This ought to be interesting!

 

[quote=wptski;202139]"without poor driving conditions"-good luck with this definition as traction varies in real world conditions regardless of what the outdoor weather is.

 

[quote=Billyk;202306]Somebody posted that there is rear torque up to 25mph. You and DesertDog claim that there's always some loss of traction to cause rear wheel torque. If this is true, I should be able easily see some duty cycle of the 4WD solenoid on wet pavement. A full throttle take off from a dead stop should also generate rear wheel torque too. I question if there really is rear wheel torque on dry pavement with a light throttle and at a steady crusing speed.

I just want proof, either way. Makes no difference to me if I'm wrong.

A bit of work but I could always put my front end on jack stands, jack up one rear wheel and "make" sure to shut off the AdvanceTrac. That should put 100% torque to the jacked up rear wheel. This would be my last resort!