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Just out of curiosity, will the factory radar cruise control do an emergency stop if its set to cruise and a car pulls out in front? Or is there only a certain percentage of braking forced which can be applied by the cruise control? I would be guessing the latter?

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https://www.sau.com.au/forums/topic/308786-m35-radar-cruise-control/
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Im not sure, can you test it for us? :) Wont it just roll off the throttle?

I do know the new volvo will do a full emergency stop, not sure its a good idea though. I always wondered what would happen if a bit of newspaper blew onto the road or a roo bounced past. Could cause problems for the car behind. :D

Im not sure, can you test it for us? :) Wont it just roll off the throttle?

I do know the new volvo will do a full emergency stop, not sure its a good idea though. I always wondered what would happen if a bit of newspaper blew onto the road or a roo bounced past. Could cause problems for the car behind. :D

Exactly my thoughts! I've read some where on here that the system does in fact use the brakes to slow the car if needed, but just not sure if it will do an emergency stop. Hmm... yeah will have to test it out when I get the car... but I'd say it would only be allowed to apply a small amount of braking force. Another question would be whether it uses the speed sensor and brakes when going down hills to maintain the correct speed. But I'm guessing if they've gone as far as to use a radar they would've implement that for sure...

Edited by Vesza

It would be a great package if that's the case. Shame about the obtrusive radar sticking out the front.

You could always put big wheels on to bump up your speed, if needed. 22 inch rims should do it. :D

Yeah the radar grille looks like barf!

haha, yeah or I may look into tampering with the speed sensor. Was just thinking to myself.... an even better option would be adding GPS guided cruise control. So when I'm driving to Melbourne I can do 150km/h and automatically slow down for the speed camera's at each bridge :D

one way to test is to setup a pile of cardboard boxes and then 'cruise' into them and see if it stops!

or foam, or something else soft. maybe a group of people?

Funeral gathering?

Saves time!

(didn't put in my first or second thoughts.... would probably have gotten a warning :ermm: )

Edited by iamhe77
  • 2 months later...

For those interested, the factory radar cruise can apply the brakes HARD if it feels the need (it has activated the ABS in mine before), and can slow the car down to around 5km/h or so. It might be able to stop completely, though I haven't been game enough to let it try.

If while driving you catch another car and the speed difference is too great, it will beep to indicate that another car is within the range of the radar, and either roll off the throttle or brake gently to maintain the safety gap distance you have set. If the speed difference isn't too high, it will just match speeds with the car in front without a beep.

The safety gaps are "far, very far, and stupid far"

It will only apply the brakes to maintain the set cruise speed if you are following another car, so on a steep downhill it will basically free roll. At 120km/h the cruise beeps and disengages.

Occasionally it will have a fit at some odd-angled road signs, when driving into morning/evening sunstrike, and it will sometimes 'see' oncoming traffic as being in your lane. Most of the time these events just produce a beep, as the object passes by and the radar clears. In some cases it will stamp on the brakes, though again only for a brief moment (though this is annoying for people following)

Fortunately in all cases it beeps which gives you time to react. Once you know what to look out for, you can predict it's behavior.

The brakes are activated by an actuator which actually pushes the brake pedal, it's creepy to feel it moving.

The cruise won't engage below 45km/h, or if the gearbox is in manual mode or snow mode, or if the windscreen wipers are on normal or fast. It also won't engage if the radar unit is obscured/disconnected.

It will disengage if the front wipers are turned on for more than 10 seconds or so (though it is happy to operate if the wipers are only on the intermittent setting). It will also disengage if the rear wheels slip, if the sensor becomes too dirty (following cattle trucks etc), if you corner too hard, or if the car aquaplanes. The cornering one I discovered playing on a track - you'd have to be *really* pushing on the road.

It must have a G or steering angle sensor somewhere also, as it will often allow the speed to drop while cornering, and then accelerate back to the set speed once the wheel is straight again. I guess this avoids ending up with a heap more power being applied mid-corner.

It's not without it's problems, but it's a damn clever system. Just a shame it can't be set over 110km/h - my speedo reads 10km/h low at 100km/h.

For those interested, the factory radar cruise can apply the brakes HARD if it feels the need (it has activated the ABS in mine before), and can slow the car down to around 5km/h or so. It might be able to stop completely, though I haven't been game enough to let it try.

If while driving you catch another car and the speed difference is too great, it will beep to indicate that another car is within the range of the radar, and either roll off the throttle or brake gently to maintain the safety gap distance you have set. If the speed difference isn't too high, it will just match speeds with the car in front without a beep.

The safety gaps are "far, very far, and stupid far"

It will only apply the brakes to maintain the set cruise speed if you are following another car, so on a steep downhill it will basically free roll. At 120km/h the cruise beeps and disengages.

Occasionally it will have a fit at some odd-angled road signs, when driving into morning/evening sunstrike, and it will sometimes 'see' oncoming traffic as being in your lane. Most of the time these events just produce a beep, as the object passes by and the radar clears. In some cases it will stamp on the brakes, though again only for a brief moment (though this is annoying for people following)

Fortunately in all cases it beeps which gives you time to react. Once you know what to look out for, you can predict it's behavior.

The brakes are activated by an actuator which actually pushes the brake pedal, it's creepy to feel it moving.

The cruise won't engage below 45km/h, or if the gearbox is in manual mode or snow mode, or if the windscreen wipers are on normal or fast. It also won't engage if the radar unit is obscured/disconnected.

It will disengage if the front wipers are turned on for more than 10 seconds or so (though it is happy to operate if the wipers are only on the intermittent setting). It will also disengage if the rear wheels slip, if the sensor becomes too dirty (following cattle trucks etc), if you corner too hard, or if the car aquaplanes. The cornering one I discovered playing on a track - you'd have to be *really* pushing on the road.

It must have a G or steering angle sensor somewhere also, as it will often allow the speed to drop while cornering, and then accelerate back to the set speed once the wheel is straight again. I guess this avoids ending up with a heap more power being applied mid-corner.

It's not without it's problems, but it's a damn clever system. Just a shame it can't be set over 110km/h - my speedo reads 10km/h low at 100km/h.

Yerp, discovered pretty much exactly what you wrote, about mine. Except haven't tried the hard cornering stuff. My speedo is also 10km out. Yeah the radar doesn't work too well when there's too much water spray following other cars, hence why it's designed to disengage if you set the wipers on anything else other than intermittent. I also get the same random blip of the brakes here and there (pretty rare though). As you said, would be nice if it could be set over 110km/h!

Also, depending on the vehicle shape and height, sometimes it won't detect the car until much closer than set... doesn't happen often, but still need to be on your toes. I haven't had it brake hard enough for the ABS to kick in, but I have a feeling once it got real close it would finally get a better radar bounce back and stop in time... just not game to test it lol.

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