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Naks

Member Since: 27 Jan 2009
Location: Stellenbosch, ZA
Posts: 2645

2010 Defender 90 Puma 2.4 SW Alpine White

tatra805 wrote:
And i know that mine (with TC) will keep anti-stalling in low even when I press the brake for longer time, eg a steep decent in 2nd low which should have been taken in 1st low and thus with a bit of brake assist to reduce the speed.

Indeed, but during these descents you are not using the accelerator, so there is no driver throttle input to the ECU? --
2010 Defender Puma 90 + BAS remap + Alive IC + Slickshift + Ashcroft ATB rear
2015 Range Rover Sport V8 Supercharged

Defender Puma Workshop Manual: https://bit.ly/2zZ1en9
Discovery 4 Workshop Manual: https://bit.ly/2zXrtKO
Range Rover/Sport L320/L322/L494 Workshop Manual: https://bit.ly/2zc58JQ

11th Jul 2012 12:29pm

tatra805

Member Since: 16 Aug 2011
Location: Dolany
Posts: 436

2008 Defender 110 Puma 2.4 CSW Bonatti Grey

naks, correct but the ECU is telling the engine to accelerate (engage anti-stall) despite the driver input indicating he wants to slow down the car.

I am convinced the drive by wire technology must have a safety net when conflicting signals occur, whereas the brake signal has the priority above the accelerator.

Now if this system would work identically with difflock engaged when the anti-stall is working ecu should disable the anti-stall if you press the brake longer than 5sec. but it doesnt

therefore i suspect this conflicting signals priority thing to be disabled with difflock engaged.

If so, this solves the ATB diff issue (i have them also) of blackwolf.

edit: It could be that the anti-stall has priority over brake signal (or is ignored in the programming) but this would create unsafe situations in normal driving when pressing the brake without pushing the clutch eg in a panic reaction. Anti-stall would keep propelling the car even when you are braking... if this is the case i consider it very poor programming and an issue (as a failure in the brake system (eg accident) could mean brakes are not able to overcome power of engine to stall it)

As a sidenote it's not the best idea not to use your center difflock offroad as the LT230 center diff is strong when locked but was not designed for prolonged exposure to different speeds between front and back axle (so offroad unlocked)

11th Jul 2012 12:44pm

Naks

Member Since: 27 Jan 2009
Location: Stellenbosch, ZA
Posts: 2645

tatra805 wrote:
therefore i suspect this conflicting signals priority thing to be disabled with difflock engaged.

Pretty sure that is the case, LR is not *that* stupid

Quote:
As a sidenote it's not the best idea not to use your center difflock offroad as the LT230 center diff is strong when locked but was not designed for prolonged exposure to different speeds between front and back axle (so offroad unlocked)

Eh? I disagree, as soon as you step off the black stuff, put your CDL on. I have driven for over a week with the CDL locked in various parks, no issues whatsoever.

Also, with the CDL locked, front axle speed = rear axle speed

--
2010 Defender Puma 90 + BAS remap + Alive IC + Slickshift + Ashcroft ATB rear
2015 Range Rover Sport V8 Supercharged

Defender Puma Workshop Manual: https://bit.ly/2zZ1en9
Discovery 4 Workshop Manual: https://bit.ly/2zXrtKO
Range Rover/Sport L320/L322/L494 Workshop Manual: https://bit.ly/2zc58JQ

11th Jul 2012 1:15pm

tatra805

Member Since: 16 Aug 2011
Location: Dolany
Posts: 436

Quote:
Eh? I disagree, as soon as you step off the black stuff, put your CDL on. I have driven for over a week with the CDL locked in various parks, no issues whatsoever.

Also, with the CDL locked, front axle speed = rear axle speed

eh... yep! thats what i said didn't i?

Quote:
it's not the best idea not to use your center difflock offroad

and about LR being "that" stupid i am.... let's say... open for arguments

11th Jul 2012 1:39pm

blackwolf

Member Since: 03 Nov 2009
Location: South West England
Posts: 17451

2007 Defender 110 Puma 2.4 DCPU Stornoway Grey

Ok, done some testing on my way home from work. It is a speed-related feature.

If you apply the brakes at 10mph or below the throttle is not affected; at 15mph or above power is killed after about 5 seconds. Transfer gears and CDL don't appear to be factors.

Which actually seems to be a very sensible set-up in fact, and one I have no problems with now I know!

11th Jul 2012 4:37pm

4wheeler

Member Since: 13 Apr 2010
Location: Melbourne
Posts: 87

2013 Defender 110 Puma 2.2 SW Chawton White

Just tried this in my 2011 Ford Transit with the 2.4 TDCi. Power is cut after about 5 seconds at normal speeds so it is engine management related. Haven't checked at low speeds.

12th Jul 2012 5:20am

wslr

Member Since: 18 Jul 2010
Location: Wellington, Somerset
Posts: 581

With the anti-stall feature on the Defender, this video makes interesting watching as the 110 drops down a slope.

http://www.youtube.com/watch?v=PMhOhT5nwZk

Issue starts at around 4:10. Not sure if this is relevant to our discussion?

12th Jul 2012 6:58am

Naks

Member Since: 27 Jan 2009
Location: Stellenbosch, ZA
Posts: 2645

wslr wrote:
With the anti-stall feature on the Defender, this video makes interesting watching as the 110 drops down a slope. http://www.youtube.com/watch?v=PMhOhT5nwZk Issue starts at around 4:10. Not sure if this is relevant to our discussion?

That was the driver doing it on purpose to illustrate what could happen. IRL in 1st low, you brake during a descent and it does not accelerate

--
2010 Defender Puma 90 + BAS remap + Alive IC + Slickshift + Ashcroft ATB rear
2015 Range Rover Sport V8 Supercharged

Defender Puma Workshop Manual: https://bit.ly/2zZ1en9
Discovery 4 Workshop Manual: https://bit.ly/2zXrtKO
Range Rover/Sport L320/L322/L494 Workshop Manual: https://bit.ly/2zc58JQ

12th Jul 2012 9:55am

Ashley110

Member Since: 21 Mar 2012
Location: Johannesburg
Posts: 7

2012 Defender 110 Puma 2.2 SW Alpine White

I can down Sani and on switch backs etc I used 1 and 2 Low on engine compression.

The car did not even vaguely respond like it does in that video.

12th Jul 2012 7:15pm

Caterham

Member Since: 06 Nov 2008
Location: Birmingham
Posts: 6300

2011 Defender 110 Puma 2.4 XS CSW Stornoway Grey

blackwolf wrote:
LandRoverAnorak wrote:
Surely, the ECU is just detecting the brake signal rather than what the diffs or wheels are doing?

True, but my point is that for a torque-biasing diff to work there must be some load on both wheels. If one wheel is airborne, for example, all the power will be transmitted to it, as it would with an open diff. The accepted technique to overcome this is to apply the brakes lightly to load the spinning halfshaft, which will then cause a proportionally greater torque in the non-spinning side (the operation of torque biasing diffs is a little counterintuitive, but in essence there must be some resistance to movement in both halfshafts). However it appears that with a Puma the engine will de-fuel and rev down after five seconds, which may not be optimal. My Defender does not have TC, which will inevitably alter the situation.

From the electical manual it appears that there are two inputs to the ECM from the brake light switch; there is an tapping from the actual brake light circuit (input B001 on C0872-E3 from C0075R-2) and one which is dedicated (input B002 on C0872-F3 from C0029R-2). It may be that disconnecting one or other (or both) of these will disable this feature, but it is hard to predict what if any side effects this may have. Anyone like to become the guinea pig?

BW you mentioned the brake connection c0075r-2

Can you explain what is also connected a 'header (k109)'. Kind it's an point then can't see how this works?

23rd Jun 2015 7:33pm

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