Question aobut DDEC 1 Cruise Control Wiring

NJT5047 · September 03, 2006, 06:45:13 PM

Anyone completed the wiring on a DDEC 1 unit cruise control? I have the wiring diagram from both NJT and DD DDEC 1 troubleshooting guide and they don't agree. The NJT man indicates a double throw, double pole on-off switch. THe NJT manual also indicates two lights for cruise...one is an "enable" and the other is "cruise on"...what the H is an "enable" light for? I've managed to pull all of the required wires from the harness. They appear to be connected to the ECM per plan. But, the DDEC manual indicates what would be a dead short (in my opinion) with wire 150 and the brake light switch (M2 ground in J1A). The DDEC 1 man shows wire 150 going to the "on-off" switch, but connecting wire 558 when the switch is on, and wire 531 when the brakes are applied. Perhaps the system is always hot and the on-off completes the circuit to ground? Because these wires terminate in the ECM, I have no idea what sort of signal to look for...I can figure it out...eventually, but maybe someone has done this before?

Will I have to change the brake light switch? The diagram indicates it makes a circuit in both "brake off" and "brake on"..? The ECM already "sees" the brake light circuit as the retarder is connected to the brake light circuit.
Another major issue is the lack of ignition controlled wire 439 in the DDEC man. The DDEC manual may be using wire 439 for the "cruse enable light" but they don't ID it as such. DDEC only shows one light...while the NJT manual shows two lights and a 24VDC feed for the "cruise on"...?? Maybe the DDEC man uses an "always on" system, and the NJT man has an "on-off" control switch. The NJT "cruise on" light is wired to a 24V ignition source. The DDEC man doesn't indicate what the "enable switch" is connected to...24 or 12V. I wouldn't care if the cruise was on all the time.
NJTs have the cruise enabled. I want to hook it up...preferably without smoking (letting the smoke out) the ECM.
The variations between the two schematics are remarkable. The NJT manual is about impossible to read due to the scale. However, the switches are easy enough to see. The DDEC is pretty simple looking...the NJT is a good bit more complicated. Maybe both will work?
Another question...if you're still with me...the resume and set switches appear to be momentary with a completed (closed circuit) in the off position. Do they always switch back to the off position? Do the set and resume switches in fact make a circuit in both the off position and momentary "on" position? I gotta buy some switches and don't know exactly what I need. I'm not familiar with momentarys that make a crircuit in both positions...obviously, they exist.
Those of you'ns that have NJT DDEC 1s, there is a tach lead (505) and 5 unused wires (700's) in the harness. Easy to access these items. There is also alternator tach lead in the junction boxes on MC9s.
BTW, someone recently said that a 24 to 12DC power supply was in the pedestal that I removed from the bus...found it. Looks like a useable item for my radio...I'm tired of having to remember to turn it off. I know...could have used a relay...but, I believe I've got a 24V solution! Thanks to whomever ID'ed this thing. I had no idea that it was in there.
Reckon I'll get the magnifying thingy out and see if I can further make out some of the NJT wiring.

Thanks for any ideas on this item, JR

NJT5047 · September 04, 2006, 07:23:29 AM

Now I"m replying to my own posts...

After sitting here for a few this morning and llooking at the schematics, I see that the two systems are the same, with the NJTs having an On-Off light. Has no effect on the system op. And both the NJT and DDEC OEM cruise can be turned off...they just do it differently. I suppose the "enable" light just indicates that the system is on and functional. It's just a ground thru the ECM.
Now all I'm looking for is the "set" and "resume" switches, and the brake switch. The brake switch works as does the set and resume switches. It makes a circuit in the "off" and "on" position. The ECM wants to know what position the switches are in...They are all wired in a sort of series system. I don't know what DD used for a brake switch...an elaborate air op switch, or a relay from the two lead brake light switch.
Much clearer this morning!

If anyone can suggest where these oddball switches could be located it would help. The brake switch could be accomplished with a relay.
Thanks, JR

DrivingMissLazy · September 04, 2006, 10:31:07 AM

JR, I suspect they are a very standard switch that is typically called double throw. They would typically be abbreviated in a parts catalog as SPDT for single pole, or DPDT for double pole switches. They can be one single pole or multiple poles. For example, you could connect ground to the center swinging contact. Then in the up position it would connect one circuit to ground and in the down position it would dis-connect the up position contact and then connect the lower position contact to ground. They are available in a two position switch with just on-on, or in a three position with on-off-on. These are also available in rotary action switches if desired and a further selection would be either make-before-break, or break-before-make.
Richard

Quote from: NJT5047 on September 04, 2006, 07:23:29 AM
Now I"m replying to my own posts...
After sitting here for a few this morning and llooking at the schematics, I see that the two systems are the same, with the NJTs having an On-Off light. Has no effect on the system op. And both the NJT and DDEC OEM cruise can be turned off...they just do it differently. I suppose the "enable" light just indicates that the system is on and functional. It's just a ground thru the ECM.
Now all I'm looking for is the "set" and "resume" switches, and the brake switch. The brake switch works as does the set and resume switches. It makes a circuit in the "off" and "on" position. The ECM wants to know what position the switches are in...They are all wired in a sort of series system. I don't know what DD used for a brake switch...an elaborate air op switch, or a relay from the two lead brake light switch.
Much clearer this morning!
If anyone can suggest where these oddball switches could be located it would help. The brake switch could be accomplished with a relay.
Thanks, JR

JackConrad · September 04, 2006, 03:07:37 PM

Switches are as Richard described with one addition. These switches are also available as momentary contact. A momentary contact, double pole, double throw, center off switch would be shown as DPDT (on)-off-(on) This is what you would probably need for the Set/Deccel. and Resume/Accel. switches. Jack

DrivingMissLazy · September 04, 2006, 05:43:48 PM

Jack, I think for momentary contact you would have to add MC to the description. Therefore DPDT-MC would be the appropriate designation for momentary contact.

It is also possible to get them that are momentary contact in one position and maintained contact in the other position as well as off position.

What you describe is a three position switch with the switch maintaining contact in either of the on positions, as selected, and no contact in the center off position.

There are literally dozens of combinations available, so be sure you know what you want and understand exactly what you are ordering.
Richard

Quote from: JackConrad on September 04, 2006, 03:07:37 PM
Switches are as Richard described with one addition. These switches are also available as momentary contact. A momentary contact, double pole, double throw, center off switch would be shown as DPDT (on)-off-(on) This is what you would probably need for the Set/Deccel. and Resume/Accel. switches. Jack

NJT5047 · September 04, 2006, 07:38:39 PM

About all I know about the switches is that they are 3 terminal, two position, with ON-ON. They make contact in both positions (switching circuits between the terminals). They likely are Break-before-Make. But they are momentary. They all default to the "off" position...although this is what the ECM must see to "enable" the cruise control.
They maintain a brake off, set off, resume off, circuit that must close before the enable light will illuminate.
In what would typically be the "off" position, the switch makes a circuit thru one of the lugs...and it switches to the other lug when moved to the other position. I'm not making this easier. I know what I'm looking for, but I'm doing a lousy job of explaining it!
I'll call Luke this week and see if maybe he has a panel or something such as a takeout...or new. Be a small panel with 3 switches. The cruise on=off can be a simple SPST...or is that STSP. But the set and resume switches are oddities. I've not been able to think of anything that uses a switch like this...may get out the Grainger book and see what they have.
I need to find a relay for the brakes that makes contact in both on and off positions too. That is easy...Probably something in that AC system I removed?
Thanks for the help...I'll post the end result...not many people around with 87 DDEC 1 electronics that want to use the DD cruise control....I may find out why soon.
JR

NJT5047 · September 06, 2006, 11:03:38 AM

OK Jerry and Richard and Cliff and anyone else that wants to jump right in here...ya'll are electrical gurus...what about using 3 Bosch style 5 pin relays for the switches to control the cruise control? Just two push button "set" and "resume" switchs...that solves the SPDT switching (I cannot find any SPDT-MOM switches) and use the 3rd relay for the brake circuit that must also indicate "OFF" thru a circuit. The Bosch 5 pin relays have both NO and NC pins that alternate when "On" and "Off." Relays would also solve the "break before make" problem.
I can find plenty of DPDT On-Off switches to use for the main control switch which would give an "ON" light on the cruise circuit and the other side of the switch could control the cruise "On-Off" function.
Will these small Bosch relays handle continuous duty?
Since the DDEC is 12V, I'll use the 439 wire for ignition hot. 439 is in a small junction box beneath the drivers seat...in the spare tire compartment.
Thanks for any consideration and recommendations! JR

JackConrad · September 07, 2006, 05:49:12 AM

(I cannot find any SPDT-MOM switches)
www.waytekwire.com Part #44258 or www.delcity.net Part # 7000026, 7000023, or 7000029 You could also use a DPDT by only using one side of the switch. Hope this helps, Jack

NJT5047 · September 07, 2006, 09:18:42 AM

Thanks Jack, I looked thru some of Delcity and didn't see any DPST-MOM switches...this would be a two position momentary switch that makes circuits to a common term in both positions. I orderd some Bosch DTDP relays yesterday and should have them AM tomorrow. The design is headed that way. I needed something for the brake circuit anyway. Hope the cruise works?? It would be nice to have!
I'll peruse Waytek in the next few...someone has these things...I can always find a use for the relays if they are not used on the cruise. These are Harley Davidson starter relay upgrades. Got neat little bases and all.
Thanks again, JR

Dallas · September 07, 2006, 11:16:42 AM

Quote from: NJT5047 on September 07, 2006, 09:18:42 AM
Thanks Jack, I looked thru some of Delcity and didn't see any DPST-MOM switches...this would be a two position momentary switch that makes circuits to a common term in both positions. I orderd some Bosch DTDP relays yesterday and should have them AM tomorrow. The design is headed that way. I needed something for the brake circuit anyway. Hope the cruise works?? It would be nice to have!
I'll peruse Waytek in the next few...someone has these things...I can always find a use for the relays if they are not used on the cruise. These are Harley Davidson starter relay upgrades. Got neat little bases and all.
Thanks again, JR

Hey, JR!

Is this what your looking for?

It's DPDT MOM
If you want it send me an address and I'll put it in the mail for you.

Dallas

NJT5047 · September 07, 2006, 12:09:54 PM

Thanks Dallas..did you get the Timmonsville gig posted on the MCI, BNO, and NJT boards?
Regarding the switch...close..but that ain't quite it. Need a switch that has two positions, 3 terminals, and makes a circuit in both directions...but switches between the circuits...that's clear as mud isn't it! AND add to the needs, it is momentary. STDP-MOM?? It's crap like this that keeps poor folk from finishing these conversions. Spend too much time on simple things.

I wouldn'ta thunk that a switch like this would be difficult to find...but it is. I've got it covered now. I believe. I'll bring the results down Timmonsville...one way or another! The cruise has not been an item of interest up till now...but I was looking for air leaks the other day....and there was the big wire coming off the DDEC. I've looked at the cruise circuit so much that I had the wire codes memorized...so I had a look. The wires were all there, and they are patent to the ECM. What the hey! Need to try this before Arcadia. That's a long way to pedal a bus. Reckon it's about 650 miles from me. I could use a non-MOM switch like you picture for the ON-OFF control...a STDP." One side would control the ON-OFF light and the other side would control the cruise ON-OFF.
You know I have been unable to locate any air leaks...must be the wipers or wiper controls. I'm going to get an electrical wiper motor conversion for this thing. I really don't like the air motors. I know they're good long lasting items...but mine is just crude. The left wiper parks way too hard. That's the new air motor. All things in good time.
Cheers, JR

Dallas · September 07, 2006, 02:12:23 PM

Quote from: NJT5047 on September 07, 2006, 12:09:54 PM
Thanks Dallas..did you get the Timmonsville gig posted on the MCI, BNO, and NJT boards?
Regarding the switch...close..but that ain't quite it. Need a switch that has two positions, 3 terminals, and makes a circuit in both directions...but switches between the circuits...that's clear as mud isn't it! AND add to the needs, it is momentary. STDP-MOM?? It's crap like this that keeps poor folk from finishing these conversions. Spend too much time on simple things.
I wouldn'ta thunk that a switch like this would be difficult to find...but it is. I've got it covered now. I believe. I'll bring the results down Timmonsville...one way or another! The cruise has not been an item of interest up till now...but I was looking for air leaks the other day....and there was the big wire coming off the DDEC. I've looked at the cruise circuit so much that I had the wire codes memorized...so I had a look. The wires were all there, and they are patent to the ECM. What the hey! Need to try this before Arcadia. That's a long way to pedal a bus. Reckon it's about 650 miles from me. I could use a non-MOM switch like you picture for the ON-OFF control...a STDP." One side would control the ON-OFF light and the other side would control the cruise ON-OFF.
You know I have been unable to locate any air leaks...must be the wipers or wiper controls. I'm going to get an electrical wiper motor conversion for this thing. I really don't like the air motors. I know they're good long lasting items...but mine is just crude. The left wiper parks way too hard. That's the new air motor. All things in good time.
Cheers, JR

JR..

That is an M-O-M switch. It has two poles on one end, two poles in the middle and two poles on the other end. If you look at the picture, it shows the switch in the middle position if you pust it either way it goes back to the center.

Oh, and I got kicked off the MCI board years ago, and I don't belong to the NJT board. I'll post to BNO tonight.

NJT5047 · September 07, 2006, 06:30:20 PM

You park the Timmonsville info and I'll post it on the NJT and MCI groups. I got another guy that wants to come down for the festivities. He's a good, but quiet musician too...but not a big parking lot picker. He camps in a "teardrop" camper. He goes to most of the music festivals. He has a 36' S&S, but like to camp in the tiny toy. You still have some 15A outlets?? I sent the registration to him.
Regarding that switch you have. I'll send you a pix of what I need (I got it covered now). I see what you have there...but, the switch that I need must make a circuit when released also...it would not have an "off" position...just two "on" positions. It would switch back and forth to one or the other circuits. The MOM circuit would be the actual "set" and the circuit when not being activated would be a verified ECM ground which "proves" and off position. If you saw the schematic, you'd see what I cannot put into words!
Here's a stab....picture a momentary 2 position switch with 3 terminals...T-A, T-B, and T-C. When the switch is released terms A and B make a circuit. When the switch is depressed, terms A and C. Make a circuit. Terms B and C never communicate. Only A to B or A to C. The ECM has to see a positive Off (to ground) or a circuit to the "set" ECM term...one or the other. This is done on the brake circuit, the "set" circuit, and the "resume" circuit. I had to find some way to make the brake switch do the positive off and on..so I bought a DA relay. Then saw the light and bought several more. They solve the problem.
Onward and Upward! JR