Big Blue's Transformation

[Gary Lewis]

6,000 lbs (half capacity) is still close to Big Blue's actual weight, isn't it?

My truck is loaded with crap and tare is around 6,600 with full tanks.

I know flatbed winches are hydraulic and much more powerful but you might be amazed just how easy it is to move a 4x4 truck. Even one that is wrapped around a tree or has no wheel that turns.

I don't have a breakout box. But I really don't think one is needed since we are just talking about the one pin - #4 - and I have that one extended to a 1-pin connector.

But several things about the page confuse me. For instance, what does the "(M)" mean after PTO?

The next column appears to say that the #'s in the following column are DV voltages and they are in the order of "Off" then "On", presumably for the PTO function. But then it shows that the Off voltage will be .1V in all cases and the "On" voltage will be "Off".

That is really confusing as the diagram from earlier in the document shows taking Pin 4 to battery voltage to turn the PTO function on. So what does "Off" mean?

[Gary Lewis]

6,000 lbs (half capacity) is still close to Big Blue's actual weight, isn't it?

My truck is loaded with crap and tare is around 6,600 with full tanks.

I know flatbed winches are hydraulic and much more powerful but you might be amazed just how easy it is to move a 4x4 truck. Even one that is wrapped around a tree or has no wheel that turns.

BB rolls pretty easily on pavement. But when aired down to 15 PSI and winching not only up hill but over a berm, like we did in CO last fall, it takes a bit more. The 12K winch was picked for overkill and I sure hope I'll never need its full capacity.

But I do want to be able to use it should I need to do so. So I want to fuse it appropriately. Now, if I could just figure out what that is...

[Gary Lewis]

BB rolls pretty easily on pavement. But when aired down to 15 PSI and winching not only up hill but over a berm, like we did in CO last fall, it takes a bit more. The 12K winch was picked for overkill and I sure hope I'll never need its full capacity.

But I do want to be able to use it should I need to do so. So I want to fuse it appropriately. Now, if I could just figure out what that is... http://www.garysgaragemahal.com/uploads/6/5/8/7/65879365/thinking-26_orig.jpg

I'm been doing research on the PTO function and it looks to me like what it does is to turn off monitoring of certain emissions things for a period of time.

In the to-be-monitored parameter below, BITMAP_KAM_1, you can see that one of the bits is labeled "PTO (Power Take Off) is active (disable affected monitors)". I believe that bit gets set when the PTO input goes high, and I'm going to test that in a bit.

And when that bit gets set the table below shows what happens. Each bit that is turned on in Power Take Off (PTO) Affected Monitors turns monitoring off for that function for the time shown in Power Take Off Hold Time. For instance, Bit 0 turns monitoring the cat off.

So in both Bill's tune, which is Value 2, and mine (Value) we don't tell it to turn anything off as there are no bits set, but if there were the monitoring would be disabled for 120 seconds.

I cannot find any other parameters that PTO affects, nor any value of idle RPM that should increase when PTO is turned on. But I've asked on Decipha's forum to see if I'm missing something.

And now I'm going to test the theory set out above by data logging lots of things, inc BITMAP_KAM_1 while I play with the PTO input...

[Gary Lewis]

I'm been doing research on the PTO function and it looks to me like what it does is to turn off monitoring of certain emissions things for a period of time.

In the to-be-monitored parameter below, BITMAP_KAM_1, you can see that one of the bits is labeled "PTO (Power Take Off) is active (disable affected monitors)". I believe that bit gets set when the PTO input goes high, and I'm going to test that in a bit.

And when that bit gets set the table below shows what happens. Each bit that is turned on in Power Take Off (PTO) Affected Monitors turns monitoring off for that function for the time shown in Power Take Off Hold Time. For instance, Bit 0 turns monitoring the cat off.

So in both Bill's tune, which is Value 2, and mine (Value) we don't tell it to turn anything off as there are no bits set, but if there were the monitoring would be disabled for 120 seconds.

I cannot find any other parameters that PTO affects, nor any value of idle RPM that should increase when PTO is turned on. But I've asked on Decipha's forum to see if I'm missing something.

And now I'm going to test the theory set out above by data logging lots of things, inc BITMAP_KAM_1 while I play with the PTO input...

And here's the proof that at least I'm getting the ECU to recognize the PTO input.

The red square wave is the BITMAP_KAM_1 output, and you can see that it goes high 4 times, which is how many times I hit the PTO input with my test light. And as you can see on the left, where the white vertical line is the value of that parameter is 32.

From the previous post the PTO status is Bit 5. And when you turn the binary number of 00100000 into decimal it is 32. So none of the flags are set save for PTO since the value is zero at all other times.

And you can see that the Desired RPM didn't change due to PTO, although it was still at 736 due to the ECT being only 104F.

[Gary Lewis]

And here's the proof that at least I'm getting the ECU to recognize the PTO input.

The red square wave is the BITMAP_KAM_1 output, and you can see that it goes high 4 times, which is how many times I hit the PTO input with my test light. And as you can see on the left, where the white vertical line is the value of that parameter is 32.

From the previous post the PTO status is Bit 5. And when you turn the binary number of 00100000 into decimal it is 32. So none of the flags are set save for PTO since the value is zero at all other times.

And you can see that the Desired RPM didn't change due to PTO, although it was still at 736 due to the ECT being only 104F.

With PTO not doing what I was looking for I may have found another option: Low Voltage Idle Adder.

As shown below, both my tune and Bill's tune have no provision to raise the idle RPM if the battery voltage gets "low". But I could easily put a curve in there that would raise the idle. However, as yet I've not found out what voltage is considered "low".

But there is a parameter called "Charging System Lowest Voltage to Indicate Bad" and one called "Charging System Lowest Voltage to Indicate Good". Both of our tunes have bad set to 11V and good to 12.5V. So I'm wondering if the Low Voltage Idle Air Adder kicks in at 11.0 and out at 12.5.

Seems like I could test that pretty easily by writing a new table in that actually raises the desired idle RPM and then turning the air compressor on.

Thoughts? Better ideas?

[85lebaront2]

With PTO not doing what I was looking for I may have found another option: Low Voltage Idle Adder.

As shown below, both my tune and Bill's tune have no provision to raise the idle RPM if the battery voltage gets "low". But I could easily put a curve in there that would raise the idle. However, as yet I've not found out what voltage is considered "low".

But there is a parameter called "Charging System Lowest Voltage to Indicate Bad" and one called "Charging System Lowest Voltage to Indicate Good". Both of our tunes have bad set to 11V and good to 12.5V. So I'm wondering if the Low Voltage Idle Air Adder kicks in at 11.0 and out at 12.5.

Seems like I could test that pretty easily by writing a new table in that actually raises the desired idle RPM and then turning the air compressor on.

Thoughts? Better ideas?

Gary, item for your edification. It is going to take a pretty good load for quite a while to pull even one of those Optimas down to 11 volts and since the EEC is monitoring either pin #55 (KAPWR) or pins #71 or #97 (VPWR) (key on) it is going to work from system power. Same on Darth, it takes a while if the alternator quits or has low output before that Motorcraft Group 65 monster gets below 11 volts.

I can't think of a way to have the EEC monitor only the alternator output without interfering with charging the battery and powering the rest of the vehicle. If there were a way for the EEC to monitor the charge light that might work.

[Gary Lewis]

With PTO not doing what I was looking for I may have found another option: Low Voltage Idle Adder.

As shown below, both my tune and Bill's tune have no provision to raise the idle RPM if the battery voltage gets "low". But I could easily put a curve in there that would raise the idle. However, as yet I've not found out what voltage is considered "low".

But there is a parameter called "Charging System Lowest Voltage to Indicate Bad" and one called "Charging System Lowest Voltage to Indicate Good". Both of our tunes have bad set to 11V and good to 12.5V. So I'm wondering if the Low Voltage Idle Air Adder kicks in at 11.0 and out at 12.5.

Seems like I could test that pretty easily by writing a new table in that actually raises the desired idle RPM and then turning the air compressor on.

Thoughts? Better ideas?

Well, I'm half way there - I got it to raise the idle RPM but not drop it back down when the voltage came back.

But first, a "funny" story. Apparently when you pull the ECU fuse to wipe its memory you should put it back before trying to start the truck.

But after replacing the fuse it started easily. And I'd made two changes to the tune. First, I set the Charging System Lowest Voltage To Indicate Bad to 12.0V, but left the voltage for Good at 12.5. Second, I changed the Low Voltage Idle Air Adder table as shown below. My thinking was that I'd get 96 RPM immediately when the voltage goes low, and then I'll get a nice smooth increase of another 400 RPM over the next 254 seconds.

But that's not quite what happened so my thinking is wrong somewhere. In the chart below the battery voltage was rocking along at 13.9ish and when the desired idle RPM got down to 640 I turned the air compressor on. As you can see, the voltage went south in a hurry, and when it got down to 12.0V the desired idle RPM went to first 736, which is +96, and then to 784, which is +144. Not +200 at 2 seconds, but just another +48 over the initial +96.

But it never came back down from 784. In fact, until I let it sit for a few minutes not running it didn't come back down on restart.

So, what am I missing?

[Gary Lewis]

Gary, item for your edification. It is going to take a pretty good load for quite a while to pull even one of those Optimas down to 11 volts and since the EEC is monitoring either pin #55 (KAPWR) or pins #71 or #97 (VPWR) (key on) it is going to work from system power. Same on Darth, it takes a while if the alternator quits or has low output before that Motorcraft Group 65 monster gets below 11 volts.

I can't think of a way to have the EEC monitor only the alternator output without interfering with charging the battery and powering the rest of the vehicle. If there were a way for the EEC to monitor the charge light that might work.

Bill - As you can see on the chart, the voltage goes south in a hurry when the air compressor comes on. (I was running the A/C with the blower on High as well.) So with the threshold set to 12.0V it took 10 seconds to hit 12.0 and another second for the desired idle to go up 96 R's and then another second to go up another 48 RPM. And for some reason it stopped going up at that point.

So there's something wrong with my understanding of how that table works. But I think this approach will work if I can get my head around the table and get the RPM to come back down when the load goes away. So can you help me understand?

[85lebaront2]

Bill - As you can see on the chart, the voltage goes south in a hurry when the air compressor comes on. (I was running the A/C with the blower on High as well.) So with the threshold set to 12.0V it took 10 seconds to hit 12.0 and another second for the desired idle to go up 96 R's and then another second to go up another 48 RPM. And for some reason it stopped going up at that point.

So there's something wrong with my understanding of how that table works. But I think this approach will work if I can get my head around the table and get the RPM to come back down when the load goes away. So can you help me understand?

Don't forget you gave the computer a lobotomy and it takes a bit for it to get back where it was.

[Gary Lewis]

Don't forget you gave the computer a lobotomy and it takes a bit for it to get back where it was.

Good point. So I'm going to drive it a bit with the tune that's in it and will cycle the air compressor a few times to see what happens.

In fact, we are planning some kind of trip on Tuesday to take the truck out, so maybe miles and starts will help it regain its memory.

But I'm still quite confused as to why it only added 144 RPM to the base of 640. At 1 second we were supposed to get +96 RPM and at 2 seconds +200 RPM. But we only got +144 RPM and it stayed there. That's the amount of increase we should have gotten at 1.46 seconds.

So I'm seeing two problems with this. First, that the desired idle RPM didn't continue to increase until the battery voltage got above the "good" threshold of 12.5V. Second, that once the battery voltage did exceed the good threshold that the desired RPM didn't come back to the base of 640 RPM.

As said, there's something I really don't understand about that table.