avidmotion
New member
wow after reading all that I think I am all researched up on the subject now!
“AWD off” message on long drive
- Thread starter jus2quik
- Start date
Good INFO on the AWD & MORE! Z
The Rear Differential Unit on the police version uses a fluid-filled clutch pack, while the retail version uses dry clutches. The fluid-filled RDU can withstand more severe duty.
Both the PI Sedan and PI Utility operate as FWD vehicles until wheel slip is detected. Only then does power transfer to the rear wheels. Of the most importance, the transaxle with water-cooled (police-only) AWD Power Transfer Unit was located. And then the rear axle mounted Active Torque Coupling Unit attached to the Rear Differential Unit was pointed out. On these AWD vehicles, power is continually fed to both the front half-shafts and the rear driveshaft. The driveshaft is constantly engaged and rotating even if power is not fed to the rear wheels.
The Front Wheel Drive system and the Power Transfer Unit send torque back to the rear clutch pack all the time. Any time the vehicle is moving, the driveshaft to the rear is turning. The Active Torque Coupling mounted on the Rear Differential Unit only passes on torque when needed. But it is literally right there when it is needed.
The ATC/RDU used on the Police Interceptors uses fluid-filled “wet” clutch packs. The retail Taurus and Explorer use dry clutches. The PI wet clutches can withstand higher temps and withstand higher temps longer than the retail unit. The ATC and RDU are not field serviceable. In case of a problem with either system, the whole unit is replaced.
http://www.hendonpub.com/resources/article_archive/results/details?id=5091
The Rear Differential Unit on the police version uses a fluid-filled clutch pack, while the retail version uses dry clutches. The fluid-filled RDU can withstand more severe duty.
Both the PI Sedan and PI Utility operate as FWD vehicles until wheel slip is detected. Only then does power transfer to the rear wheels. Of the most importance, the transaxle with water-cooled (police-only) AWD Power Transfer Unit was located. And then the rear axle mounted Active Torque Coupling Unit attached to the Rear Differential Unit was pointed out. On these AWD vehicles, power is continually fed to both the front half-shafts and the rear driveshaft. The driveshaft is constantly engaged and rotating even if power is not fed to the rear wheels.
The Front Wheel Drive system and the Power Transfer Unit send torque back to the rear clutch pack all the time. Any time the vehicle is moving, the driveshaft to the rear is turning. The Active Torque Coupling mounted on the Rear Differential Unit only passes on torque when needed. But it is literally right there when it is needed.
The ATC/RDU used on the Police Interceptors uses fluid-filled “wet” clutch packs. The retail Taurus and Explorer use dry clutches. The PI wet clutches can withstand higher temps and withstand higher temps longer than the retail unit. The ATC and RDU are not field serviceable. In case of a problem with either system, the whole unit is replaced.
http://www.hendonpub.com/resources/article_archive/results/details?id=5091
Went to a buddies shop and we ran codes and checked all connections ,all looked good and had good continuity through wires ,rechecked fluids and called it a day.
Just went on another 3 hour drive today since my last “AWD off” message,about 60 miles in the message came on so I pulled over into some grass and sure as hell just FWD,let it cool like manual says and tested in grass again,awd back up and working. Another 60 miles or so of 80+ mph dry highway. Message came back on .
Went back to reading info on the RDU itself,found info stating that when the rdu overheats the clutches first lock up to try and cool itself down,if this is the case then when I immediately pulled over to check wouldn’t the clutches in the RDU possibly be locked in AWD not disengaged ? I usually can figure things out like this so it’s hard for me to give up and just drop everything off at the dealer but I guess it’s time .Wish I could just talk to a tech face to face that knows what it could possibly be . Again thanks all ,hopefully this thread will help someone with a similar problem .I know 8 can’t be the only one this has happened to .
Just went on another 3 hour drive today since my last “AWD off” message,about 60 miles in the message came on so I pulled over into some grass and sure as hell just FWD,let it cool like manual says and tested in grass again,awd back up and working. Another 60 miles or so of 80+ mph dry highway. Message came back on .
Went back to reading info on the RDU itself,found info stating that when the rdu overheats the clutches first lock up to try and cool itself down,if this is the case then when I immediately pulled over to check wouldn’t the clutches in the RDU possibly be locked in AWD not disengaged ? I usually can figure things out like this so it’s hard for me to give up and just drop everything off at the dealer but I guess it’s time .Wish I could just talk to a tech face to face that knows what it could possibly be . Again thanks all ,hopefully this thread will help someone with a similar problem .I know 8 can’t be the only one this has happened to .
Also I never got this message or situation before my tune a few months ago,but I couldn’t imagine that would have anyth8ng to do with anything unless somehow it changed how aggressive the RDU locks up somehow.I imagine if voltage has changed maybe the clutches are dragging more that normal causing heat buildup ,maybe?
Also can’t find a temp sensor mentioned in the RDU itself,only have two wires running into the housing that I can see.
Also can’t find a temp sensor mentioned in the RDU itself,only have two wires running into the housing that I can see.
That’s what makes it seem odd that they say “if it overheats “ the AWD off message will pop up,How does it know that it’s overheated if there is not a temp sensor of some kind in the RDU?
there must be a gremlin or something at work in the harness ,maybe the dealer can figure it out ,I’ll post back what they found or what they do to fix it
there must be a gremlin or something at work in the harness ,maybe the dealer can figure it out ,I’ll post back what they found or what they do to fix it
Lease vehicle with 20k miles
GH tune ,plugs,tstat and drop in filter
Recently changed fluids
RDU looks like it’s been replaced,tool marks on all bolts holding it in ,when I checked fluid looked new and fresh.
Did my best to do a good PTU fluid change
Want to learn “ how” this car works ,hate just dropping it off at dealership,I’m a hands on mechanic type ,had many cars and off-road rigs that required study and hard work ,but if this is a dealer issue I better let them have a crack at it . I have a 100k bumper to bumper extended warranty and have already set it back to stock and put the 2 bar MAP back in . I’m good with swapping parts,welding and modding brackets,etc but just lack in electrical things in depth .
GH tune ,plugs,tstat and drop in filter
Recently changed fluids
RDU looks like it’s been replaced,tool marks on all bolts holding it in ,when I checked fluid looked new and fresh.
Did my best to do a good PTU fluid change
Want to learn “ how” this car works ,hate just dropping it off at dealership,I’m a hands on mechanic type ,had many cars and off-road rigs that required study and hard work ,but if this is a dealer issue I better let them have a crack at it . I have a 100k bumper to bumper extended warranty and have already set it back to stock and put the 2 bar MAP back in . I’m good with swapping parts,welding and modding brackets,etc but just lack in electrical things in depth .
I was curious if you ever replaced the Tires! I was able to obtain some Good INFO Directly from WSM! Z 
The AWD system consists of a PTU , driveshaft, front and rear halfshafts, AWD relay module, PCM which includes the AWD control logic and an ATC solenoid located in the rear axle. Based on inputs to the PCM, the PCM sends a command to the AWD relay module. The amount of torque sent to the rear wheels is controlled by the AWD relay module sending a PWM duty cycle to the ATC solenoid.
The PCM provides the brake system with its current clutch command torque level and determines wether or not the brake system may take command of the AWD clutch.
If the compact spare tire is installed, the AWD system may disable automatically and enter FWD only mode to protect driveline components. This condition may be indicated by an AWD OFF message in the message center.
If there is an AWD OFF message in the message center from using the compact spare tire, this indicator should turn off after reinstalling the repaired or replaced normal road tire and cycling the ignition OFF and ON. It is recommended to reinstall the repaired or replaced road tire as soon as possible. Major dissimilar tire sizes between the front and rear axles could cause the AWD system to stop functioning and default to FWD or damage the AWD system.
AWD faults will be indicated by the powertrain malfunction (wrench) message center warning indicator in the IPC as well as the Check AWD message center warning indicator in the message center.
The PCM provides the brake system with its current clutch command torque level and determines wether or not the brake system may take command of the AWD clutch.
Heat Protection ( RDU )
During very extreme off-road operation, the AWD system utilizes a heat protection mode to protect the AWD clutch from damage. If the AWD system detects an overheat condition, it enters a locked mode. If the heat in the AWD system continues to rise once in the locked mode, the PCM disables the ATC solenoid. This condition may be indicated by an AWD OFF message in the message center. To resume normal AWD function as soon as possible, stop the vehicle in a safe location and stop the engine for at least 10 minutes. After the engine is restarted and the AWD system has adequately cooled down, the AWD OFF message will turn off and normal AWD operation will return. In the event the engine is not stopped, the AWD OFF message will turn off when the system cools and normal AWD operation returns.
Visual Inspection Chart
Mechanical Electrical
ATC solenoid (part of rear axle)
PTU
RDU
Halfshafts and CV joints
Driveshaft and U-joints
Fluid leaks
Wheel/tire size and brand
Matching tire size and brand
Tire pressure
BJB fuse 70 (15A)
AWD relay
Wiring harness
Connector(s)
Circuitry
PCM
The AWD system consists of a PTU , driveshaft, front and rear halfshafts, AWD relay module, PCM which includes the AWD control logic and an ATC solenoid located in the rear axle. Based on inputs to the PCM, the PCM sends a command to the AWD relay module. The amount of torque sent to the rear wheels is controlled by the AWD relay module sending a PWM duty cycle to the ATC solenoid.
The PCM provides the brake system with its current clutch command torque level and determines wether or not the brake system may take command of the AWD clutch.
If the compact spare tire is installed, the AWD system may disable automatically and enter FWD only mode to protect driveline components. This condition may be indicated by an AWD OFF message in the message center.
If there is an AWD OFF message in the message center from using the compact spare tire, this indicator should turn off after reinstalling the repaired or replaced normal road tire and cycling the ignition OFF and ON. It is recommended to reinstall the repaired or replaced road tire as soon as possible. Major dissimilar tire sizes between the front and rear axles could cause the AWD system to stop functioning and default to FWD or damage the AWD system.
AWD faults will be indicated by the powertrain malfunction (wrench) message center warning indicator in the IPC as well as the Check AWD message center warning indicator in the message center.
The PCM provides the brake system with its current clutch command torque level and determines wether or not the brake system may take command of the AWD clutch.
Heat Protection ( RDU )
During very extreme off-road operation, the AWD system utilizes a heat protection mode to protect the AWD clutch from damage. If the AWD system detects an overheat condition, it enters a locked mode. If the heat in the AWD system continues to rise once in the locked mode, the PCM disables the ATC solenoid. This condition may be indicated by an AWD OFF message in the message center. To resume normal AWD function as soon as possible, stop the vehicle in a safe location and stop the engine for at least 10 minutes. After the engine is restarted and the AWD system has adequately cooled down, the AWD OFF message will turn off and normal AWD operation will return. In the event the engine is not stopped, the AWD OFF message will turn off when the system cools and normal AWD operation returns.
Visual Inspection Chart
Mechanical Electrical
ATC solenoid (part of rear axle)
PTU
RDU
Halfshafts and CV joints
Driveshaft and U-joints
Fluid leaks
Wheel/tire size and brand
Matching tire size and brand
Tire pressure
BJB fuse 70 (15A)
AWD relay
Wiring harness
Connector(s)
Circuitry
PCM
Dropped Taurus off at the dealership today,first thing the guy says is that the tires are different make front and rear and it prob won’t be covered,they are the same size,age and air pressure ,the dealership where we bought the car bought two sets of tires for two Taurus cars and the tech mixed the tires up ,brand new tires but different brands and they want to possibly deny the warranty claim.
Agreed ^^^ It sounds like they want to profit on some new rubber!
I would also try to perform a Battery reset to clear the PCM memory and monitor for any changes..
I think locating a reputable Lincoln dealer is ideal especially if they cannot or won't troubleshoot it properly IMO! Z
https://youtu.be/hZAsoqmqhdM
I would also try to perform a Battery reset to clear the PCM memory and monitor for any changes..
I think locating a reputable Lincoln dealer is ideal especially if they cannot or won't troubleshoot it properly IMO! Z
https://youtu.be/hZAsoqmqhdM