Thread: DSC towing problem

Originally Posted by BrianElloy

Does the trailer dash light illuminate when you indicate?

Reason why I ask, is that of not then the car is not recognizing the trailer probably because of LED lights not providing enough resistance

This will prevent the car from going into tow mode which affects DSC, gearbox shift patterns etc.

You’ll need one of these (or equivalent) to remedy

LED Tow Connect - Tow LED Fitted Trailers Safely: Discovery 4

hi brian do not have the trailer light on dash and i have noticed that when the caravan is hooked up and the lights turned on the blinkers flash on and off at a rapid rate and not very bright turn the lights off every thing is ok so i am tending to nagree with you about the tow connect any ideas on where to get a reasonably cheap one cheers pamax

Blinkers flashing fast and dull with the lights turned on is not a symptom that the car is not recognising the trailer. There is something wrong with the wiring if that is the case. It may have a poor earth or you may be sending your tail light signal to the brakes on the caravan if you haven't specifically wired it for the D4 as per other posts on the forum.

The D4 won't recognize the trailer if you have LED lights because the current draw is too low, not too high. Dull lights and fast flashing means the current draw is too high. The fix for LED lights is to wire a 21W resister into the indicator light circuits on the trailer, which is very cheap. You don't need a pulse shunt module. That is only required for a D3, whatever the add says.

I agree with Bob. Something not right there ..

Need to resolve that first before you get an LED module

Does a D3 cutout from overboost?

Originally Posted by pamax

have a disco 3 2007 tdv6se with air suspension and i tow a 2.6 tonne 20ft caravan no problems on the highway but as soon as i hit a hilly winding road the dsc light starts flashing especially when coming downhill around tight corners the warning light flashs and then goes out every thing is normal but i have had the system break down completely twice once when towing up a rather long steep hill got three parts the way up and all the bells and whistles came on no suspension, transmission fault have had the auto box serviced since. the second time it happened i jumped on the brakes when traveling at around 50kph and the same thing came in only happens when towing have tried all sorts of speed and corners without the van no problems have no trouble rectifying the problem so far simply turn the vehicle off leave for a couple of minutes and the computer resets itself and away i go has anyone had this happen to them do i have to replace the air bag suspension being a newby to land rover i was impressed to stsrt with now beginning to wonder

HI all thank you for your replies and advice fitted a tow connect to the caravan now the trailer light flashs with the blinker but when i turn on the headlights the blinkers pulseate without turning them on the same thing happens when the brake lights are applied i have hooked the van up to another tow vehicle and no problems so have looked at the earth on the car unless there is more than one i have hit a dead end i have thought of replacing the leds on the caravan but the clearance lights make this difficult the leds look as if they are a sealed unit and stuck on the caravan any suggestions cheers pamax

Is your Tow Connect for a Discovery 3?

Originally Posted by Graeme

Is your Tow Connect for a Discovery 3?

And is the trailer brake controller in your car correctly wired in accordance with the sticky on the forum? It is not the same as other cars so if the trailer lights work on another car it is likely that your D3 trailer brake controller is not correctly wired. If wrong, the trailer brake will be connected to the car tail lights and turning on the headlights will operate the brakes on the trailer.

Since both brake lights and headlights are not working correctly there is a high probability that the brake controller wiring is incorrect for a D3.

By the way, the advice was NOT to fit the tow connect until the wiring was sorted out because the LED lights were not the cause of your problem.

Originally Posted by Graeme

Is your Tow Connect for a Discovery 3?

yes graeme the paper work says it is the trailer lights on the dash works with the blinkers have checked plugs cant get into lights to check them but if the system works on another vehicle with no problems i feel it could be the d3 will check the brake controller but it seems ok with it all working