Trailer Stability Assist

[rocket rod]

I have an MY16 D4 and tow a camper trailer and it's only 800kg unladen. When purchased I asked the dealer if LR had solved the trailer LED issues and he said yes. I left it at that. The trailer has LED lights and everything works correctly, no pulsing of lights etc. My question is how do I know TSA is working. There is no trailer icon on the dash when indicating and I know TSA does not require electrical connection. My trailer only has the plunger style cable brakes so I'm guessing TSA only works with the car's brakes & traction control. Perhaps the whole system is working but I can't tell. The trailer does not sway, so maybe it is? When should the trailer icon show on the screen? The trailer uses the black plug.

[Chops]

Interesting dilemma.
So, I was towing my camper (Forward Fold) and ran off the bitumen at a rather rough spot. Just pulled the car quietly back into the centre of my lane. I noted at the time how effortlessly it all happened,, just recovered from all that, and alas,, I managed to do the exact thing again.

So, I do believe it all works, and works well. Had I been in the Defender, the rough edge would have been noted very easily and I’d have felt it yanking at the wheel to pull me right off the bitumen.
No bells, whistles or lights came on telling me anything had happened though.

[Ferret]

My trailer only has the plunger style cable brakes so I'm guessing TSA only works with the car's brakes & traction control. Correct, it's similar to DSC.


When should the trailer icon show on the screen?
When the vehicle has detected a trailer has been hitched. If you get no trailer icon you still have TSA but you don't get the other adaptations like reverse sensors disabled, gear box shift points changed + whatever else is involved.

To get the vehicle to detect a trailer has been hitched you need to provide sufficient electrical resistance in the trailer's turn indicator circuits - ie fit load resistors in parallel to the indicator lights. Once this is done you will get the trailer icon on the dash.

[cjc_td5]

I have an MY16 D4 and tow a camper trailer and it's only 800kg unladen. When purchased I asked the dealer if LR had solved the trailer LED issues and he said yes. I left it at that. The trailer has LED lights and everything works correctly, no pulsing of lights etc. My question is how do I know TSA is working. There is no trailer icon on the dash when indicating and I know TSA does not require electrical connection. My trailer only has the plunger style cable brakes so I'm guessing TSA only works with the car's brakes & traction control. Perhaps the whole system is working but I can't tell. The trailer does not sway, so maybe it is? When should the trailer icon show on the screen? The trailer uses the black plug.Yes the D4 only sends a pulse to detect the trailer on startup and when the driver's door is opened (IIRC), not continually as the earlier D3 did. Therefore the pulsing issue has gone. If you have LED trailer lights the D4 may not detect any load though so trailer functions will not activate. The easiest way to fix this is to install a load resister into one of the indicator circuits on the trailer.

The easiest way to see if the trailer functions have been activated is the stick it in reverse. If the reversing sensors blare out hitting the trailer then it is not activated. If the sensors are deactivated then the D4 knows the trailer is there and all stability functions are active.

[DiscoMick]

Excuse my ignorance, but would a D4 also detect LED lights on a bullbar and activate for them?

[scarry]

Excuse my ignorance, but would a D4 also detect LED lights on a bullbar and activate for them?

On mine they are switched by relays,so no it won't detect them.

But then i don't know why it doesn't detect the relay coil?

On the D2 it used to detect them and the trailer in dash symbol used to come up.

My D4 has load resisters,which need to be turned on when needed,via a switch.

[Hugh Jars]

My MY16.5 does not sense a trailer with LEDs. Therefore, I can’t see how TSC could be activated if the car doesn’t know it’s there.
I made up the resistor pack with a switch to connect them when I’m towing.
Apparently you only need one resistor, but I’m a bit retentive and did both sides, so the trailer caption flashes with both indicators.

[Eric SDV6SE]

Excuse my ignorance, but would a D4 also detect LED lights on a bullbar and activate for them?

To my knowledge no, as the front factory turn signals are Incandescent there is already enough current draw

My BB lights are wired into the front L and R signals respectively, no issues with flicker or such.

Not sure why a bull bar would affect TSC though...

[Ferret]

Therefore, I can’t see how TSC could be activated if the car doesn’t know it’s there.

It's like DSC, depends only on how vehicle's steering, wheels and body are moving as a response to being pushed around by a trailer. It does not need to know a trailer is specifically hitched, it can feel it.

It can't use this to specifically detect a trailer is hitched because the vehicle is not pushed around by the trailer when the vehicle is stationary.

[DiscoJeffster]

Ferret, I think you missed a ‘not’ above.

Trailer Sway Assist is actually not really anything fancy. It is a byproduct of the standard stability control function which detects the vehicle yawing around the vehicle centre out of sync with the steering input.

It does NOT require the trailer to be sensed. There is a video posted on another threat which shows how it works.
The trailer being sensed allows for other functionality such as revised gearbox change ratios and minor suspension terrain assist adaptions etc.
The same indicator that would indicate stability control activation would also show if the trailer was causing it. It is via the ABS circuits to pulse the various brakes, manipulate the throttle etc. Stability control is no miracle cure, but if the traction exists underfoot then the stability control has some chance of saving you.

[rocket rod]

I'm glad everyone here confirms what I was thinking. The only component left out of my system is the load resistor, Narva have this one Narva |
12 VOLT 21 WATT L.E.D LOAD RESISTOR (https://www.narva.com.au/products/90034BL2)

That's the next job I guess.

[Redback]

Trailer Stability Assist

YouTube (https://www.youtube.com/watch?v=JyNjRq46lDs)

[rocket rod]

Trailer Stability Assist

YouTube (https://www.youtube.com/watch?v=JyNjRq46lDs)

Yep, seen that one.

[Redback]

Yep, seen that one.

Just trying to get the message across, it's something that doesn't seem to be sinking in with D4 owners.

Another thing, just turning the headlights on will solve the trailer LED issue, sure the trailer indicator on the dash doesn't work, is it that important.

[DiscoMick]

I only asked about LEDs in the bullbar because my Defender detects them in my ARB bullbar and the trailer symbol is always illuminated, so I wondered if D4s would be different.

[kelvo]

I only asked about LEDs in the bullbar because my Defender detects them in my ARB bullbar and the trailer symbol is always illuminated, so I wondered if D4s would be different.
Are you sure your bullbar indicators are actually LED?

On my D2 the ARB bullbar was supplied with normal incandescent globes for side and indicators, my D2 saw the additional current draw from the indicators and assumed I had a trailer so flashed the dash trailer icon.

I later upgraded the bullbar lights to ARB LED ones (The same type supplied with the D4 summit bullbar) and no longer had the trailer icon when indicating. Even with my camper trailer (With LED lights) attached to the D2 the current draw of two additional LED indicators (Per side) was still not enough to illuminate the dash trailer icon. The same is true with my D4 with summit bullbar and LEDs lights. Which is why I bought a pair of load resistors and a switch, the fitting of which is on my growing list of things to do...

[kelvo]

I'm glad everyone here confirms what I was thinking. The only component left out of my system is the load resistor, Narva have this one Narva |
12 VOLT 21 WATT L.E.D LOAD RESISTOR (https://www.narva.com.au/products/90034BL2)

That's the next job I guess.
I balked at the price of the Narva one so bought a pair from eBay at a fraction of the cost. I haven’t actually fitted them yet but have measured their resistance and it was 6.8 Ohm, within 5% anyway, which works out as 21W at 12V. I know a D4 is more likely to be at 14V but assume a normal 21W incandescent globe is rated at 12V, but I’ve never actually measured the resistance of one. They came from China, so probably made from Australia aluminium and copper [bigwhistle] and took 2 or 3 weeks to arrive 2x 25W LED 6.8Ohm Load Resistor For Hyper Flash Turn Signal LED Controlle HOT | eBay (https://www.ebay.com.au/itm/2x-25W-LED-6-8Ohm-Load-Resistor-For-Hyper-Flash-Turn-Signal-LED-Controlle-HOT-/192633839872'txnId=1588740612009)

[Eric SDV6SE]

Another thing, just turning the headlights on will solve the trailer LED issue, sure the trailer indicator on the dash doesn't work, is it that important.

dash trailer indicator works regardless of headlights on or off as it’s from the indicator, not the headlight or drl circuit, agreed the trailer stability control is active regardless

[Redback]

dash trailer indicator works regardless of headlights on or off as it’s from the indicator, not the headlight or drl circuit, agreed the trailer stability control is active regardless

Not on our D4, if I tow a trailer with LEDs and don't have the headlights on, the right indicator on the trailer won't work, soon as I turn the lights on it works but the trailer light on the dash stops working, for me it's not a big deal.

[wardy1]

Just looked at the eBay ones compared to Narva. The Narva site says they must be mounted to metal as they can reach 170c and will melt plastics, carpet etc. They have an aluminium heat sink for that reason. The Chinese ones are all plastic.
Comments from those who know more about all this stuff please

[wardy1]

We just did a trip to Dargo with our new Mars hybrid trailer. Obviously it has LED’s. The trailer assist DEFINITELY wasn’t working as we had very uncomfortable trailer sway on several occasions.
This is a ‘must fix’ before we go travelling in coming weeks

[cjc_td5]

Just looked at the eBay ones compared to Narva. The Narva site says they must be mounted to metal as they can reach 170c and will melt plastics, carpet etc. They have an aluminium heat sink for that reason. The Chinese ones are all plastic.
Comments from those who know more about all this stuff pleaseMine is a Narva load resistor and is mounted onto a metal bracket behind the trim in my D4. Remember though that mine is wired into a turn indicator circuit, so is active for very short periods (vs wired into a tail light circuit etc), so heat generation would be minimal.

[kelvo]

Just looked at the eBay ones compared to Narva. The Narva site says they must be mounted to metal as they can reach 170c and will melt plastics, carpet etc. They have an aluminium heat sink for that reason. The Chinese ones are all plastic.
Comments from those who know more about all this stuff please
The eBay ones I bought are definitely not plastic 2x 25W LED 6.8Ohm Load Resistor For Hyper Turn Signal LED Controlle HOT | eBay (https://www.ebay.com.au/itm/2x-25W-LED-6-8Ohm-Load-Resistor-For-Hyper-Flash-Turn-Signal-LED-Controlle-HOT-/192633839872'txnId=1588740612009)

Yes they get hot when the indicators are being used, but no hotter than a normal 21w incandescent globe.

[wardy1]

Thanks Kelvo. I did take a closer look at your link and yeah..... my mistake[emoji5]

[weeds]

We just did a trip to Dargo with our new Mars hybrid trailer. Obviously it has LED’s. The trailer assist DEFINITELY wasn’t working as we had very uncomfortable trailer sway on several occasions.
This is a ‘must fix’ before we go travelling in coming weeks

Just wondering what your weights are and the distribution.......to have uncomfortable trailer sway.

[rocket rod]

Thanks for your responses on this issue. I'm now the proud owner of 2 Chinese metal load resistors ($15) that are yet to be installed. What I would like to know from someone is what method they used to install one in the car (instead of the trailer) so they can be used on any trailer eg hire units. My guess is there would need to be a switch to turn them on/off so TSA is not active full time?

[DiscoJeffster]

Thanks for your responses on this issue. I'm now the proud owner of 2 Chinese metal load resistors ($15) that are yet to be installed. What I would like to know from someone is what method they used to install one in the car (instead of the trailer) so they can be used on any trailer eg hire units. My guess is there would need to be a switch to turn them on/off so TSA is not active full time?

Yes, many install it and make it switchable with a switch in the boot area. Wire it across the indicators as you would on the trailer. You’ll want a double pole switch to maintain separation of each indicator circuit, assuming you put one on the left and right side.

[rocket rod]

Yes, many install it and make it switchable with a switch in the boot area. Wire it across the indicators as you would on the trailer. You’ll want a double pole switch to maintain separation of each indicator circuit, assuming you put one on the left and right side. Do you have to put one on each indicator (I couldn't be bothered frankly)?

[wardy1]

Just wondering what your weights are and the distribution.......to have uncomfortable trailer sway.

Went over a weighbridge on the way home actually.
Trailer was 2250kg (with gas bottles and 1 of 2 100ltr water tanks full). The car came in at 3320kg so gross was 5570kg. Well within the limits according to the handbook.

[weeds]

Went over a weighbridge on the way home actually.
Trailer was 2250kg (with gas bottles and 1 of 2 100ltr water tanks full). The car came in at 3320kg so gross was 5570kg. Well within the limits according to the handbook.

Cheers...I tow 2T trailer regularly with a POS hi-lux and never get the wobbles. I don’t tow over 2T often.....

I had a quick look at the website, the standard spec, if this indeed yours is

2000 Tare
2400 ATM
180 TBW

Wouldn’t have thought this would have bothered a disco

[DiscoJeffster]

Do you have to put one on each indicator (I couldn't be bothered frankly)?

Supposedly not though for completeness I did. When you indicate, the trailer light on the dash flashes and is another indicator the trailer is detected. With only one side, you won’t see the flash on the non-modified side. It doesn’t matter, it’s still detected, just whether you’re a pedant like me or not and want the indicator for both sides.

[kelvo]

Went over a weighbridge on the way home actually.
Trailer was 2250kg (with gas bottles and 1 of 2 100ltr water tanks full). The car came in at 3320kg so gross was 5570kg. Well within the limits according to the handbook.
Which water tank was full front or rear? If it was the rear that would most likely be the reason for the swaying, the heavy rear will act like a pendulum keeping the sway going.

[LRD414]

... The trailer assist DEFINITELY wasn’t working as we had very uncomfortable trailer sway on several occasions.
Did the vehicle change behaviour to correct the sway or did you intervene? I’ve never felt it operate but understand it to be very subtle.

Scott

[wardy1]

I had to either slow down or apply the electric brakes manually

[cjc_td5]

Do you have to put one on each indicator (I couldn't be bothered frankly)?

No. Only one side is required.

[Redback]

Thanks for your responses on this issue. I'm now the proud owner of 2 Chinese metal load resistors ($15) that are yet to be installed. What I would like to know from someone is what method they used to install one in the car (instead of the trailer) so they can be used on any trailer eg hire units. My guess is there would need to be a switch to turn them on/off so TSA is not active full time?

TSA is on all the time as it's mechanical, so can't be turned off or on, it works by sensing trailer sway.

[rocket rod]

Sorry to bring this old thread up again but I've installed the load resistor onto the RHS car indicator using a switch in the circuit. I've checked the wiring job with a test lamp and that flashes in unison with the indicators (and doesn't when I flick the switch) but I don't get any trailer icon on the dash. Do I have to have a trailer attached to make it happen or should the dash icon flash without a trailer?

[disco4now]

I've installed the load resistor onto the RHS car indicator

The car indicators are on a separate circuit to the trailer indicators. The load resistor will need to be in parallel with the trailer indicator. You could put it in the car, but it needs to be from the trailer indicator circuit to earth. If switched on it should indicate a trailer attached even when its not there.

regards
Gerry

[rocket rod]

The car indicators are on a separate circuit to the trailer indicators. The load resistor will need to be in parallel with the trailer indicator. You could put it in the car, but it needs to be from the trailer indicator circuit to earth. If switched on it should indicate a trailer attached even when its not there.

regards
Gerry

Damn, I thought that might be the case. Thanks