What's this switch for?

[gargravarr]

Hi all,

I fitted some plasma dials a few days ago (look pretty swish all lit up!) and it reminded me there's a flick-switch on the lower driver's dash panel that I have no idea what it does. It looks like a factory-fitted switch from the place it's mounted, but it's wired in with thin white wires that take positive straight from the battery (through the firewall) and then disappear deep into the engine. We've never switched it on, but when I was putting the dash back together, I noticed that connecting the cables to normally-closed caused a relay in the engine bay to flip (distinct sound), with the ignition off. I'm not sure if the switch was originally wired normally-open or normally-closed, but I reconnected it N-O and the truck's been fine.
Can anyone hazard a guess at what this could be connected to? I know there's a lot of aftermarket stuff that could have been fitted to the truck, but given that it's something we haven't explicitly used, and something that seems to have no visual feedback, I'm really stumped. It's not the rear foglight, as the switch for that is elsewhere, and the front foglights I fitted myself to another switch.
I know it's a long shot, but any guesses? I can take some photos if it'll help.
Cheers,
Gargravarr

[Albannach]

Photos of the switch and relay would help a fair bit.

[gargravarr]

I figured they might, I thought my mum was heading out when I posted the thread, but she's still here so I managed to get the photos.

Warning - 6 megapixel photos ahoy!

The switch is directly below the ignition, in a recess that looks like a spot for a factory-fitted switch.


I'm pretty sure the relay in question is this big one here, marked PIAA, mounted on the same post as the starter relay. The small one with the colourful wires connected is for the front foglights.

All the white wiring visible above seems to be related.

Cheers,
Gargravarr

[Overland Tonka]

PIAA are spot lights...any wires behind your grille?

[gargravarr]

PIAA are spot lights...any wires behind your grille?

Well spotted. I noticed myself that the relay said 'Professional Systems' and did a Google search, turning up the headlight company. I'll have a look when my mum comes home.

I'll be annoyed if there are cables there for spotlights as fitting the Ring Microline units was ****ing irritating!!

[Rob5464]

You thought they were annoying?

You wouldn't like to do mine then, I have two ring spots on the back as reverse lamps, 5 spots on the roof, two sets on the bull bars and some LEDS under the sills (for being able to see how much clearance I have before anyone thinks its Fast and Furious inspired.) Then I have to wire the indicators into the sidelights.

I have all the wires to channel through the car plus a switch board I am going to do the lot together so I don't have to keep dismantling the dash.

[gargravarr]

You thought they were annoying?

You wouldn't like to do mine then, I have two ring spots on the back as reverse lamps, 5 spots on the roof, two sets on the bull bars and some LEDS under the sills (for being able to see how much clearance I have before anyone thinks its Fast and Furious inspired.) Then I have to wire the indicators into the sidelights.

I have all the wires to channel through the car plus a switch board I am going to do the lot together so I don't have to keep dismantling the dash.

You might want to be careful driving near RAF bases, they might mistake you for a UFO at night

[gargravarr]

Mystery solved. The switch was for an old set of PIAA spotlights that were removed from the truck before we bought it. It neatly answered a question about some black blocks I found zip-tied to the air-conditioning radiator - I thought they were some kind of temperature sensors, but were in fact the taped-up connectors to the spotlights!

So, I removed the old relay, and managed to reuse the nicer cables from the PIAA set and rewire the current Ring set - I used a lot of cable bridges when installing them, including inside one of the lamp housings to power the other. And wouldn't you know it, the bridge melted due to heat and shorted the lead to ground - oops! Rewired with the PIAA cables and split the power to the lamps in the engine bay instead. Stupid Ring, not giving me nearly enough cable in the fitting kit!

[Wolfracer]

Glad you got it............................ .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .........sorted.
annoying aint it.
Try resizing your pics!

[gargravarr]

Sorry! Point taken, though I did stick in a warning!