Thread: Reversing Alarm Issue When Towing

Sounds like you have LED lights on the trailer. With the D4 you will need a pulse buster or similar to induce enough load on the indicator circuit to sense the trailer.

Going to take a guess, and suggest you have LED's on your trailer.

They do not produce enough resistance for the car to recognise it is plugged in.

I am fairly sure the dealers are aware of this, and have a fix. If not, then you can get a special loading resistor from places like Repco & the like.

Originally Posted by Basil135

Going to take a guess, and suggest you have LED's on your trailer.

They do not produce enough resistance for the car to recognise it is plugged in.

I am fairly sure the dealers are aware of this, and have a fix. If not, then you can get a special loading resistor from places like Repco & the like.

Correct I do have LED lights. In fact on my cool room trailer LED lights intermittantly blink when connected to the D3.

Cheers for the advice. I shall visit repco this afternoon!

Cheers,
James

There is a long post on this on the forum. I bought a resistor from Repco for about $14 from memory.

The flashing is the CAN BUS running a light current through the blinkers and measuring the resultant voltage drop to see if there is a trailer connected.

If it does detect one,
-the automatic transmission "trailer" program is engaged
-trailer stability control is engaged
-rear park assist is disengaged
-some other stuff I can't remember

As the others have said, there's numerous ways you can get around it. I would personally just solder a resistor to match an incandescent bulb in line with the LEDs and see if that works.

You also have a button on the dash with something like P>>> on it and a light. Push that and it turns rear park assist off.

Originally Posted by Rich84

The flashing is the CAN BUS running a light current through the blinkers and measuring the resultant voltage drop to see if there is a trailer connected.

If it does detect one,
-the automatic transmission "trailer" program is engaged
-trailer stability control is engaged
-rear park assist is disengaged
-some other stuff I can't remember

As the others have said, there's numerous ways you can get around it. I would personally just solder a resistor to match an incandescent bulb in line with the LEDs and see if that works.

You also have a button on the dash with something like P>>> on it and a light. Push that and it turns rear park assist off.

Ok so last night I put a resistor inline on the number plate light. It got hot so was working but the car still did not recognise the trailer.

It is a standard Narva 12 v 21 watt LED Load Resistor. I am going to pick up another one this afternoon and hopefully that will solve the problem...

Does anyone know if you require 2 or more. Dont want to go installing multiple resistors if they are not required.

Cheers,
James

I should think if you either wire one in line with each of the blinkers, or in line on the common earth, it would work.

CAN BUS tests through the blinkers, that's why they flash and not the brake or tails.

Originally Posted by jwb300

Ok so last night I put a resistor inline on the number plate light. It got hot so was working but the car still did not recognise the trailer.

The resistor needs to be wired in 'parallel' with the blinker light, not 'in line' with the number plate light or any other light. You can wire both left and right side if you want to but only one resistor on one side is actually required.