Learnt a bitter lesson with Comfort mode (1 Viewer)

[AtinLango]

I mostly drive with TEMS set to number 3, but i occasionally change to 1 or 2 for more comfort.

So yesterday i set it to 2 as i was on some pot-holed road. I was obviously driving extrememy slowly. When i entered a pothole, my head badly knocked against the car door. Couldnt believe it. Never happened before. This should not have happened if i had set TEMS to 3.

Leant a bitter lesson.

Question: is this indicative of a problem with the system?

 

[excessive]

is TEMS the same as AHC or something different?

 

[suprarx7nut]

is TEMS the same as AHC or something different?

Same thing. AHC is the height component of the system. AVS is the variable damping component. TEMS is Toyota's acronym for electronic suspension which encompasses AHC, AVS and a few other systems across multiple vehicles. TEMS dates back to 1986 when they put electronically adjustable shocks in the MK3 Supra.

 

[AtinLango]

In the LC 100, i know that

is TEMS the same as AHC or something different?

TEMS is the one managed using the Comfort-Sport knob.

So if you change the Comfort-Sport level, you are managing TEMS. I had even ever used other Toyota TEMS cars before my current LC 100.

I used to know TEMS in my earlier Toyotas as Toyota Electronic Modulated Suspension.

 

[excessive]

wow, that is completely different than the US market 100 series.

 

[2001LC]

I mostly drive with TEMS set to number 3, but i occasionally change to 1 or 2 for more comfort.

So yesterday i set it to 2 as i was on some pot-holed road. I was obviously driving extrememy slowly. When i entered a pothole, my head badly knocked against the car door. Couldnt believe it. Never happened before. This should not have happened if i had set TEMS to 3.

Leant a bitter lesson.

Question: is this indicative of a problem with the system?

Maybe!

Such a violented banging of the head, form pothole. Either a very nasty pothole or perhaps a blown globe.

A test for blown globe:
Find a bump in otherwise smooth road, like a speed bump. Where you can drive over bump, one tire at a time with other 3 on smooth road. If while driving over bump, only one tire/point results in violent head banger. That's your blown globe.

 

[AtinLango]

Maybe!

Such a violented banging of the head, form pothole. Either a very nasty pothole or perhaps a blown globe.

A test for blown globe:
Find a bump in otherwise smooth road, like a speed bump. Where you can drive over bump, one tire at a time with other 3 on smooth road. If while driving over bump, only one tire/point results in violent head banger. That's your blown globe.

Unlikely blown globe. Just today driving on a worse pot-holed road using a Mitsubishi pajero sport, i neaely got another head bang. I was only more cautious so i didnt bang the head this time.

I called my friend to narrate the experience and he said it has happened to him many times. He drives a non AHC/TEMS car. Actually he was in my passenger seat when i banged my head last time. For him he never banged. I think it was much more of my reaction that caused me to bang.

I recall even in the past the LC would give some of my my passengers hard time when set to Comfort on a pothole (note that i never ever drive fast over potholes). I would immediately set back to 3 and all would be well.

It is just a bad coincidence i am driving on bad short stretches of road this week, otherwise i normally drive on smooth roads only.

 

[AtinLango]

I have just recalled reading somewhere, i think in the manual, that you should use comfort level 3 when on rough road.

I think Comfort levels 1 and 2 are only safe to use when driving slowly on good road. In any other condition, it does not appear safe. I only knew this too well on highways where i always use 3 or 4.

 

[ClassyJalopy]

My truck is heavy (at 7000 lbs ~ 3175 KGs). Even with all new globes and bushings everywhere and non-AHC springs in the back, comfort 1 and 2 and nearly useless in almost all cases. I keep it at position 3 in the city and position 4 on highway.

Even though the pressures are all in spec, I have wondered if my AHC front TBs are overwhelmed by dynamic load and if I should try the non-AHC TBs to improve the ride control?

 

[2001LC]

It's recommended typically, soft shocks or AHC (1) setting on the rocks/rough road.

When installing adjustable shocks, in non AHC. Manufacture recommend low setting on the rocks. Higher or stiff setting, is for HWY/smooth roads.
Why: Reduce shock/impact to shocks, bushings and passages.

2003LX OM:
1 For driving on a bumpy road
2 For ordinary driving such as in the city traffic
3 For moderate high speed driving
4 For sporty type driving such as on winding mountain roads and high speed driving
We recommend you to select the mode 2 for ordinary driving. The damping effect will be changed automatically to provide good riding comfort.

 

[2001LC]

Unlikely blown globe. Just today driving on a worse pot-holed road using a Mitsubishi pajero sport, i neaely got another head bang. I was only more cautious so i didnt bang the head this time.

I called my friend to narrate the experience and he said it has happened to him many times. He drives a non AHC/TEMS car. Actually he was in my passenger seat when i banged my head last time. For him he never banged. I think it was much more of my reaction that caused me to bang.

I recall even in the past the LC would give some of my my passengers hard time when set to Comfort on a pothole (note that i never ever drive fast over potholes). I would immediately set back to 3 and all would be well.

It is just a bad coincidence i am driving on bad short stretches of road this week, otherwise i normally drive on smooth roads only.

We'll then, fix the road!
Tire & tire PSI, also make a difference. But for sure use #1 low comfort (softest) AHC setting

 

[suprarx7nut]

My truck is heavy (at 7000 lbs ~ 3175 KGs). Even with all new globes and bushings everywhere and non-AHC springs in the back, comfort 1 and 2 and nearly useless in almost all cases. I keep it at position 3 in the city and position 4 on highway.

Even though the pressures are all in spec, I have wondered if my AHC front TBs are overwhelmed by dynamic load and if I should try the non-AHC TBs to improve the ride control?

This is to be expected. As you increase weight, the car automatically increases the spring rate (either via AHC hydraulic pressure or via you manually cranking torsion bars or swapping torsion bars). The damping however, is not altered. As you increase spring rate, you should increase damping. For AHC this means you just move up a setting on that dial.

I use comfort (setting 1) for most everything except highway driving. Then it's on Sport 1 or 2. If the road is rough, I'm definitely sitting in comfort 1 all day.

 

[ClassyJalopy]

This is to be expected. As you increase weight, the car automatically increases the spring rate (either via AHC hydraulic pressure or via you manually cranking torsion bars or swapping torsion bars). The damping however, is not altered. As you increase spring rate, you should increase damping. For AHC this means you just move up a setting on that dial.

I use comfort (setting 1) for most everything except highway driving. Then it's on Sport 1 or 2. If the road is rough, I'm definitely sitting in comfort 1 all day.

Hmm that means I no longer have the Comfort 1 and 2 available to me. Is there a way to remap the settings on the switch to what is 3 now, become 1 and so on?

 

[suprarx7nut]

Hmm that means I no longer have the Comfort 1 and 2 available to me. Is there a way to remap the settings on the switch to what is 3 now, become 1 and so on?

I think it's more like you've lost Sport 2 (and maybe sport 1). You've lost the stiffer settings and gained a balanced amount of additional comfort settings.

I'm not aware of any off-the-shelf way to remap/recalibrate that. You'd need to tweak the response of the actuators or replace them with something even more restrictive. Not a completely crazy thing, just something that would need to be developed by a high-end shock-tuning sort of company or an OEM.

Alternatively, upgrade all the armor to aluminum and you'd probably shave 400-500 lbs while maintaining protection and get a setting on your dial back.

 

[Moridinbg]

100 series do not adjust spring rate. This is 200 series AHC
Our old timer system only adjusts damping, which is a mix between compression and rebound.

Comfort 1/2, Sport 1/2 adjust the baseline level - step in Techstream.

The settings are 4/2, 4/4, 8/8, 12/12 front/rear steps from Comfort 1 to Sport 2. Maximum is 16/16. At 0/0 the car is super undamped - low compression, so suspension blows through travel, at 16/16 it is very firm. Those are baseline levels and the system adjusts them continuously as you drive. You can see that in real time in TS (drive safely!), just make a custom list that shows only the steps values, so that it refreshes quick - the full values list refreshes in ~4000ms, 2-3 values refresh in ~500ms.
Even if you drive in C1, if you hit something the step value will rise quickly, even to 16/16, just from a lower value.

The difference between the different settings is subtle and I would say that if you banged your head in C2, you would have done the same in S2 too, with even harsher banging.

The working principles are very well explained in the car introduction documents - https://lc100e.github.io/pdf/ncf/ncf147e/m_ch_0196.pdf

 

[Mike NXP]

Maybe before you go out on your next drive you need to suit up....

 

[AtinLango]

Maybe before you go out on your next drive you need to suit up....

View attachment 3468870

Thats overkill. Maybe if one is driving dangerously.