Engine/Transmission (1998.5 - 2002) Anatomy of an APPS

[JLandry]

John,



Just to certain you understand MY opinion is this is not quite yet plug and play.

Understood!



At this point I'm interested in acquiring a WIlliams APPS to test and validate for correct function, then keep it (or the OEM APPS) as a spare in my truck's emergency box (along with other failure prone parts).



I occasionally tow a travel trailer in remote areas (like Death Valley) and I'd hate to experience an APPS failure out in the middle of no-place with limited parts availability. That could ruin a vacation in a hurry.



Up until now the cost of the OEM APPS has kept me from carrying one as an emergency spare. Ditto on a VP44 injection unit, so I'm anxious to see what you guys come up with for that!



Thanks for your comments and insight.



John L.

 

[mhenon]

Mike,



Thanks for the speedy come back.



Regarding which Williams Controls part number to buy, here's my take on it after carefully studying their catalog last night...



The Williams APPS "kit" p. n. 132034 does indeed include the APPS we need and the wiring harness, *but* it also includes several other items we don't need for a straight OEM APPS swap and it costs $149. 55 (on the Williams Control web site). P. n. 131973 contains only the APPS and some screws, so you still need wiring harness p. n. 131165, but those two items added together costs less at only $120. 95, so that seems like the better way to go. But certainly buying p. n. 132034 is an acceptable alternative, albeit a bit more expensive.



OK, there's where you have me confused.



Unless I'm mistaken in my studies of the pictures in this thread and the Williams Controls catalog, the Williams APPS has a recepticle on it that the Williams wiring harness plugs into. Put another way, the Williams APPS is not hard wired. Please keep in mind I've never seen a Williams APPS in person. Now assuming you've modified a Williams wiring harness to connect from the Williams APPS directly to the stock (unmodified in any way) engine wiring harness but clipping off the supplied Weatherpack connectors and instaling a single Deutsch 6-pin connector in its place, why would you need a seperate "jumper" harness and have any problem reinstalling either an OEM or Williams APPS in the future?



This is the part I wasn't clear on.



Questions:



1. Is there a way to make this idle voltage adjustment you described on the bench using an Ohm meter? Could I adjust for lowest resistance and then back off the internal stop as you did?



2. Can you please reconfirm these are the wiring connections you're currently using for the Williams APPS (this is what Bob Weis was confirming earlier in the thread after you reported success and I'm not sure I saw you give a black-and-white confirmation this is it). I ask because I saw confusion about how to hook up the IVS component of the Williams APPS.



Williams APPS "A" White wire to OEM 4 black yellow wire (Ground)

Williams APPS "B" Black wire to OEM 3 light blue black wire (Signal)

Williams APPS "C" Red wire to OEM 5 dark blue white wire (5 volt)



Williams IVS "A" Orange wire to OEM 1 black light blue wire (Ground)

Williams IVS "B" Blue wire to OEM brown orange wire (Idle)

Williams IVS "C" Green wire to OEM 2 light green dark blue wire (Throttle or "Not Idle")



Thanks again!



John L.

Looks like you have the Williams wiring correct above. The voltage adjustment needs to take place after you install the Williams sensor in the OEM bellcrank. Just back off on the idle stop screw until you get a suitably low voltage. I couldn't get mine to go lower than . 634 volts. As to how the wiring attaches to the sensor I now see the confusion there. There is a Weather Pack 6 pin connector from the harness into the sensor. This harness is about 2' long and has a 6 pin connector on one end and two 3 pin connectors on the other. The photo should clear that issue. You also asked why you need a jumper if you were to clip off the two weather packs and install a Deutsch connector. You don't... your way would work perfect. I'm going to make up a few jumpers so folks don't have to clip or fabricate anything. . but it can be done the way you describe.

Just to clarify the photo's. . they show the Williams sensor attached to the pedal assemby and the 6 pin weather pack unplugged from the sensor. The last photo is where the jumpr would go between the weather packs (2) and OEM connector. Hope this helps

Also I agree whole heartedly with the posts above about the experimental nature of what we're doing here. We're all beta testers and need to be sure this stuff stands the test of time.

Mike

 

[mhenon]

I'm going to play with something this week (if I find the time) that "might" end the IVS thing permanently. Way back when we were working on VP44 issue's some of the posts suggested that the VP's were seizing after long uphill pulls (towing heavy) just as the driver would hit the crest and let off the pedal. The theory was the VP44 doesn't fuel with rpm's above idle and foot off the pedal. This lack of fuel stopped cooling, lubricating fuel from getting to the rotor and BAM. . seized injector pump. I'm not arguing whether that is totally correct or not but I did try to adjust my idle set screw on the bellcrank to prevent the engine from ever coming to a complete idle. I actually ran it that way for awhile but decided against it and adjusted the idle back to normal. what I had done (without realizing it of course) was to prevent the IVS from ever triggering the internal relay to idle. The engine was always in accelerate. . even though just barely when I let off the pedal. The part I can't remember is. . did I ever try to start the engine in that condition. My memory says I did and it started fine but don't bet a penny on my memory.

Anyway if this works I think everyone can see the implications. Turn the set screw until your engine trickles slightly above idle (825rpm vs 800) and the IVS circuit is froze. If you want to get serious put a jumper between "gound" and "accelerate" in the OEM wiring bundle and the ECM could never even accidently detect idle (a spike from the APPS).

Anyone feeling brave go ahead and try it. I'll try mine when I get the chance. With the weather pack connectors on my OEM wiring it would be simple for me to pull the connector that goes to IVS and install a jumper completely eliminating the IVS circuit. I'll let you know how it goes!

Mike

OK... so here's another great idea gone bad. Thought there might be a way to bypass the IVS altogether but it didn't work. It would work for a while but once the engine was shut down the ECM would remember the last idle voltage and use that as the new start-up idle voltage.

I was first able to trigger the IVS switch at . 750 volts. Passed that point the IVS was in the accelerate mode. Great. . it works! Not so fast! When the engine was restarted, . 750v was now at idle voltage and i had to re-adjust up to like . 785v to trigger IVS. I tried this several times with the same results so gave up. This Cummins ECM is pretty smart (it's like it knew what I was trying to do). I didn't continue up in voltage as I'm sure at some point I would have triggered a "High Idle Voltage" MIL.

Anyway. . it looked good on paper!!!

Mike

 

[KarlC]

1. Is there a way to make this idle voltage adjustment you described on the bench using an Ohm meter? Could I adjust for lowest resistance and then back off the internal stop as you did?

John, I think you could do bench adjustment using a 5-volt power supply and a voltmeter. Connect the positive and negative leads of the power supply to the ends of the APPS potentiometer and measure the voltage coming out of the APPS wiper with respect to the power supply negative terminal. (That's the technique I used when I measured the characteristics of the APPS for post 151 of this thread. ) Then make the idle voltage adjustment.



Karl

 

[JLandry]

John, I think you could do bench adjustment using a 5-volt power supply and a voltmeter. Connect the positive and negative leads of the power supply to the ends of the APPS potentiometer and measure the voltage coming out of the APPS wiper with respect to the power supply negative terminal. (That's the technique I used when I measured the characteristics of the APPS for post 151 of this thread. ) Then make the idle voltage adjustment.



Karl

Thanks Karl.



I think I finally understand the adjustment requirements and am looking forward to actually trying it. Everything is on order.



Now I wish I had a spare OEM APPS assembly handy so I could set up and adjust everything up on my workbench without having to remove my working OEM APPS from my truck.



Drive safe,



John L.

 

[Gary - K7GLD]

Thanks Karl.



I think I finally understand the adjustment requirements and am looking forward to actually trying it. Everything is on order.



Now I wish I had a spare OEM APPS assembly handy so I could set up and adjust everything up on my workbench without having to remove my working OEM APPS from my truck.



Drive safe,



John L.

YUP - that's what I did on my version - got the settings done on the bench, installed it on the truck - no problems!

 

[JLandry]

I was having a heck of a time getting the ECM to put the "new" APPS values in the ECM. I thought it was "9. Execute APPS "learn" procedure" also. I think there is something more to it than that.

Bob,



I think I stumbled across something interesting last night while doing some reading, and I'm not sure if any of the rest of you caught this...



Chapter 14 of the Dodge service manual instructs us to do the APPS "learn" procedure ONE time after replacing the APPS or DTC codes might be set.



BUT, in the Williams Controls APPS installation procedure described in the Van Hool Service Service Bulletin No. 1103 (referenced much earlier in this thread), they state:

"The ECM and accelerator pedal must be calibrated when an accelerator pedal is initially installed, when an accelerator pedal is replaced, when a new calibration is downloaded to the ECM, and when the accelerator pedal wiring is being disconnected while the vehicle ignition switch is ON.



To recalibrate the ECM and accelerator pedal, the ignition switch must be in the ON position and then the accelerator pedal must be slowly and fully depressed from idle to full throttle.



Repeat the procedure three times. "​

Interesting... no?



Maybe when there's a large change in the APPS calibration voltage, it simply takes three full "learn" procedures to get the ECM to accept them? This would seem to be consistent with what you've experienced.



Your thoughts?



John L.

 

[Wyomingcowboy]

You guys are absolutely nuts! It is way beyond me to evr consider messing with any of that stuff, but I sure am glad you are not like me! If it proves that i do need an apps i will definitely try this route. Many thanks to all of you who don't go with the flow and search to better the OEM solutions.

TDR rocks!

 

[PRout]

I occasionally tow a travel trailer in remote areas (like Death Valley) and I'd hate to experience an APPS failure out in the middle of no-place with limited parts availability. That could ruin a vacation in a hurry.

Believe it or not, I actually DID experience an APPS failure in Death Valley.

https://www.turbodieselregister.com...-1998-5-2002/105646-drops-idle-vp44-apps.html

Thats a pretty weird feeling dropping down into no mans land with a failing vehicle until you realize its not something that will leave you stranded. Its just a shame DC hasnt come up with an upgraded part to rectify the problem.

Just had to throw that in. Nice job guys, please carry on. The engineers at DC need more potty training.

 

[mhenon]

... The engineers at DC need more potty training.

Phil, This OEM APPS smells like the work of a bean counter rather than an engineer. When you look at the bellcrank assembly. . it comes with adjustment screws for both idle and WOT. Then you look at the DC APPS and find slotted bolts holes for the same adjustment (idle anyway). Why would you need two different adjustments doing the same thing? What I think is the Cummins engineers had a commercial truck/bus APPS (like the Williams) in mind... bolt it on and make minor adjustments at the stop screw. But then some idiot accountant from DC comes along and says" Hey guys look. I've located a POS APPS that will save us $12. 93 per unit on the new Dodge Ram line. AND. . we can sell it for five times that commercial unit". And here we are!!!

Just an up-date on the Williams APPS on my rig. It's still the dead of winter here in Idaho with over 2' of snow on the ground and temps going into the teens. I've been leaving the truck outside at night to cold soak and making several longs runs to get it good and hot. This is exactly when my OEM APPS was failing. . starting cold and getting fully warm. Also been making hard runs climbing hills while loaded (1200lbs of gravel in the bed for traction). Just doing anything I can think of to put a little stress on the system and see if it will throw a code. The cold morning starts and low battery voltages should be the worst from the APPS/ECM perspective.

So far. . all systems are "Go". We need to get a few more brave souls with different year rigs to give this a try and then put lots and lots of miles on them. Time in the field (real world) will be the only test that matters. At this point I have a lot of confidence in the Williams APPS.

Mike

 

[timbo]

I got some news, I've been working on finding Williams products and sorting out the part #s with my supplier to get just the sensor. The web sight with there part#s, it was a little confusing. But i got it narrowed done now! I have one sensor right now that has been the test rig and is going to a buddy on monday. I ordered 5 more last wed. and they should be here in about a week 1/2. I am putting a kit together with instructions so that any one that can read a Digital volt meter can do it. The conversion harness will already be done(soldered, not just crimped) all you will have to do is change sensors, plug it in, and set the ldle voltage using the voltmeter and procedure. I aready have 2 of the 5 sold to local friends, that means i have 3 left for anyone that is interested. Price is going to be around $140. I think thats fair. If anyone is intersested PM me.

 

[rweis]

That is EXACTELY what we need. A way to make them available, reasonably, as plug and play as possible.



GOOD JOB timbo.



What voltage are you telling them to set it to? I have been running . 435 on an auto transmission to see how it goes. I think I am running at the low end of the voltage range. Runs fine though. I think I am going to raise mine to . 500 for the long run though.



I think we probably need to start a new thread called "How to fix your APPS YOURSELF" so someone does not think a 4 year old post does not have valid information in it. Also does not have to wade through the experimentation. It would be fairly descriptive and to the point as well.



There is still some experimentation going on, so be sure to tell them to check this thread. I think the final best solution is going to be the bus APPS and a MS for the IVS. I am going to start working with a fab shop to design and build the MS bracket just to get the IVS out of the circuitry board stage and into a mechanical stage.



A mechanical MS would also tell them if the APPS pot was acting up because it would be a seperate switch. ie APPS failing, NO DOUBT BUT TO CHANGE THE APPS, because it is the ONLY part in that circuit. It removes the question "is it the APPS pot or the IVS circuit?" because there is no IVS circuit board.



I think we have a win win



Bob Weis

 

[PRout]

Phil, This OEM APPS smells like the work of a bean counter rather than an engineer.

Mike - agreed.

Keep on rollin' guys, class is in session. . Oo.

 

[mhenon]

I got some news, I've been working on finding Williams products and sorting out the part #s with my supplier to get just the sensor. The web sight with there part#s, it was a little confusing. But i got it narrowed done now! I have one sensor right now that has been the test rig and is going to a buddy on monday. I ordered 5 more last wed. and they should be here in about a week 1/2. I am putting a kit together with instructions so that any one that can read a Digital volt meter can do it. The conversion harness will already be done(soldered, not just crimped) all you will have to do is change sensors, plug it in, and set the ldle voltage using the voltmeter and procedure. I aready have 2 of the 5 sold to local friends, that means i have 3 left for anyone that is interested. Price is going to be around $140. I think thats fair. If anyone is intersested PM me.

Way to go timbo! I'm still amazed one of the aftermarket boy's didn't sniff this out years ago. Did you try the Williams APPS in your rig yet? Let us know how that goes.

I'm still waiting on some Deutsch 6 pin connectors to make up a few cables. I can buy the other end, 6 pin Weather Pack's, at the local NAPA. I'll have a few made up as soon as the parts get here. As you said. . a volt meter check for proper idle voltage and it's off to the races.

Mike

 

[mhenon]

... I have been running . 435 on an auto transmission to see how it goes. I think I am running at the low end of the voltage range. Runs fine though. I think I am going to raise mine to . 500 for the long run though. .

Bob, When I was playing with idle voltage the other day the IVS wouldn't trip to accelerate until the wiper voltage hit . 675v. You might manually move the bellcrank with the engine running and see where it trips. It would be interesting to see if your ECM/APPS is doing something different here.

Mike

ps: anyone else with an auto transmission doing the Williams APPS swap

please keep us posted on these voltages

 

[timbo]

Way to go timbo! I'm still amazed one of the aftermarket boy's didn't sniff this out years ago. Did you try the Williams APPS in your rig yet? Let us know how that goes.

I'm still waiting on some Deutsch 6 pin connectors to make up a few cables. I can buy the other end, 6 pin Weather Pack's, at the local NAPA. I'll have a few made up as soon as the parts get here. As you said. . a volt meter check for proper idle voltage and it's off to the races.

Mike

It works on my 5sp just fine! Monday i will be putting it on my buddys auto and drive it around town just to make sure all is well!! Then i will be sending a "KIT" to Brad Patterson ( the man how donated the APPS bracket) to make sure the directions i include are easy to understand and follow!I will then get his feedback to see if the procedure goes smoothly. NOTE I will NOT release any sensors that have not been bench tested and also tested on my truck.

 

[rweis]

I think my trip was ~. 68 volts to accelerate as well.



I am going to adjust the idle tomorrow from . 435 volts to . 500 volts and will take a reading on accelerate voltage. I think what I have is a longer pedal travel (ie delay in pedal linkage) until I hit . 68 to accelerate. It has been running fine at . 435 volts. The auto transmission shifts are the same and it is perfectly normal so far.



My dc APPS was set at . 60 the sticker was . 579



I do want to keep an eye on manual vs auto transmission's to see if there are differences in voltages or amount of travel.



I'm measureing MS bracket options tonight.



IF someone is in their APPS bracket would you measure the amount of offset the idle adjustment screw is holding the bell crank away from the idle adjustment frame member. I have an APPS bracket Gary sent me and it is ~ 1/8". I messed around with the APPS idle set screw so much on the one I am running in the truck I need to know where the "norm " is so I can go from a known point.



Bob Weis

 

[timbo]

That is EXACTELY what we need. A way to make them available, reasonably, as plug and play as possible.



GOOD JOB timbo.



What voltage are you telling them to set it to? I have been running . 435 on an auto transmission to see how it goes. I think I am running at the low end of the voltage range. Runs fine though. I think I am going to raise mine to . 500 for the long run though.



I think we probably need to start a new thread called "How to fix your APPS YOURSELF" so someone does not think a 4 year old post does not have valid information in it. Also does not have to wade through the experimentation. It would be fairly descriptive and to the point as well.



There is still some experimentation going on, so be sure to tell them to check this thread. I think the final best solution is going to be the bus APPS and a MS for the IVS. I am going to start working with a fab shop to design and build the MS bracket just to get the IVS out of the circuitry board stage and into a mechanical stage.



A mechanical MS would also tell them if the APPS pot was acting up because it would be a seperate switch. ie APPS failing, NO DOUBT BUT TO CHANGE THE APPS, because it is the ONLY part in that circuit. It removes the question "is it the APPS pot or the IVS circuit?" because there is no IVS circuit board.



I think we have a win win



Bob Weis

I was going to do the APS and the microswitch method with one of the williams sensors that does not have the IVS circiut in it but i believe some people that do not have a good understanding on electronics, may be a little skeptical about the MS approach. By using the bus APPS it utilizes a sensor that all it needs is an adapter harness and plug it in. I could be wrong here but i think some guys are looking for a "kit" to buy for a reasonable price. I think that some guys are little scared about playing with electronics. BUT there are definitly guys on here that would do it themselves and there is enough info in thread at this point to build your own! Bob, don't get me wrong I personally LIKE the MS approach i just don't think everyone will.

Bob in answer to your ? i set the idle voltage at . 63 and IVS trips at . 67.

 

[Gary - K7GLD]

I was going to do the APS and the microswitch method with one of the williams sensors that does not have the IVS circiut in it but i believe some people that do not have a good understanding on electronics, may be a little skeptical about the MS approach. By using the bus APPS it utilizes a sensor that all it needs is an adapter harness and plug it in. I could be wrong here but i think some guys are looking for a "kit" to buy for a reasonable price. I think that some guys are little scared about playing with electronics. BUT there are definitly guys on here that would do it themselves and there is enough info in thread at this point to build your own! Bob, don't get me wrong I personally LIKE the MS approach i just don't think everyone will.

Bob in answer to your ? i set the idle voltage at . 63 and IVS trips at . 67.

I think you are absolutely correct!



The BEST APPS approach is the one that is most economical and easily duplicated, along with being AT LEAST as reliable as what it replaces. Good solutions - even the cheap ones - are worthless if they are outside the reach and understanding of most potential users.



I'll continue with my own personal effort, that abandons the DC APPS built-in electronics IVS in favor of the outboard micro switch - for the more adventurous guys looking for more hands-on and greater $$$ saving - but YOUR setup is the one far more likely to be successful and duplicated.



Good luck!

 

[rweis]

Totally agree!



Majority will want plug and play and the easiest understood.



Some will want the MS which might be more durable and is more purely mechanical.



At any rate the more of either packages we get out into the CTD population the better and will prove universality. I was thinking the other day, which generations does this apply to? 1st gens?, 2nd gens for sure, 3rd gens?



What is the "audience" of potential users?



timbo, thanks for the info on the idle voltage. I think that as soon as the IVS says "we are in throttle mode" the next event is the ECM asking the IVS the question "are we in throttle mode?" at . 675. That is why my idle voltage at . 435 works. My IVS says "we are in throttle mode" at about . 500. Then the ECM queries the IVS "are we in throttle mode?" at . 675. As long as you drop below ECM throttle validation querie voltage at idle I think you are fine.



Bob Weis