When driving the coach home this weekend, I noticed that when I used my turn signal to pass a vehicle the cruise control would kick off. Never noticed it before, but is this normal?
Larry
No, sounds like it's back feeding, making the cruise think the brake lights are activated. Have checked to lights physically, while someone works the lever and brake pedal?
Chris
Yes. Dirt and crud built up in the switch of smart wheel. Dim/bright or turn would make cruise kick off. Hitting wiper buttons would make cruise kick off. MOT took apart wheel, cleaned contacts and has worked perfectly sense
Larry,
You and Jerry Whiteaker should get together - sounds like your coaches are both being infested by the same electrical gremlins!
TURN SIGNAL CAUSING BRAKE LIGHT TO FLASH (https://www.foreforums.com/index.php?topic=36842)
Larry,
Looks like we have a similar problem. One thing I forgot to mention, when the problem was happening, the engine was also surging a little bit. Most noticable at a low speed in first gear although I could feel it at any speed. I think this is/was due to the King throttle control which is electric not giving a steady pull on the throttle cable. Did you notice that, if you have the King throttle?
Chris, I didn't have the wife watching while I drove. I will this weekend when we bring it home again.
Tim, I don't have the smart wheel. My cruise is on the urn signal stalk like the older GM vehicles.
Jerry, I didn't notice any surge. I was doing 70 down the highway and passed a tractor trailer. Turned on signal to pass and the cruise kicked off. Then happened again when I turned on the signal to exit the highway.
Larry
I would peel back the rubber cover on the turn signal stalk and inspect the cruise switch to begin with.
Strangely enough, yes it is normal. The cruise control sees a brake light, or the electrical version of one, and does its thing. Your 4-way flashers will do the same thing. Noticing this only shows that you're getting comfortable driving your rig.
this is not normal Larry. Cruise shutting down like that would render it useless. If it senses a turn signal the same as a brake light then it's sensing wrong. Unless I'm misunderstanding op.
If you have a converter installed between coach and tow car (the thing that allows for integrated brake/turn signal lights) might try unplugging it and see if it's back feeding somehow.
Ours does the same thing. Yep.. shuts off when turn signal is used. Always has. I just figured it was a built in safety thing. Like maybe I was supposed to have personal control when passing. Or turning a corner. Not to far fetched maybe ??
I could be wrong, I never noticed mine doing it , guess I will back out
My coach has not done that (turn signal kicking off the cruise control) for the 10 yrs that I have owned it. It did it for 2 days recently then went away. It took me a day to figure out what was causing it. Mine may have been due to the electrical tow cable. Any time the brake light comes on it will disengage the cruise control as it is supposed to do. Turn signal should not cause the brake light to flash.
I can understand the brake light signal shutting it off. I will have to chase down if their is a short, bad bulb or just gremlins.
Thanks for the comments, keep em coming
Larry
Jerry, have you checked the bulbs, I have had one filament burn off and drop onto the other filament,all kinds of strange things happen .... Hope you find your problem..
Safe Travels,
Dave
I know ours has done the off thing when turning for a long time but I'm actually betting it's not supposed to.
I guess I'll be investigating that now. Dang it's always something. Good thing we LOVE our coach cause we'll do whatever's needed.
That was one of the first things I checked. Tapped on the bulbs to see if maybe a filament was broken as sometimes they look ok when they are actually broken. Drove coach to storage last night, turn signals and other lights normal.
Well Jerry, Good ideas can be easily discarded!! Hope you find you problem .
Safe Travels
Dave
Brett will hate me after installing a King Control (set to 75%) unit. After 300,000 miles of driving without one, I never use his. Old habits, 'ya know! ^.^d
Nope, no problem.
Except on relatively flat ground, a good driver can do better (particularly from an MPG standpoint) than a cruise. On many small, short grades (like freeway overpasses), a cruise will go to WOT, while a smart driver doesn't do anything.
My opinion these 6 speeds shift down to quick as in slight overpass grade. Even a 300 wouldn't lug in that short of pull. Rev up and suck fuel just like Bret said all to get over a no hill.
Dub,
Use "economy mode" to markedly reduce downshifts on those overpasses.
I don't see that option on my shift pad Bret. Didn't think 96 had it. Hope I'm wrong.
Upper right corner of the Allison shift pad. Labeled "mode".
Default is power mode-- starts there at every restart of the engine. Pushing the mode button puts it in economy mode and the little red light illuminates.
You can switch between the two as often as you like, while stopped or driving- any speed, any time.
Sitting in the bus now and I wanna thank ya. Crap I thought the word mode meant that the transmission was in the gear lit up on the screen. Man I don't know how I get out of the blasted yard let alone make it down the road.
Dub,
You are good. Many have driven these things for many years without having the faintest idea what that button/light do.
If you want a primer on using it, let us know. I know I wrote an article for the FMCA Magazine many years ago on the use of the mode button.
Primer would be good.
Here is a except from the article I wrote back in 2013:
ALLISON TRANSMISSION MODE BUTTON
BY BRETT WOLFE, F252125
The Allison transmission control module (TCM), which is the "electronic brain" that controls shifting and other functions of the transmission, has two different automatic gear-selection modes/programs.
In Economy Mode, the transmission will not downshift even at wide-open throttle until the engine pulls down to peak torque rpm in some applications and 200 rpm lower than Performance Mode in others. In Performance Mode, the transmission will downshift much earlier to maintain higher engine rpm.
Only at higher throttle positions is there any difference, so on flat ground you will not notice any variation between the two modes, except when accelerating from a stop if you are at or close to wide-open throttle.
However, mode selection can make a big difference when traveling over rolling hills. If you drive in such areas while in Performance Mode (particularly with the cruise control on), it is common for the transmission to shift down to fifth gear on the uphill and back to sixth gear on the downhill, repeating this process hundreds of times. In Economy Mode, the transmission will stay in sixth gear unless the hill is so steep or so long that the engine cannot pull it without dropping below peak torque rpm. According to engine manufacturers, the most economical way to climb a hill with a modern turbocharged diesel engine is in a higher gear (lower engine rpm), provided the engine doesn't overheat.
If, while driving in Economy Mode, you know you will need a lower gear because of the steepness of the grade and/or the engine temperature is rising higher than the thermostatically controlled temperature, use the down arrow to drop a gear (this is what I do) or switch out of Economy Mode. Be sure to switch back into Economy Mode when past the steep section or you will be stopping at a service station for fuel sooner than you expected.
While you are driving in hilly terrain, if your engine begins to overheat, the engine's horsepower-to-weight ratio is low, or it irritates you to lose a few mph in the name of saving fuel, by all means drive in Performance Mode.
It confuses me to hear people advocate driving in Economy Mode only on flat ground, as there is not 1 percent difference in shift rpm between Performance and Economy modes on flat ground, except when accelerating from a stop if you use wide-open throttle.
Every time you start the motorhome, the transmission is in Performance Mode. This is the default setting. If you push the mode button, it goes to Economy Mode and the light illuminates.
There is no absolute number that can be given to illustrate the difference in fuel economy that will result when driving in Economy Mode. On flat ground where you will be in sixth gear no matter what mode you are in, there will be zero difference. The most significant difference in mileage will occur in rolling hills, where in Performance Mode, particularly if on cruise control, you will start up a hill in sixth gear, go to wide-open throttle in that gear, and downshift to fifth gear still at wide-open throttle, where it is using a lot more fuel. After the hill is crested, the transmission will upshift to sixth, then likely coast a little in that gear unless you are driving with the exhaust brake on. If you are, the exhaust brake will be applied and the transmission will downshift toward the preselected gear, which is generally either second gear or fourth gear. And so the process will continue, with the transmission shifting up to sixth gear on the downhill, back down to fifth gear on the uphill, etc. The problem with this is that a modern turbocharged diesel engine is much more efficient at low rpm with high throttle settings.
Note: In either mode, you are free to use the up and down arrows to proactively choose the correct gear. You cannot screw anything up, even if you downshift to first gear at 70 mph. The transmission circuitry understands that you want to downshift to the next lower gear as soon as the engine rpm will not exceed the preset amount. Then it will downshift again when safe.
By the same token, you can shift between Performance and Economy modes as often as you want with the transmission in any gear when you make the change.
I drive in Economy Mode 99 percent of the time, including in the mountains. I use the up and down shifting arrows to choose the proper gear. I use Performance Mode only to pass another vehicle on a two-lane road, when I am willing to sacrifice a little fuel economy to gain a short-term burst of speed.
Very informative.. My mpg has been poor and now I think it will improve. Many thanks..
This is the first 6 speed I've had as the 280 had a 4 speed with a shift lever and not many selections. Also had manual leveling that I liked and wish Ft had stayed with but mfg do not stay stuck on just basics that we dinasuars prefer ... there fore the learning curve continues and that isn't necessarily a bad thing.. Good to be friends with people who have been there and done that..
Nice article, Brett! I'll bookmark it. I have never used either the 'mode' or up/downshifted. Since most of my driving is up 7% grades, should I just switch to 'Economy' and leave it there unless a burst is needed? I'd wonder, when to downshift? I notice all my gauges show nothing out of spec. Thanks, M ^.^d
Mike,
It takes a reasonable amount of "technical" driving and an appreciation for machinery to know the difference.
Again, no right or wrong ways, but a sensitive, knowledgeable drive CAN do better than "automatic".
To drive manually in 7% grades you need to know the rpm's at peak torque. Downshift when rpm's fall below that point while at WOT. Upshift when rpm's approach max rpm for your engine. Or let the Allison worry about it.
Yup, there are some critical numbers every DP owner needs to know for their engine-- call you engine manufacturer with your engine serial number:
Peak torque RPM (don't run below this at high throttle positions)
Peak HP RPM (no reason to run above this RPM under load)
Max RPM no load (important for descent where the engine is OK running at higher speed, since it is not working-- in some cases this is 300 RPM above peak HP!)
Without all these, you can not make wise decisions for technical driving.
Reading and learning all the time.
Thanks Brett
Also max braking RPM which is often 10% above that under power.
I agree that this is very informative article and I have learned a lot too. I have always just left it in the Economy Mode and downshifted manually in the mountains but it can certainly help improve the way I do it. Thanks Brett!!!
Now that my head is immersed in stuff I had no idea I might need, one more question: What is a "DP owner" ? :help:
DP= Diesel Pusher
You knew that Mike ;D ;D
There are SO MANY abbreviations: the obvious stumped me! :facepalm: