Engine/Transmission (1998.5 - 2002) Cheap High Idle, Oem Feature?

[Texas Diesel]

No Joy :{



Found the PTO lead and took it to +12VDC, nothing.

 

[Gizmo 007]

Ok, to clear up a few things.



Michael, GREAT PIC man!! That's exactly where it is. Split the loom and it should be an orange wire with a white tag that says PTO.



Texas Diesel, your PTO feature is either disabled, or is set to idle speed. You will need to go to a dealership and get them to enable the PTO function and set it to the preset RPM that you want (850 - 2500 RPMs). The tech here in Beaumont stated that only certain trucks come with the PTO feature enabled. Don't worry, it's there.



In depth details... Ok, anytime you want to run a PTO driven attachment (ie. air compressor, hydraulic pump, etc) The attachment usually runs about 1500 RPMs. Our trucks are designed to utilize PTO attachments, and have a built in feature to accomodate a steady speed, high idle. Until now, no one realized (or wanted to figure out) that we had this feature.



I suppose it's best to get the computer set at the dealership. Make sure the PTO feature is enabled, and have it preset to your engine speed preference. Then put a toggle switch in-line that will supply a fused +12VDC power supply to the orange PTO wire. Flip the switch and you now have high idle .



Good luck guys! Ok Max, any more wires you need to figure out?

 

[jboehm]

Giz, Is your's an auto, or a manual transmission? Might make a slight(?) difference in the way the rest of us are wanting to hook this up.



Also had a question regarding the voltage. . if that wire is already +5... adding 12 volts is going to confuse somthing!!!!!!. I can understand if there is zero voltage, and then adding 12. . but . . don't think we have the whole solution yet. There's more too than this than has been posted. And that doesn't even consider the "reflash/PTO boost" you mentioned earlier.



Just still wondering, why, why, it can't be done through the cruise control, like the big trucks. with auto trannys... ... ... . ?

 

[Gizmo 007]

Originally posted by jboehm

Just still wondering, why, why, it can't be done through the cruise control, like the big trucks. with auto trannys... ... ... . ?

Just one word... CHRYSLER . They can't make anything that simple.



My truck has a 6 speed manual transmission with a HD transfer case. Mine was set up for PTO operation from the factory. As far as the +5VDC to +12VDC goes, here's all I can tell you:



The computer works off of a regulated +5VDC power source.

Any unterminated signal coming from the computer will show

this reference voltage. When the line voltage is increased to

+12VDC, the computer senses that the PTO has been

engaged. The computer only works off of +5VDC voltage. It

accepts +12VDC inputs.



Being that I have a little background in small electronics / computers, this makes sense, although it IS unusual to mix voltages. All the +12VDC signal does is to send the computer a message saying "give it some throttle". Kinda like my right foot .

 

[A Johnson]

Here is my understanding of the 5VDC. It has been descibed to me as a floating voltage, yes it is there but it is there to tell the ECM that the switch is off. On most Cummins engines this switch would go to ground, the voltage would drop to zero, and the ECM would then know that the switch was turned on. I can only assume that Dodge requested some sort of reverse logic for some reason. Not trying to really reinvent anything here, if the 12VDC thing works then I must say good job! My . 02 - A Johnson

 

[FAllen]

FWIW



Shop manual for 99 shows PTO sense switch goes to pin 26 of the ECM and connector C125, wire colour = orange (no stripe). Doesn't differentiate between manual or auto, should be there on all according to wiring diagram.



Fred

 

[Amianthus]

More questions.

I'm going to be going into my dealer to get my PCM reflashed to accomodate larger tires. It'd be nice to have this feature taken care of along with TSB 18-019-01. What menu and submenu did the tech at the dealership use to enable this feature and modify it? Any information you can give me on this would be great. As great as my dealer is, they aren't super hot on the diesel.



Thanks.

 

[thepitts]

PTO by Cummins

According to the Cummins web site you can have up to 5 speeds for the PTO operated by one switch.



"Toggle the ON/OFF switch to ON. The engine will assume Remote PTO Speed Setting 1. If setting 2 is desired, toggle the switch to the ON position two times. If setting 3 is desired, toggle the switch 3 times, etc... To operate properly, each successive toggle must take place within . 5 seconds. "



Sounds good to me, one other item would be to put a small 12vdc light that comes on with switch or a lighted switch. Just as a reminder

 

[jboehm]

Got it<G> at least the gist of the last several posts. . NOW... ... . the question is. . is this something the average Joe is going to walk into the dealer and say "need to turn the PTO idle up" without a question from the service manager?



Don't know my service manager hardly, since I've only had the truck in the dealership a couple of times in the past 4 years, (and that was minor warranty/recall stuff) nothing like actually working on the engine. And it appears you need their tech to to it. . Obviously it's gonna cost a few bucks, unless you really know the technician, and have access to their diagnostic computer.

 

[Mad Max]

G1 GIZ!!!!!

Here's a cummins explanation, I do not know if the Ram 50 pin set up has all these options in the menu or not, but it has enough to do this.



http://www.powerspec.cummins.com/site/v5/book/genhelp/isb_pto.htm



Here are my thoughts on programing, again, assuming the Dodge ECM presents all the options that the 100 pin Cummins unit does.



PTO=enabled

PTO Max Vehicle Speed = 0mph

PTO Max Engine Speed = 1,500rpms

PTO MIN Engine Speed = 1,300rpms

PTO Set Switch Engine Speed = 1,300rpms

PTO Resume Swith Engine Speed = 1,300rpms

PTO Additional Engine Speed Switch = N/A

PTO Accelerator Override = Enabled

PTO Accelerator Override Maximun Engine Speed = 1,500 RPMS

PTO Service Brake Override = Enabled

PTO Clutch Override = Enabled (if applicable to one's gearbox)

PTO Maxium Engine Load = 500 ftlbs

PTO Engine Speed Switch Ramp Rate = 100RPMS



I've got a slick 12v lighted rocker switch from Radio Shack just raring to go!



This Rocks!



MaX

 

[Mad Max]

Name For the Mod?

Well, the "Mystery Switch" has been used.



Max Idle Mod?



High Idle Gizmo?



The Rob Thomas is not nuts switch?



MaX

 

[MarkF]

!!!!

Been followin this one closely. I just read most of the Dodge spec link posted above.



Looks like in PTO mode ie. below programmed speed, the cruise control buttons should operate the PTO feature and allow you to select two different speeds. They mentioned the addition of an OEM supplied switch for the third speed selection.



Sounds like the Radio Shack switch may not be needed to make this work. The Shack switch hooked to the PTO wire may be the "third speed" option.



Hate to slow down the wheels of progress but a little more research may perfect this. Just dont let them parts changers reflash the whole darned thing!!!!



Just my . 02 and I want change!!!

 

[Mad Max]

I don't think our cruise controls are set up that way described in the cummins literature.



http://www.powerspec.cummins.com/site/v5/book/genhelp/isb_cc.htm



If you used the cruise control, which only arms at vehicle speeds greater than 30/35mph? how would you deliver a positive current to the PTO lead? The PTO switch sense lead is not connected to the cruise circut in its as delivered state.



MaX

 

[jberelson]

I found the ORANGE PTO wire in wiring harness today. My truck was at the dealer for the breather TSB... My buddy is the service manager there... I told him about the PTO thread, he said we could hook up the DRB when I came to get the truck.



We looked through EVERY DRB menu and could not find anything that remotely looks like a PTO speed setup... (did enable the cold/3cyl flash though) He would like to know where it is also...



Josh

 

[SnoKing]

Just went down and tried this on my 2001. 5, no joy. I did find the wire without a problem. SNOKING

 

[Goddard]

so this wire is for the remote pto control. now does our dodge have the set-up for the regular in cab pto control which uses the cruise control buttons for operation. ??? this is like a cliff hanger

 

[Mad Max]

Remote PTO?

Wire is the only mention of PTO in the entire manual. Also keep in mind, it wasn't until 2001 that "ELECTRONIC CRUISE CONTROL" showed up in our trucks (for the manual trannys only) as I recall from the literature.



I suspect we have limited functionality as compared to the cummins ECM's.



The wire is located under the hood because that is where the ECM (its source) is. It terminates at one of the harness junctures that I suspect takes some wires into the vehicle eventually, our PTO lead just isn't one of them, so we get to run a few more wires through that gromet in the fire wall.



Hopefuly I'll get to sit down with the dealer's tech and browse the menu's with him. Then we'll know just how similar our ECM is to the Cummins set up w/ respect to PTO programing and features.



MaX

 

[moon]

PTO?

This sounds good but will it be strickly for a standard transmission or will the auto have the wires and the feature?

 

[zstroken]

ECM Uses Solid State Devices

Yep you are correct on the 5v probablybeing a float. If you gusy saw a schematic of the input circuit I am sure it would make more sense. I imagine the ECM uses a tansistor type switch(IGBT,FET, or such) Which as a leakage current of such or they tie one end on the lead. Anyway if you wonder if the 5 volts is really there try hooking up a simpson, if it is a floating voltage the simpsons internal resistance will pull it down, using a DMM on them they have such high input resistance that it will not pull a floating source down.



I plan on hooking up a thermostat, and a microswitch to the parking brake. If it is below the setpoint of the thermo and I shove the parking brake on Presto High Idle. I might even put in a timer to delay the high idle for 60 seconds or so, hence on the cold morning I can fire up the diesel shove on the parking break, let it idle for 15 seconds or slow at lower speed to get the oil moving then timer times out and boom high idle. I already have found the thermostat, switch is a piece of cake, just to find the 12v timer.

 

[thepitts]

Gizmo 007

This is from his post

"Mine only ramped up to 950 RPMS when I applied 12 volts. I had it reset today at the dealership to 1250 RPMs. WooHoo, now we have something!"



Maybe he can tell us where it is on the DRB menu. Can you help us?