SOLVED - rear sonar beeps while towing

[green troll]

Hi guys well I finally fixed this. I have rear sonar but no switch. So I gather that mine is dealer fitted not factory. However, where the switch would normally be the wiring is actually there for the switch.

I could perhaps have ordered a switch from Mitsubishi but not sure the dealer sonar would turn off with factory wiring. Also I want to fit a AOB compressor switch in that location.

After ringing my dealer they wanted to charge me to fix this issue and said its not a warranty claim even though I argued that it wasn't installed properly.

So I set to it myself.

[green troll]

Ok first thing was to pry of the upper drivers side cargo area trim quite easy.

Then to get the bottom of there's a couple of screws. One near the rear and one near the 2nd row seats.

The cargo tie down point needs unbolted on that side too. It took awhile to figure it out but the centre bit is a cap so just pry it up and unbolt.

I think I also removed the rear trim at the back door. Ie the carpet trim. It's a few press studs you pry out inside the 3rd seat well.

Lastly unscrew the carpet retainer thing once you remove the 3rd seat well cover.

[green troll]

Ok now you can wriggle out the lower trim. Few press studs and a screw or two. Very easy to work out.

Next I took the cover of the tow plug just to check how it was hooked up. The reed switch is the two outer smaller grey wires. Turns out it's normally closed and one side is grounded to the body.

[green troll]

Ok photo time.

There's two boxes. One is the two controller and the other is RPA. (Rear parking assist I presume)

I then noticed the grey wire with a plug on it. It comes from the tow harness loom. Since I worked out the grey wires are a n/c grounded circuit I assumed it might switch the park assist on/off.

Then looking at the power for the RPA it gets its power feed from a fused reverse cct I believe. The ground goes through another plug then earthed at the body.

Here's the easy part.
Unplug the RPA earth single connector and plug it into the grey wire.

Bingo bango job done. Too easy.


First pic of the overall setup.

[green troll]

SOLVED - rear sonar beeps while towing

The grey reed switch ground



Next the plug with the original black earth to body connection and then connecting the RPA earth to the reed switch ground.

[green troll]

And I think I will mount those control boxes instead of them just flopping around.

[green troll]

Hope this helps others

[Hatto]

Nice one. I'm sure this will help others out one day

[likatiger]

Nice work, but to me, very scary - all those wires, switches & boxes, just leaves me cold and stressed.

[Steve879]

Yep, i did the same on mine. Easy job!

Steve

[jasper361]

Some great info there. I have the factory disable switch but the reed switch is not wired in. I'm hoping to have both working, I don't know why they don't wire up the reed switch from factory.

[OldEmmGee]

The reed switch (in the trailer socket) is meant to be connected to the RPA kit when it has a Genuine Accessory (Australia developed) kit; the Japanese developed 'Original Equipment' RPA system does not interface with the reed switch; Japanese rarely tow.

[Odie]

The reed switch (in the trailer socket) is meant to be connected to the RPA kit when it has a Genuine Accessory (Australia developed) kit; the Japanese developed 'Original Equipment' RPA system does not interface with the reed switch; Japanese rarely tow.

My tow bar was dealer fitted prior to delivery. Does the Japanese OE system hook up differently meaning this fix won't work for those with the Jap OE? I've had the right rear & floor panels out of the boot in the past and don't remember seeing either of those two modules in there (not that I was looking for them).

[green troll]

I would have thought it would work for both. All you doing is using the reed switch as the ground. So if it doesn't have the plugs then just cut n shut. Not really a interface in the true sense of the word. Your only messing with grounds so can't hurt to try. The RPA was Velcroed in behind the pane. Tucked away. Where as the tow ecu was just hanging around. So yours might both be neatly tucked away.

[kiwi horan]

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