Thread: D4 Trailer Lamp Not Illuminating.

Howdy Jack,

The new Jayco must present less load (on the trailer indicator circuits) to the D4 then the previous trailer. Did the previous trailer have globes... and the new LED?
When the drivers door closes the D4 sends a pulse out the indicator circuits to detect if a trailer is there. This requires sufficient load for detection to correctly identify the trailer. Trailers with modern LED lights do not provide sufficient load.

"Advanced Search" for "NARVA 21W" in the top right corner... you will find many posts on the issue... and various different methods of solving the issue.

Regards,
Gordon

Hi Gordon,
both had the standard Jayco tail & marker LED lamps, only difference between the vans is the ALKO ESC,

thanks
Jack

Don't dismiss the diagnosis because of them both being Jaycos with leds.
What has been stated is correct. It may be that the ESC is in series with the indicator circuit and is high resistance (i doubt it though) but the answer is still to put a low resistance load in parallel with at least one of the indicator circuits.

Hi Guys,

I'm hiring a Jayco Expanda Tourer to go to Mt Moffat/Carnarvon Gorge in a few weeks time. It has LEDs, so I suppose I could have the same issues discussed in a multitude of threads.


Reversing the question maybe .... Since I don't own the van I can't modify it. Is it safe to drive with all aspects of the circuitry not fully active?


Cheers,


Kev.

It'll be fine to drive as long as the lights are working. You'll be driven mad by the reversing beepers when backing up, and the gearbox shift points won't be optimised for towing, but nothing too dramatic.

Personally, i've created a plug adapter with one Narva LED resistor running from an indicator circuit to ground. Cheap, works perfectly, and allows me to tow any trailer - i just keep it in the car.

Originally Posted by Celtoid

.... Since I don't own the van I can't modify it. Is it safe to drive with all aspects of the circuitry not fully active?

How heavy is it Kev? What about electric brake connection?

As mentioned lights will work but gearbox mapping not optimised, so making up an adapter is a good option but if not keen on that you can purchase one.
This may be useful if planning on hiring a van semi-regularly.
Linear Electronic Design | Buy Now

Cheers,
Scott

As mentioned, if you hire and don't purchase, consider making your own adapter box. But a couple of the Narva resistors, put them into a metal box (Jaycar), put a connector on each end and job done. With a tiny bit of soldering, some epoxy (water tight), for $60 you'll have your own adapter box. I added resistors to my trailer, however I also made a box for when I hire a trailer using some cheap 10W resistors in parallel in a box. Covered it all in epoxy to make it vibration proof and Bob's your uncle. Got me from QLD to WA without issue. Alternatively pay a couple of hundred for someone to make one for you.

Originally Posted by LRD414

How heavy is it Kev? What about electric brake connection?

As mentioned lights will work but gearbox mapping not optimised, so making up an adapter is a good option but if not keen on that you can purchase one.
This may be useful if planning on hiring a van semi-regularly.
Linear Electronic Design | Buy Now

Cheers,
Scott

Hi Scott,

According to the website its Tare is 1820KG .... 2304KG fully loaded (ATM). They say the van has electric brakes and they "hire portable EBC for vehicles that don't have one fitted".

I never tow anything other than a standard box trailer, so it's all gobbledygook to me :-).

I'll take a look at the load unit.

Thanks Scott.

Kev.