Anyone know if there is a way that I can add a "four wheel drive indicator light"? It drive me nuts not knowing when or if four wheel drive is kicked in.
I hade a Chevy Blazer before and always knew if I had it in auto-four wheel,
Manual-four wheel or two wheel.

Its on all the time so just connect any light to 12 volts :)

I guess what you really want to know is which wheel is slipping and when right?

Yeah. I guess I'm not sure how it works. Are you saying it's on all the time but turns off on any wheel that slips?

"Real Time 4WD sends power to the rear wheels when the primary front-wheel-drive system experiences slippage. The system consists of a power take off (PTO) from the transmission that distributes torque to a propeller shaft that runs to the rear differential. The rear differential contains two internal hydraulic pumps -one driven by the propeller shaft and one driven by the rear wheels - that circulate fluid through an internal multi-plate clutch system. When wheel slippage occurs, the flow rate is greater from the propeller shaft pump and forces the clutches to progressively engage, sending up to 70 percent of the torque to the rear wheels in slick conditions and 30 percent in dry conditions. The system operates automatically and only when needed, requiring no intervention on behalf of the driver to activate. "

My understanding is that the Honda RT4WD system transmits torque to the rear wheels by tighting up on a clutch pack. This would produce heat build up in the Honda Dual Pump fluid. If the heat build up is too much (such as with a lot of wheel spinning) a thermal cutoff is activated, and the system reverts to 2wd until it cools off.

It might, then, be possible to detect a heat buildup in the torque-control differential case, and infer from that, that torque is being sent to the rear wheels. I think this would require attaching some sort of heat sensor to the case, and recording the temperature in variety of conditions, and then programing a computer to distingish among different causes of temperature change. It would not give an immediate indication, and may not detect short periods of torque transfer. It could also be programmed to identify thermal cutoff.

Anyone got a PDA with remote temperature sensor?

paulj

I think that'd be too unreliable. I wonder if there are test ports on the unit that can be tapped for *pressure* or clutch location sensing.

-brendan

I agree that interpreting the temperature data would be iffy, however I can think of no other way of getting data from the unit without voiding the warnanty. The thermal mass of the casing might be quite large. Quite likely Honda engineers have installed sensors in one or more of these units, but the production model shows no sign of a test port or wiring. I just crawled under my Element and took some pictures.

The case consists of 3 parts.
- The forward bell shaped housing with the propeller shaft entering at the front end,
- a central, roughly cylindrical piece,
- the differential backend, with main mounting bracket.

The drive axles exit through the joint of the back 2 pieces. On the driver's side of the center piece there are two plugs (brass? large inset square socket), probably for draining oil (the bottom one) and refilling. Next to the top plug are the letters DPSF (dual pump .. fluid?).

A closer look at the pictures shows there is a smaller circular structure above the DPSF plug, but I can't tell whether it is removable. It looks more like it is a blind treaded bolt hole.

According to a diagram of the rear-differential assmbly (http://www.quebeccrv.com/other/rtawd.pdf) the clutch pack and oil pumps are all in the smooth forward bell housing. The oil plugs open into the bearing space between the clutch/pump assembly and the differential.

Anyways, I have not read of any port or sensor inside the dual pump unit. Assuming it is as trouble free as the typical differential, Honda has little incentive to provide testing access other than for changing the fluid.

One might also be able to deduce from ABS wheel sensor data when the rear wheels are receiving torque - that is, average the same axle data in the same way the differential would, and compare the two axle averages. Since I don't have ABS I'd have to use some sort of rotation sensor on the properller shaft and the 2 drive shafts
e.g.
average the 2 drive shafts. If this is more than 2.5% different from the propeller shaft and (not brakes and forward rotation), then 4wd is likely.

The clutch pack is activated (at least partially) if the pumping rate of the forward pump is larger than the pumping rate of the rear. The rear is sized 2.5% larger, so the front has to be rotating a bit faster than the rear to pump faster - i.e. the front wheels (as averaged by the differential) have to be spinning some compared to the rear.


paulj

As a matter of curiosity I estimated what the speed difference would be if one tire was the temporary spare.

The Wrangler HP has a diameter of 27.7" (tirerack data)
145/90/16 spare is 26.3"
94.86% of regular tire

If the differential does a simple average, the axle with the spare spins 1/.974 = 1.027 times faster than the axle with 2 regular tires. This is right on the border line of triggering the 4wd - at least until the thermal cutoff is triggered. I wonder if it is better to put the temporary spare on the rear axle if possible? The manual doesn't mention anything like that. This of course, does not take into account wear of the front tires, different tire pressures, and spring pressure in the clutch pack. Also with a slight speed difference, the clutch pack may engage only lightly, sending a small amount of torque to the rear.

paulj

DPSF = "Dual Pump System" or DPS Fluid.

Googled DPSF, saw a reference to DPS4WD on a japanese page:

http://www.hondanet.co.jp/verno-yamato/html/060_m_oil.html

...then googled DPS Honda. :) It appears that DPS is the name of the AWD system in Japan.

An aside: speaking of Japan, what's this???

http://www.purehonda.com/cool/japanonly/jwjinfo.html

Ok, I'll take a look at the service manual, but I suppose I'll find the same info as you did: no way to peek inside the unit...

-brendan

There was a recent thread on one of the crv boards about this problem: they put the wrong tire on (same brand/line/size, but the manufacturer made them differently for 3 vehicles) and their AWD was always engaging. Ick.

With wear it's likely that the standard tires will be slightly smaller, bringing the ratios to within the 2.5% tolerance, right?

-brendan

i'm sure that someone (paulj?) knows for sure, but i'm pretty sure that there is no electrical circuit for the awd, its purely mechanical.

so there is nothing to 'tap into'

yeah u would probally need to make ur own

Why does everyone have such a hard-on for a light that shows when the AWD is engaged? Give it a rest, that crap is for ancient 4WD trucks. I'm certain if Honda felt that you needed to know when AWD was engaged, they would have put a light there.

Thats the problem with society, everyone wants light up crap...windshield washer nozzles, cell phone batteries/antennas and so forth. Idiot lights are called so for a reason.

I little light would be neat but I'd rather have a siren, a really LOUD one and an oxygen mask to fall from the overhead bin, oh, and auto-inflate pontoons, oh yeah, and something that goes, "PING!"

Why does everyone have such a hard-on for a light that shows when the AWD is engaged? Give it a rest, that crap is for ancient 4WD trucks. I'm certain if Honda felt that you needed to know when AWD was engaged, they would have put a light there.

Thats the problem with society, everyone wants light up crap...windshield washer nozzles, cell phone batteries/antennas and so forth. Idiot lights are called so for a reason.

It would be a neat mod! i meen comeon... whats cooler than a light that comes on when you spin the wheels :) also you would know if your awd id malfunctioning. Or if its on too long.... stuff like that :evil:

Yeah, its a neat idea until someone is on a snowy or icy road and the AWD engages and disengages frantically, flashing a light and causing someone to have an epileptic siezure and crash.

I generally like my vehicles to have nothing more than it needs to go and stop, all the rest is BS.

Thats also why I believe most people drive like retards...the car does all the work nowadays, there's almost no real driving skill involved. I used to do alot of racing at the local oval track years ago, so I consider myself to be a highly skilled driver. ( whoops, got a little off topic there )

Yeah, its a neat idea until someone is on a snowy or icy road and the AWD engages and disengages frantically, flashing a light and causing someone to have an epileptic siezure and crash.

I generally like my vehicles to have nothing more than it needs to go and stop, all the rest is BS.

Thats also why I believe most people drive like retards...the car does all the work nowadays, there's almost no real driving skill involved. I used to do alot of racing at the local oval track years ago, so I consider myself to be a highly skilled driver. ( whoops, got a little off topic there )

well when red lights are out they blink too :) and the do not cross blinkking hands are the same too. so to summ it all up, if u have seasures from videogames, lights or etc,,, dont drive :)

Could you define 'engaged'? What would be the criteria?

Take a look at the graph on page 6 of the QuebecCRV document (should be a link in the off-road section). There is a nice pair of graphs, showing relative torque being sent to front and rear axles during a slippery start. In a second and half, the amount of torque sent to the rear wheels rises rapidly to 70% then tapers off to 30%. I suspect these graphs are based on a heavily instrument test unit, not a production one.

What I'd suggest doing is study up on the ABS system, and figure out a way of tapping into its data about the spin rate of the 4 wheels. With some clever programming you should be to simulate the action of the rt4wd unit, a from that generate a display indicating 'engagement'.

paulj

thanks paulJ i have been directed away from this :).... im not too good a wiring at all! oh well, it was a thought

I think we need a gage or maybe a really detailed backlit LCD graph since its not just off or on AWD. Something that could really take ALL your attention away from watching THE ROAD, which of course there is really no reason to be using your FULL attention on the road if the AWD is coming on.....

Gotta save your focus for PRIORITIES...like drinking your starbucks WHILE dialing your cell phone and watching the incoming pics on your cell phone, and punching in the sat station, while driving down that icey road....

maybe a heads up display of all vital functions - front v rear torque, right and left differential action, torque multiplication factor in the transmission, oil temperature ... :)

I once proposed taping a thermister to the rt4wd casing, on the theory that the oil would heat up when the clutch tightens up. After all, there is a thermal cutoff. But, in ordinary use, the rear wheels torque only for a few seconds at a time, so this wouldn't work.

A microphone taped to the case might be a better idea - since one way I have detected rear traction is by its sound. Amplify the sound and send it to a bank of flashing LEDs :-)

paulj

easyier said then done!

A microphone taped to the case might be a better idea - since one way I have detected rear traction is by its sound. Amplify the sound and send it to a bank of flashing LEDs :-)

LOL, so rough roads are out... as is offroading...

Maybe even have in LARGE LETTERS "AWD ON" "AWD OFF" lights on the back of the car ligting up through back window - to entartain other drivers in the blizzard :)

...something that goes, "PING!"

I thought scientific progress went "BOINK".

While a realtime indication of rear wheel torque may not be that useful, some sort of historical record might. If the front wheels are spinning, my attention is likely to be focused on the immediate tasks of driving - steering, gas, brakes. However after the fact, I might well wonder whether the rear wheels played a role in recent events. We get quite a few posts in which people wonder whether the awd system is working, posts claiming that 'I tried to burn rubber, and the rear wheels didn't do anything' or 'I buried the front end in quicksand, and the rear wheels couldn't get me out'.

My microphone idea might make a good signal processing project for an engineering student. There must be microphones than can be used to pickup vibrations in machinery. Hook one up to a laptop, drive around a bit trying to spin the front wheels, and then identify the signal that is indicative of clutch activation in the rt4wd unit. All that is left is to program a signal processor to isolate this type of signal.

paulj

hey all,

i was thinking a while ago... do any of you think it would be possible to install a light that illuminates when the 4wd is engaged? i meen i can feel when its on but a light would be cool to any thoughts? :evil:

I wish there was a way to know when the ELement is in 4WD also. This feature should come standard from Honda.

LittleDogBox

LittleDogBox

If Honda did provide such a light, when would you expect it to come on, and for how long? Any ideas of where it should be placed? Would you drive the Element differently?

Anyone interested in a differential light, one that would light up when the differential is on?

paulj

LittleDogBox

If Honda did provide such a light, when would you expect it to come on, and for how long? Any ideas of where it should be placed? Would you drive the Element differently?

Anyone interested in a differential light, one that would light up when the differential is on?

paulj

well paul, my dad has a land cruiser... and as most of us know it had a center diff lock, now when he goes off roading and he decided to enage it, there is a light that goes on, so he pushes the button and the light comes on. then when he decides to tunr it off, he pushes the button and nothing happens, the light is still on. It takes about 5 min for the diff to finally unlock, aslong as you drive relitavly straight. and during all that time the light is on. so maybe if there was a HONDA manufactured light if you just spin your wheels for like 2 seconds, maybe it would still satay on. now remember the land cruiser s a toyota not a honda but still....

My Nissan truck had a light that would come on when 4WD was on.
You also had to slow down below 25mph before shifting it into 4WD, and then you had to back up at least 10 feet to unlock this "automatic 4WD" hubs. Which is really no fun at all when getting on and off freeways that are icey right up through the on ramp, and then DRY on the freeway.

I sooooooo much prefer the Honda Element's SIMPLE approach. At first I was put off by not having an idiot light telling me it was on, but I soon realized the AWD only came on as needed and WOULD come on as needed, and that is often for just a pslit second as I rip out into that narrow gap in heavy traffic in a heavy rain. I finally realized it would be IRRITATING and distracting to have a light flashing on and off all the time in dicey driving conditions.

It does take a little bit to get into the mindset of "keep it simple" though.

i dunno might be cool addition.. :evil:

A light associated with a control certainly makes sense. I have 4x4 chevy pickup with 3 positions for the transfer case control - 2H, 4H, 4L, and corresponding lights on a diagram of the 4 wheels. Going into 4h lights up all 4 wheels, and as with the Toyota, switching back to 2H doesn't change the lights until something in the autolocking front hubs disengages.

So moving the control to 4H changes some gear settings in the transfer case, activating the forward drive shaft. That in turn locks a freewheeling mechanism in the front wheels or axles. Presumably there is a switch or sensor in this freewheeling mechanism that activates the lights by the control. And these lights don't change until the mechanism unlocks.

With even earlier 4x4 systems, you had get out of the car, turn something on each front hub to lock them. There were no lights to tell you whether the hubs were locked or not. With a system like this it was easy to forget to lock or unlock the hubs, with the resulting failure to turn on the 4wd, or excessive wear and drag in the front drive system.

So the lights on my pickup are useful in telling me the state of the locking hubs. If the 4wd lights stay on after I switch back to 2H, I know I need to let up on the power so the hubs can unlock. As long as I am in 4H or 4L I need to be careful about driving on dry pavement to avoid 'windup'. The lights keep me from abusing the system.

Another traditional use of indicator lights on the dash is to warn of faults - the check engine light (usually faults in the emissions system), srs light (air bag fault), battery and oil pressure lights, low fuel lights.

While an 'awd fault' light on the Element might make some sense, it would have to be triggered by some well defined failure mechanism, such as low oil level in the combined rt4wd and rear differential unit. Another fault trigger could be activation of the thermal cutoff. Yet another trigger could be the pressure relief valve, the one the prevents sending excessive torque to the rear wheels. All of these would require 3 additional holes in the awd unit, 3 sensors in those holes, 3 gaskets that could leak oil, and 3 sets of wiring to the ECU, plus further programming. Considering that currently there are no wires the awd unit, this would be a serious increment in complexity. Since the rear wheel torque is not needed for normal driving, this extra fault warning system probably is not worth it.

If you are really serious about needing awd indicators, I'd suggest trading your Element in for a Pilot, MDX, or other car with an electronically controlled system (see the above MDX post). Or you could wait for the next generation awd system that is supposed to first appear in the CRV.

paulj

Pondering all these proposals for a "handy" AWD indicator light "system", and reminiscing over past 4WD systems I have owned and known, I am really starting to appreciate the "keep it simple" approach of the Element.

One other thing to consider, as pointed out in various AWD threads in this forum, is the most "in the ditch" drivers on the road, are those people driving those 4WD/AWD SUV's and Trucks with all the lights and indicators, figuring that sticks them to ice somehow.

Have you ever considered that the safest way to be driving your car in snowy and slick conditions would be to be wondering if you really are in 4WD, so you tend to drive it more like its 2WD? I find myself falling into this frame of mind occasionally. At first I was a bit irritated by that effect, but now I realize it makes me a MUCH SAFER DRIVER.

They have done us a favor folks. Less to go wrong , including that hardware problem of a nut loose in the driver's seat.....

I have been driving my Element for a year and like it MORE as time goes on.

Is there some other reactive system that has an indicator light? The only other one I'm familar with is the RAV4. That splits power evenly to all 4 wheels in normal conditions, but shifts some front and back when there is slippage. There is no light to indicate such a shift.

I've test driven the Santa Fe; I don't recall any such light. Does Subaru have any such light? The Escape in nonlock mode? Saturn VUE? It would be easier to talk about the value of such a light if we had some real world example to work from.

paulj

Ok, I might sound like a dick when I say this, but I'm not trying to.

You all are talking about other cars/trucks that when you "shift" them into 4wheel drive, a light lights up.

Well if you were to install a light in the Element that tells you when the system is on, just wire it to your ignition switch, it is always on.

The AWD system is always working and engages when needed.

And a light that would come on when it engages would prob piss most people off. I wouldn't want something blinking at me all the time. DO you know how often the system can actuate and you don't know it?

Stupid-question time. Should prolly look it up in the owner's manual, but I'm feelin' a bit lazy. :grin: Anyways, when the AWD drive engages, is there any way to tell? Ala, a light on the dash, some discernable sound, etc, etc? Don't plan on being in a situation to need it anytime soon, but you never know...

Stupid-question time. Should prolly look it up in the owner's manual, but I'm feelin' a bit lazy. :grin: Anyways, when the AWD drive engages, is there any way to tell? Ala, a light on the dash, some discernable sound, etc, etc? Don't plan on being in a situation to need it anytime soon, but you never know...

Well, if you don't get stuck, that your first good sign! :)

There is no dash light or sound to let you know when it engages, but you can sort of "feel" it kick in if the road conditions are very slippery. Basically the Honda 4WD (yea, Honda calls it 4WD) system operates much like the Subaru AWD system "transfers power from the wheels that slip to the wheels that grip".

The 4WD system is always engaged, only the front wheels get like 70% power while the rear gets 30% under normal conditions. If you run into a slippery situation, that ratio is automatically and instantly adjusted to compensate.

No, there is no way to disengage the 4WD system; a caveat that I dislike. However, I must say I'm EXTREMELY happy with the way the 4WD system behaves on slippery roads! I've not gotten stuck yet, but then I tend to want to stay ON the road....

And that, in a nutshell, is what the Honda Element 4WD system is intended for. It keeps you ON the road; it is not meant for serious off-roading.

Hope that helps! :)

LEGO

I'm well versed in the 4 wheel drive system on the E, but dont know how to tell whether the 4 wheel drive has automatically kicked in or not. is there some sort of display indicator that lets you know the E has switched from 2 wheel drive to 4 wheel drive?

thanx

greygoose

No there's not, I've already whined about this before.

The indicator is when your wheels stop slipping and you move forward :roll:

Multiple Threads Merged.


I am still looking...But there is a couple more threads out there discussing the addition of a dash board indicator.....More correctly why it cannot be added.

My Isuzu Trooper had a visual of all 4 wheels in a gauge. When in the mode to only send torque to wheels as slip was detected, wheels would light fore and aft as used and it was very helpful in navigating offroad. It wasn't ciritical info, but it was helpful...especially if the amount of slippage (say in ice or deep mud) was unknown, I could watch for the front wheels needing to help (rwd truck otherwise) and know conditions were worsening on the road/path.

I would like something for the E but I'm a bit of a freak for lights and vehicle info. When I had an aftermarket sound system in my old 85 Accord hatchback, I wired indicator lights for the temp actuated cooling fans to the front dash! So yeah, I may not be a standardarized opinion here.

Anyway, I don't really see a quick measurement spot to tag for an indicator lamp. System is too automated without electrical assistance to easily tap...and I'll take that instead thanks.

I see a lot of folks asking the same question as someone two posts above them. Read the thread! Your answers are in there already!

I see a lot of folks asking the same question as someone two posts above them. Read the thread! Your answers are in there already!


Most of them members that asked this question asked in new threads. The individual threads were merged into this one.