Jakes and Cruise quite working -- solved

[rv_safetyman]

Well, the village idiot got the problem solved.  See my post down the thread.

Jim

>>>>original post>>>>>

Of course we are on the road without the manuals . 

Engine is a Series 60 DDEC IV. 

Put the Pro-Link on and the cruise switches (J1, G3, and F2) all function correctly.  The Jake switches (K2 and K3) also function properly.

I suspect that I have an issue with the clutch, service brake or park brake switches.  The only one the is hooked up "properly" is the service brake and the G2 switch is gnd when the brakes are not applied and opn when applied.  The park brake switch is one I wired with a switch so that I could get high idle and the pro-link shows it working correctly.  The strange thing is that the high idle works just fine (guess that confirms the park brake switch and the cruise switches function properly)

That leaves the clutch switch (J2) and it shows opn (switch not hooked up to the clutch).  Not sure that it should be opn.

Any thoughts from the experts?

The jakes and cruise failed shortly after I started driving today (491 miles and one pretty good pass without jakes) not a lot of fun.  When they don't work, you really understand how wonderful they make the driving experience.

I think the problem began when I rested my foot on the clutch master cylinder which is down it the wiring "rat nest" and I probably pulled a wire, but I sure can't find it.

Thanks for any help.

Jim

[HB of CJ]

Continunity issue?  Yeah, pulled wire, but where?  Do you remember hitting or running over any road debris?  Pedal area or rear end?  How much spare wire do you carry?

[lostagain]

I had the same thing happen last year on the 102D3, S60, 7 speed Eaton. One of two return springs on the clutch linkage at the bell housing was broken, so the clutch pedal wasn't returning all the way back up, not closing the Jakes switch at the pedal. Simple fix once I figured it out.

Hope this helps.

JC

[rv_safetyman]

Thanks for the quick replies.

HB, I carry plenty of wire, but I really suspect that this is a DDEC issue where one of the switches is not set properly, so it thinks that there is a condition where it will not allow them to work.  For example, it might think the  clutch is pressed or something like that.

CJ, your comment kind of confirmed that the primary suspect is the clutch switch.  I am just not sure whether it should be in the grounded or open position.

Would love other thoughts if folks have them.

Jim

[Brian Diehl]

Jim, My Cummins wants it in the "closed" position.  On the Cummins everything is essentially grounded when "on".  At this point you don't have anything to loose.  Do you have the DDEC wiring diagram?  If so, consult that to determine where the wire should go.  BTW, All my grounds are home run back to the engine where one massive ground to chassis is used.

[rv_safetyman]

Hi Brian.  I do not have the full schematic with me. 

I think I will try to ground the clutch circuit like you suggest.  It seems to most obvious thing.  What troubles me is that I don't see any place that I made the connection in the original installation, and it was working fine up until yesterday.

The DDEC system uses the same process: switch goes to ground to turn on circuit.  It also has it's own specific ground tied into the computer.

Jim

[RTS/Daytona]

sent you an email - of the DDEC-II (same pin #s for cruise control)

will try to post here too

[Don4107]

I would watch the clutch indication from the DDEC, if possible, while you have someone pull up on the clutch and then push the clutch down.  You should see a change if the switch and wiring are intact.  Or monitor with a meter.

I bet next trip the manuals go with. 

Good luck
Don 4107

[Busted Knuckle]

Hi Jim,
I don't know your system or how ya wired it. But I had several DD 60 Series in my big trucks. And several times I had problems exactly as you are describing. Every time it was a broken wire except once when the switch itself went bad! The switch needs to be closed, so that it can make theconnection until you push in on the clutch! "After all if your pushing the clutch there is no since in the JAKE being on now is there?" LOL! (sorry I couldn't resist as that was what it took to make one of my drivers to understand what I was saying when he was in CA w/no jakes and I was in OK!)

I even once found out by accident that if I double clutched the pedal while shifting the cruise would self resume on one of my trucks. So I had the rest of them programmed to do it also! 
Now to make the correction before someone or anyone who knows me very well gets started! Honestly I never could double clutch! Never could, and to this day still can't! But the truth is I never used the clutch any way except too get it moving from a dead stop in either direction! Once rolling I'd "float the gears" by using the throttle to ease it in and out of gear! But I learned that I could leave my jakes on all the time (except in bad conditions) and just tap the clutch pedal to interupt the cruise while preventing the jakes from coming on while I shifted. Well once I learned about the double clutch resume, I'd double tap the pedal and the cruise would stay right on doing it's job and no jakes either! FWIW HTH   BK 

[Sammy]

JIm, J2 should show "closed" on proLink when clutch pedal is released.
DDEC should "see" a digital input (battery ground) when pedal is released.
J2 circuit should be an Orange/531 wire to clutch switch.
I have a DDECIII/IV Application and Installation manual too if you need more info.
Good luck with your repair.
Sammy

[rv_safetyman]

Well, most of the input has focused on the clutch switch circuit.  I had the same feeling but could not see any wiring issues.

That was the problem, but you will never believe what caused the problem (those of you who know me will not be surprised).

I was working on a deadline to get the bus on the road a couple of years ago and never really got the wiring properly finished (want to use terminal blocks for every wire in both the engine and transmission harnesses).  So, I simply hooked up the wires, made sure everything worked and they tied them all together with tie wraps.

This morning, I cut off all the tie wraps and traced the clutch switch wires.  Well, hidden in the bundle was the actual clutch switch from the truck.  I remembered that I wanted to leave it in place in case I ever wanted to attach it to my crazy clutch linkage.  Bear in mind that is is not a big deal that it is not properly connected to the clutch since the clutch is only used to start and stop and you hit the brakes before you would touch the clutch. 

Anyway, I had TAPED the switch in the close position and the tape finally let loose after a couple of years!!!

Today I got to really enjoy the cruise control and jakes.  Maybe this was mother nature's way of making me appreciate what a great system I have

Thanks for all the great input and help!!!!  What a group!!!!!

Jim

[Brian Diehl]

That is hilarious!      I'm glad to learn it was such a simple solution.  Maybe it is time to put it in place permanently now?  I use my clutch switch to easily disengage the cruise without having to use the brakes.  That way I can put my foot down on the fuel pedal *about* what I think the current fuel demand is and then disengage the cruise control to enable me to seamlessly come off the cuise.  This is especially handy when coming up on traffic or a town where the speed limits drop, but you don't yet need to be on the brakes.

[Busted Knuckle]

Glad to hear it was a simple fix! And that I was right! LOL!   BK