Landrover Discovery 4 transmission question

[Orwell boy]

All i really want to understand is the link between modern stop start discovery 4 (ad blue version), and the hill hold assist which all seems dependant on the auxilary stop start battery (housed under the bonnet drivers side ) ........As what i appear to have discovered is that if stop start isnt working (because of flat aux bat
ttery ) then there seems to be no hill hold assist (totally unafectected by hand brake) but the point you switch your boot from the foot brake to the accelerator (without handbrake on ) at the bottom of the slipway

Just looking for an engineering explanation of the modern world as i dont really understand stop start tech so therefore cant rationally think how these features
could effect each other but my experience says they do ,or did i imagine it ?

[paintman]

As it's an auto why bother switching your foot from the brake pedal to the accelerator?
Use your left foot on the brake pedal & your right foot on the accelerator.

Mine's an ancient Range Rover Classic auto so I don't have all the electrickery stuff but using both feet makes it much easier when low speed manouevering in tight spaces esp with a trailer hooked up & on slips.
(ETA works well offroading too.)

I don't use both feet when driving it normally.

I use the handbrake - on these it works on the rear propshaft - and let it settle on the brake before putting it in Park. I also put a chock behind one of the wheels. If you use a short length of cord round the handle of the chock & loop it over a convenient part of the car you can drive away & then stop when convenient to pick up the chock.

[beamishken]

Originally Posted by Orwell boy

All i really want to understand is the link between modern stop start discovery 4 (ad blue version), and the hill hold assist which all seems dependant on the auxilary stop start battery (housed under the bonnet drivers side ) ........As what i appear to have discovered is that if stop start isnt working (because of flat aux bat
ttery ) then there seems to be no hill hold assist (totally unafectected by hand brake) but the point you switch your boot from the foot brake to the accelerator (without handbrake on ) at the bottom of the slipway

Just looking for an engineering explanation of the modern world as i dont really understand stop start tech so therefore cant rationally think how these features
could effect each other but my experience says they do ,or did i imagine it ?

Its probably when the vehicle senses a low battery the system starts to shut down "none essential" features to conserve the battery for more important features. Many cars with intelligent battery systems do this & I'd suspect thats whats happening here. No idea why it needs an extra battery though most stop start cars just have the one battery but then landrovers always were odd[emoji6]

Sent from my SM-G950F using RIB Net mobile app

[Orwell boy]

Originally Posted by beamishken

Its probably when the vehicle senses a low battery the system starts to shut down "none essential" features to conserve the battery for more important features. Many cars with intelligent battery systems do this & I'd suspect thats whats happening here. No idea why it needs an extra battery though most stop start cars just have the one battery but then landrovers always were odd[emoji6]

Sent from my SM-G950F using RIB Net mobile app

I guess your right thankyou ,its probhably as simple as that ,i think i may have been looking for a more complex answer ,however that was never going to happen ,its a landrover still the most useful learning for me was i discovered the "aux battery" which i think is in rangerovers as well ,hidden in the most unusual places ,even you tube hasnt got the full lowdown on disco 4 yet ,i hunted in 2 other landy forum suggested places before i found it ,not too mention i had a second new 019 (main) new battery because st start didnt work on the first new one after 6 months suggesting the dealer didnt know it existed either

[mick]

Originally Posted by Pikey Dave

On the Disco4 the “Hill Hold Assist” is provided by the parking brake, I.e. you put the parking brake on & it releases automatically when you put the gearbox into drive & move off. If you didn’t put the parking brake on to start with, it wouldn’t hold when you went into drive.
You shouldn’t be able to go from Park to Drive without having your foot on the brake.

You should never rely on “park” to hold the vehicle. As previously mentioned it’s just a pin that engages in the gear box. Always use the handbrake, in extreme circumstances have someone sat in the driver’s seat with their foot on the brake pedal. If you put it into park & then load up the vehicle all the weight is held on the locking pin & traps it. The solenoid isn’t powerful enough to disengage it then.

Or rope another D4 to the front [emoji16]🤦🏻*♂️

[mick]

Originally Posted by Orwell boy

Sorry folks ,what i wrote about from park to drive is rubbish sorry to mislead ,was just trying to show that it was the "hill hold" that was failing not the "park " position ,once you have selected drive it ussually alows me to move foot from brake pedal to accelerator while holding firm until forward motion ,......my way out was to go back to neutral and select low and then all happened as it should ,maybe i hadnt got the knob to drive !

To explain my no handbrake system this was based on my landrover offroad day that i recieved after buying my variuos landrovers ,

when i went i wasn,t that interested in off road driving however the one thing i wanted to solve was the implications of a poor handbrake on my steep home slipway (levington ) .......too this end i questioned the instructor re the ability of the park position on the gearbox ,he promptly took us to the hill climb demo ,,stopped half way up ,put the vehicle in park and we all got out on the slope (where we could barely stand up ) he said i would never need the handbrake ,and i accepted his knowledge and have never used the handbrake since ??,,,looks like poor info there then !

Poor info as others have said use PB it’s only a pin
Mine will roll back in drive on a steep slope if the reves are not high enough
Good tip get the gearbox flushed as well well worth it especially if you have extra warranty

[mick]

Originally Posted by Orwell boy

I guess your right thankyou ,its probhably as simple as that ,i think i may have been looking for a more complex answer ,however that was never going to happen ,its a landrover still the most useful learning for me was i discovered the "aux battery" which i think is in rangerovers as well ,hidden in the most unusual places ,even you tube hasnt got the full lowdown on disco 4 yet ,i hunted in 2 other landy forum suggested places before i found it ,not too mention i had a second new 019 (main) new battery because st start didnt work on the first new one after 6 months suggesting the dealer didnt know it existed either

Just turn the stop start off when your on the slip
Land Rover has a very keen battery low sensor

[Orwell boy]

[QUOTE=mick;848328]Just turn the stop start off when your on the slip
Land Rover has a very keen battery low sensor[/QUOTE

I think i can now quite confidently say that if the stop start system is non functional (in my case because the aux battery was knackered), whether turned on or off ,the Hill hold assist will not work when the high range is being used.However it does appear to work in low range !
I have now replaced the exide 15 a/h aux battery (located under the bonnet in front of the driver side ) ,and hill hold is now fully functional on the slip way
I think the modern hill hold facility is much closer related to stop start because it is a very similar need as when the engine has switched off at the lights on a steep slope still in drive ?

[mick]

[QUOTE=Orwell boy;848344]

Originally Posted by mick

Just turn the stop start off when your on the slip
Land Rover has a very keen battery low sensor[/QUOTE

I think i can now quite confidently say that if the stop start system is non functional (in my case because the aux battery was knackered), whether turned on or off ,the Hill hold assist will not work when the high range is being used.However it does appear to work in low range !
I have now replaced the exide 15 a/h aux battery (located under the bonnet in front of the driver side ) ,and hill hold is now fully functional on the slip way
I think the modern hill hold facility is much closer related to stop start because it is a very similar need as when the engine has switched off at the lights on a steep slope still in drive ?

From what I understand the second battery only runs the electronics in stop start mode, your better off not using stop start mode anyway all it does is fook your engine up

[Orwell boy]

[QUOTE=mick;848346]

Originally Posted by Orwell boy

From what I understand the second battery only runs the electronics in stop start mode, your better off not using stop start mode anyway all it does is fook your engine up

Yes i am 100% in agreement with you on not using stop start ,but my findings were without that battery working the hill hold function, when transfering your foot from brake to accelerator did not function .New battery non genuine now hill hold works even when stop start is switched off
Puzzled me !

[mick]

[QUOTE=Orwell boy;848350]

Originally Posted by mick

Yes i am 100% in agreement with you on not using stop start ,but my findings were without that battery working the hill hold function, when transfering your foot from brake to accelerator did not function .New battery non genuine now hill hold works even when stop start is switched off
Puzzled me !

Mine must of been doing a regen the other week as I was pulling up and dumped the excess fuel into the oil quick oil change needed