2.5 Hybrid: P0811 code OBD2

[Thex]

So I had this pop on me on my Thanksgiving road trip from KS to NH . At aprox 3300 miles on the OD and 100 miles from my destination, the CEL had appeared after a quick acceleration. I was able to make it to my destination with the truck performing like nothing had occurred. When I got to NH, I checked and saw the 0811 code. I immediately came to this forum and found this thread. The next day I did a couple of quick accelerations and when I turned the truck back on, the CEL was gone.
The CEL came back on during my return trip, 5200 miles, 6 hours away from home. Again, the CEL lit up after a quck acceleration (I was watching.) Again, the truck continued to perform as if nothing was wrong, and I verified I could not exceed 75% power. I called my KS dealer during the drive, confirmed I could still drive it and made an appointment just to "have it on the record." Sure enough, the CEL was off the next day.
Two weeks later - yesterday - I took it in for its appointment. They mentioned that the computer modules had to be reflashed and were performing that when the ABS module bricked. They are now waiting on FORD for a good file to flash.....

I will report back once I found out more, but I am a little worried for the bricked ABS. Hopefully they can flash it with no issues.

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[onetequilatwo]

So I had this pop on me on my Thanksgiving road trip from KS to NH . At aprox 3300 miles on the OD and 100 miles from my destination, the CEL had appeared after a quick acceleration. I was able to make it to my destination with the truck performing like nothing had occurred. When I got to NH, I checked and saw the 0811 code. I immediately came to this forum and found this thread. The next day I did a couple of quick accelerations and when I turned the truck back on, the CEL was gone.
The CEL came back on during my return trip, 5200 miles, 6 hours away from home. Again, the CEL lit up after a quck acceleration (I was watching.) Again, the truck continued to perform as if nothing was wrong, and I verified I could not exceed 75% power. I called my KS dealer during the drive, confirmed I could still drive it and made an appointment just to "have it on the record." Sure enough, the CEL was off the next day.
Two weeks later - yesterday - I took it in for its appointment. They mentioned that the computer modules had to be reflashed and were performing that when the ABS module bricked. They are now waiting on FORD for a good file to flash.....

I will report back once I found out more, but I am a little worried for the bricked ABS. Hopefully they can flash it with no issues.

Good luck and keep us posted.

 

[Thex]

Just got a call from the dealer - they are still waiting on FORD to send the file. They have not received a response from FORD for the request.

 

[NJBob]

I read somewhere, manual I believe, relearn occurs if negative cable disconnected from 12v battery. So can we place 12v temp battery in parallel when swapping battery? But couldn't be done most of time.

My son used to work at advanced auto parts. They would use a jump pack connected to the cig lighter socket when swapping a battery. They prob don't do that now.

 

[mav47]

Hadn't checked this thread in a while, and found there are some more postings from folks with this issue (damper/clutch slippage, reduced power to 75%, and P0811 CEL, which turns off within a day or so)

I posted on this thread that I had the clutch/damper slippage a few times, with accompanying CEL and the issue then disappeared until I had it happen another time after which I took the truck to Ford Service, they couldn't reproduce the slippage nor the CEL so they returned the truck after a week and said to come back if it happened again.

I'd like to note that the slippage ended up being noticeably less severe each subsequent time. The first occasion was quite bad with very obvious slippage, the last time slippage was barely noticeable, but the CEL did come on along with that 75% power restriction.

I have since put another 12,000 miles on my Maverick (currently at 18k on the odometer) with zero issues.

This has me convinced that the issue is simply that the friction surfaces of the damper/clutch between the engine and the transaxle need to "bed in". This bedding-in ONLY happens when the clutch is slipping, and as it does so it increases its friction coefficient which makes it less likely to slip the next time.

It seems my clutch pack is at the point where it won't slip at all under any engine load and the issue appears resolved

For others that have seen this issue:

Before pulling the whole engine and transmission and replacing said damper/clutch (which is a pretty big deal) I would now recommend "a holding pattern" for a while, letting it slip a few times and seeing the CEL come on and go off again.

After a few times, you may well find that the problem goes away as the clutch has bedded in and you'll never see the issue come up again!

 

[GPSMan]

"This DTC sets when the engine speed measured by the PCM exceeds the engine speed measured at the transmission."


"Attempt to duplicate the issue under high acceleration (max engine load) while monitoring the PID s. The damper can slip under high loads
due to oil saturation. If issue returns then REPLACE the damper and INSPECT the transmission input shaft for damage."

HTH

 

[mamboman777]

Hadn't checked this thread in a while, and found there are some more postings from folks with this issue (damper/clutch slippage, reduced power to 75%, and P0811 CEL, which turns off within a day or so)

I posted on this thread that I had the clutch/damper slippage a few times, with accompanying CEL and the issue then disappeared until I had it happen another time after which I took the truck to Ford Service, they couldn't reproduce the slippage nor the CEL so they returned the truck after a week and said to come back if it happened again.

I'd like to note that the slippage ended up being noticeably less severe each subsequent time. The first occasion was quite bad with very obvious slippage, the last time slippage was barely noticeable, but the CEL did come on along with that 75% power restriction.

I have since put another 12,000 miles on my Maverick (currently at 18k on the odometer) with zero issues.

This has me convinced that the issue is simply that the friction surfaces of the damper/clutch between the engine and the transaxle need to "bed in". This bedding-in ONLY happens when the clutch is slipping, and as it does so it increases its friction coefficient which makes it less likely to slip the next time.

It seems my clutch pack is at the point where it won't slip at all under any engine load and the issue appears resolved

For others that have seen this issue:

Before pulling the whole engine and transmission and replacing said damper/clutch (which is a pretty big deal) I would now recommend "a holding pattern" for a while, letting it slip a few times and seeing the CEL come on and go off again.

After a few times, you may well find that the problem goes away as the clutch has bedded in and you'll never see the issue come up again!

What you say does make some sense, but I don't think any engine codes should be popping during break in. Moreso, it's recommended to drive the truck without full throttle acceleration during break in... Not floor it to help the clutch settle. *Septical*

 

[GPSMan]

I do notice a pattern.
People who are "flooring it" are the people having this problem.

Now, I'd like to be able to "floor it" if I really needed to, like if there was an exploding volcano behind me or something (West coast, it could happen...). But so far, in the first 3,000 miles, I've not yet had the need to floor it once.

Towing a HEAVY trailer up 7% grade the power was at 60 to 70%.

 

[mav47]

What you say does make some sense, but I don't think any engine codes should be popping during break in. Moreso, it's recommended to drive the truck without full throttle acceleration during break in... Not floor it to help the clutch settle. *Septical*

You are right of course: this issue should not occur at all. Ford needs to install clutch friction surfaces that are ok from the factory and/or increase the spring pressure on the pack, increase the friction surface area, or something along those lines. I would think that Ford is taking notice and will fix this so it doesn't happen going forward. This clutch pack should never slip under any engine torque load.

However, when you have a 'pre-clutch-fix" Hybrid Maverick like I do and are faced with this clutch slippage and some P0811 codes, I much prefer letting this clutch pack bed in with a few full-throttle runs and for the problem to disappear by itself (like it did on mine) versus a Ford dealer pulling out my engine and transaxle, replacing the clutch/damper and reinstalling the whole shebang. With that, there is simply more that can potentially go wrong or cause glitches down the road....!

I am pretty confident that now this clutch doesn't slip under full engine load, it will probably not slip even years down the road.

 

[mamboman777]

You are right of course: this issue should not occur at all. Ford needs to install clutch friction surfaces that are ok from the factory and/or increase the spring pressure on the pack, increase the friction surface area, or something along those lines. I would think that Ford is taking notice and will fix this so it doesn't happen going forward. This clutch pack should never slip under any engine torque load.

However, when you have a 'pre-clutch-fix" Hybrid Maverick like I do and are faced with this clutch slippage and some P0811 codes, I much prefer letting this clutch pack bed in with a few full-throttle runs and for the problem to disappear by itself (like it did on mine) versus a Ford dealer pulling out my engine and transaxle, replacing the clutch/damper and reinstalling the whole shebang. With that, there is simply more that can potentially go wrong or cause glitches down the road....!

I am pretty confident that now this clutch doesn't slip under full engine load, it will probably not slip even years down the road.

The thing I take issue with is... All this would make sense if this were a regular clutch that's meant to slip. This is a breakaway clutch. It's only supposed to slip if something goes wrong.

 

[DreamWeaver21]

I do notice a pattern.
People who are "flooring it" are the people having this problem.

Now, I'd like to be able to "floor it" if I really needed to, like if there was an exploding volcano behind me or something (West coast, it could happen...). But so far, in the first 3,000 miles, I've not yet had the need to floor it once.

Towing a HEAVY trailer up 7% grade the power was at 60 to 70%.

Mine came on for the 2nd time at 6400km and only 57% "Accelerator Pedal Position" so while I was moving right along, I wasn't exactly flooring it or anything.

 

[GPSMan]

Hmm....

But could it have been 57% on the way down from something higher just prior?

 

[GPSMan]

Mine came on for the 2nd time at 6400km and only 57% "Accelerator Pedal Position" so while I was moving right along, I wasn't exactly flooring it or anything.

I don't have FORScan but looks like a neat item to have. I have something called ScanGaugeIII. Maybe you've seen it. Mine is only for dispLaying digital gauges. I have half the ones on your list. I can manually program additional gauges, but I need the hexadecimal codes or "addresses" for each. Will Forscan tell you this level of data, for say TFT or G_Speed?

looks like this: Thank You

 

[Thex]

Well, no update from the Dealer. No call from them either. I did call and leave a message.... Ford app shows 12 vehicle alerts now. Hoping @Ford Motor Company is watching this thread and can help escalate...

 

[Thex]

Dealer just called. Ford asked them to reflash with a different computer, failed again at the abs module/Computer, whatever you want to call it. They ordered a new ABS module, part is ordered however there is no ETA on availability. They can say vehicle down which should move it to the top of the list however with limited parts availability I could be without my truck for a long time.

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