Stuck in Park, no brake lights. High risk if towing.

[JLA]

D40 STX550 120,000klm.
Went to the tip today, just about to reverse in my trailer and found the gear selector was stuck in Park. I was able to use the manual unlock. Arrived home and checked this forum, I found a few faults the same, three were the Park switch and one I think was the brake fuse. I expected to find a blown fuse caused by a trailer fault but not so.

I checked the brake fuse - ok, but also noticed the brake lights were not working. Checked the brake light switch, the contacts were all open regardless of the switch position. Applied a light spray of WD40 with no change. Dismantled the switch, cleaned contacts, works fine. Will replace both the brake and the cruise switches tomorrow.

I had not considered before how dangerous the sudden failure of the switch is. I had just come down the Mapleton range with a full load of old sleepers in a four wheel braked trailer. If that switch had of failed a bit earlier, when I was going down the range, I would have been toast. That range often has accidents especially when damp. Without that switch working I have zero trailer braking.

These switches seem to be the same style for all Navaras, I would suggest if you are towing anything, especially a van, that both these switches get replaced to a preventive maintenance schedule. 100,000klm may be too far apart. It probably depends on luck and how often you press the brake pedals. I’ll be replacing mine every 80,000 in the future.

note: there are two switches on the brake pedal, one for the brake light (white connector, four wires) and one for the cruise control (orange connector, two wires). The switch assemblies just twist 45deg to remove, and press an indent to unplug. Easy job. In an emergency the brake switch could be repaired on the side of the road by carefully dismantling it and cleaning the contacts, but obviously it won’t last. It at least confirms where the problem is. Don’t forget to depress the brake pedal before installing the switch.

I found this informative YouTube url of emergency repairing the switch:
You can click on watch it on YouTube.

 

[Old.Tony]

Good advice, brakes are probably the most important tool you have when towing.

I did dismantle my switch and clean it, having had a similar problem myself. It's been good for a considerable time since - I hadn't considered a need to replace it, with over 300,000km on the car before I experienced any trouble with it (and it was only dirty, no wear issues).

I often (when towing, and descending a steep hill) manually apply the trailer brakes with my brake controller. I have a Tekonsha Prodigy P3, which has a lever underneath that allows me to apply a varying amount of braking force. I previously had a Tekonsha Voyager braking unit, which has a slide switch on the front (allowing for gradual braking) and this is the unit that's visible in my garage, which has been replaced (and I've added the breakaway battery monitor above it).

As a general rule though, if I come to a hill where there's a sign indicating "Trucks And Buses Must Use Low Gear", or it if looks steep enough, I'll drop a gear (or more) and my speed (and let other vehicles past) so that I have less issues with everything. Coming down Bells Line at Kurrajong is particularly irksome because of the hairpin bend, and descending Thunderbolts Way is always an issue with its several-kilometre descents at around 12%. One of those steep sections has 45km/h corner at the bottom - I have no idea why they'd do something like that!

 

[JLA]

I also had a Tekonsha braking unit with the slide switch at front and it was the best one I ever had. It allowed full manual control while driving without disturbing the brake setting.

Currently I have a Redarc. It has one rotary knob that does everything, even change mode. This controller has been a disappointment, but most reports say how wonderful it is?

Many people imagine that if their trailer brakes fail then the tow will be able to stop the combination. Hopefully that would be the case, but if at max load or steep incline, any dampness then probably not even at slow speeds. It is very scary when you apply full brake pedal and nothing happens. A bend in the road, can’t keep pressure on there. It’s not just the brake switch, the trailer connector is a weak point as well. I have a good solution though, grow grey hair, put a hat on to look like a farmer and crawl along. People accept that.

The brake switch looks like it has two contacts but it really has four. There are two that get dirty and two that stay cleaner. The video focuses on the two that get dirty. The dirty contacts on mine were difficult to clean as the plating was affected and partly pitted. I thought about adding a relay but that is also another failure point and non standard.

When I look at the fuse/relay boxes I can see references to a tow relay. If there was such a thing it would reduce the current for the brake switch. I know my trailer plug comes off the vehicle brake lights, but perhaps it should come off a tow relay? Has the trailer plug been wired incorrectly and overloading the switch?

Because I live at the top of a range I use my brakes a lot, perhaps that’s why I am experiencing premature wear of the brake switch?

 

[Old.Tony]

I would have thought that city traffic would cause more issues, so tradies would have had a problem ages before us!

There might be something in the brake light circuit (which includes the trailer lights) that's causing an issue, particularly if the electric brake controller is drawing too much power through the circuit and the switch contacts (causing that pitting you've noticed - I didn't have that in mine). My caravan has LED tail lights, maybe that's part of it? The brake controller shouldn't draw a lot of power through the brake light circuit, it should only use that as a trigger.

Redarc has a steady following here in Australia because it's a local company, but I don't particularly like their brake controllers. I had one in my Commodore wagon many years ago, and it was difficult to use, whereas my Tekonsha devices are much easier and better. The Prodigy was better than the Voyager for a couple of reasons - apart from the display, the P3 allows installation on an angle and the Hall-effect sensor inside still works to detect braking motion (which is how they work). The Voyager wasn't as flexible.

 

[JLA]

The trailer uses leds so should be moderate current. Perhaps some manufacturing contamination inside the switch started the arcing/corrosion process early.
Nissan don’t stock the stop switch in Australia, it’s 2 - 3 months delivery from Japan. Burton’s stock them though. Not sure if the part numbers are for all D40’s or just the STX550? Can’t imagine why they would be different.
Nissan. 253003ARA0A. $58.00
Bursons. SLS-067

I did not try for the cruise control switch, I think. I’ll let it go as it works.