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Cruise disengagement

Not thinking today and managed to have retarder engaged whilst cruise control was on . Now with retarder disengaged joy stick forward, the cruise works fine going uphill or on flats but disengages every downhill , anyone had this before
Jimmy
2003 U295 3620

Re: Cruise disengagement

Reply #1 –
Quote from: Jimmyjnr –
Not thinking today and managed to have retarder engaged whilst cruise control was on . Now with retarder disengaged joy stick forward, the cruise works fine going uphill or on flats but disengages every downhill , anyone had this before

With retarder joystick pulled back (any position but all the way forward)  and master retarder on, as soon as throttle goes to zero, retarder engages and shuts down the cruise control.

With joystick all the way forward (but master retarder on), cruise does not shut down on our coach with zero throttle (unless on the brake pedal).

Perhaps some "grunge_ has your coach thinking the joystick is pulled back one position?
Dan - Full timing since 2009
2003 U320 40' Tag 2 slide

Re: Cruise disengagement

Reply #2 –
Jimmy, turn on the retarder with the joy stick all the way forward, like Dan said.

Re: Cruise disengagement

Reply #3 –
Master switch is on , joy stick forward ( off) cruise works on flat and uphill but dis engages on downhill
Jimmy
2003 U295 3620

Re: Cruise disengagement

Reply #4 –
Quote from: Jimmyjnr –
Master switch is on , joy stick forward ( off) cruise works on flat and uphill but dis engages on downhill

The coach (Allison) "thinks" the joy stick is not all the way forward is my best guess.  Grunge, corrosion, connectors, etc?

Also possible coach thinks the brake is on?  Check with coach running and see if brake lights are on without touching the brake pedal.
Dan - Full timing since 2009
2003 U320 40' Tag 2 slide

Re: Cruise disengagement

Reply #5 –
Jimmy,

I'm not sure where your retarder interlock sending units (you may have as many as 3)  are located on an '03 but it sounds like one is stuck/bad.

The part numbers that I have are for the 4060R and I don't know if that will cross to your trans.
Mike
Pamela & Mike 97 U 320

"It's not what happens to you, but how you react to it that matters."

Re: Cruise disengagement

Reply #6 –
Does retard indicator light work? If not get it working.

If light comes on with downhill, retard is not off.

When retard comes on, it turns on brake light. When brake light comes on cruise will turn off. It is the brake light that kills cruise, not retard. Brake light comes on with foot brake pedal or retard active. Some can choose to disconnect the brake light with retard with a switch, so cruise will not disengage and when downhill is at bottom, cruise will re-engage throttle on the uphill.

Re: Cruise disengagement

Reply #7 –
Just had call back from Foretravel and James confirmed everything you guys are saying, cruise thinks retarder is engaged.
His advice is go to a Cummings dealer and have them plug it in for diagnostics.
Just left coach at Temecula valley Rv for a bladder so this problem is weekend task
Jimmy
2003 U295 3620

Re: Cruise disengagement

Reply #8 –
More useable after the repair to alter the system to have the retarder work with the cruise control.  That seems to disconnect the brake light coming on when the retarder works. 

I thought our brake light still works with the cruise and retarder but a post here says that the brake light coming on kicks off the retarder.

Not suggesting that anyone do  anything unsafe so this is just a option.

But I would not reconnect mine to the original way

Different drive to have the retarder work on cruise control.

If you want some overrun down a grade just return the wand to the off position. 

M11 remembers the last speed set which is handy regardless of if you turn the cruise off with the brake or the power on the steering wheel
"Riding and rejoicing"
Bob
1997 U320 40' Mid entry, build 5132,  wtbi ce27, 4th owner
2007 Solara convertible
2 prodeco tech outlaw ss electric bikes

1095 watts solar
08 Ls 460 and a sc430
2000 Ford F-250 superduty 4x4

Re: Cruise disengagement

Reply #9 –
Our brake lights do not come on with retard active - we checked by wife following coach as I tested it out.  Retard still turns off cruise control when throttle is zero input.
Dan - Full timing since 2009
2003 U320 40' Tag 2 slide

Re: Cruise disengagement

Reply #10 –
All of the above is proof that Foretravel never built two coaches alike
The only time I ever use cruise control is in West Texas/Eastern New Mexico.

Re: Cruise disengagement

Reply #11 –
Quote from: AC7880 –
Our brake lights do not come on with retard active -

Dan,

That sounds like the relay that controls the brake lights that is fed from the retarder sending unit has failed.

Mike
Pamela & Mike 97 U 320

"It's not what happens to you, but how you react to it that matters."

Re: Cruise disengagement

Reply #12 –
Quote from: Pamela & Mike –
Dan,

That sounds like the relay that controls the brake lights that is fed from the retarder sending unit has failed.

Mike


I prefer no brake lights with retarder use.  When coming down a mountain with retard on, if something happens ahead and I get on the brakes hard, I want the brake lights to come on at that point to warn drivers behind me. If brake lights are already on due to retarder use, and I nail the brakes hard with a tailgater, more likely to get tail ended.

Everyone's personal preference, but I want brake lights only with active braking.
Dan - Full timing since 2009
2003 U320 40' Tag 2 slide

Re: Cruise disengagement

Reply #13 –
Be fun to do like 7 series BMW's do which is to have proportional brake lights depending on how hard you are on the brakes. 
"Riding and rejoicing"
Bob
1997 U320 40' Mid entry, build 5132,  wtbi ce27, 4th owner
2007 Solara convertible
2 prodeco tech outlaw ss electric bikes

1095 watts solar
08 Ls 460 and a sc430
2000 Ford F-250 superduty 4x4

Re: Cruise disengagement

Reply #14 –
We put a new switch on dash to allow retard to turn on brake lights.

But mostly leave switch off, so when driving Interstate with retard joy stick pulled back a little, a slight downhill will speed up coach bringing throttle to idle with a little retard (without brake lights).

When at bottom of grade, coach speed drops forcing cruise control to increase throttle.

If we drive the same way with dash switch on, the first down hill brings throttle to zero position, allowing retarder to activate, turning on brake lights and instantly killing cruise control until manually reactivated. So at bottom of grade, coach will not throttle back up.

When driving with joy stick not in off position, retard only works when throttle is in zero / idle position.  Pressing on throttle, turns retard off, even with joy stick back.