Hi, can anyone advise ?

I'm wiring up PIAA driving lamps - I've put a relay between the original fog lamp + loom and the battery earth - this will give a switch signal from the fog lamp switch.

I was going to take a wire from the connection on the headlamps (I've fitted HIDS, so the headlamp bulb connector is loose) for MAIN beam, through the switched side of the above relay, to the switching side of the PIAA relay. The other side of the PIAA relay goes to earth.

Therefore, the fog lamp switch AND the main beam must be on to activate the PIAAs. NB: The power for the PIAA bulbs will be from the battery to the battery, via the bulbs and the switched side of the PIAA relay.

THE PROBLEM:

I've put a volt meter between the terminals (each in turn) of the headlamp plug and the - side of the battery- I can't work out which is the main beam - The top connection (horizontal) gives about 0.4 volts when main beam is on - The others are not effected by main beam selection.....

Mark

Classic or new age?
Alcazar

Sorry matey ---

Its a 98 UK turbo- The other complication is that I've just fitted the HIDS, so the Drivers side headlamp connector (the 3 pin rubber jobby) is connected to the HID system, where its used to indicate to the HIDs whether DIP/Main is on.

I'm hoping to use the passengers connector, as its just dangling free ...

Mark

Well, shouldn't be a prob.
Can you see which of the driver's side connections actually attaches to the main beam? Does it go to a relay, or to the ballast direct?

In fact, you could tap into either of those wires, (to a relay, or direct to ballast from that connector), to get the wire you want.

Alternatively, use a circuit tester: mine is like a screwdriver with a wire coming out of the handle, and a 12V bulb in the handle, about £2 from car shops. Attach the wire to earth, battery -ve is best, then onto each of the connections in the connector behind the o/s lights, with main beam selected, and ignition on, obviously:D:, and whichever causes it to light up is the wire you want.

Hope this helps.

Alcazar

BTW: if you're TOTALLY stuck, let me know, and I'll go and try and see which one it's from on my '98, it's not easy to see, as the air horns are in the way!

A

Cheers,

I've looked (last night) at the N/S, as its free - I thought I'd use spade connectors to plumb straight in.

Rather than a digital indicator, like an electrical screwdriver, I used a multimeter (on 0-20v DC range), but I can't understand the odd voltage result,

unless the HID kit is somehow drawing the power and the voltage is off, due to a lack of load - but I reckon this is tosh !

I'll take another look tonight, maybe by measuring between the gnd and main beam connections, rather than the '-' post of the battery, in case I'm introducing some 'additional' circuit with the tester.

If I can't get any joy, I'll try the voltage on the O/S, as this MUST be working (HIDS are switching to MAIN beam on it...)

Thanks for your help, and I'll keep you posted, in case I need to take you up on the offer...

Mark

PS _ So as far as you know, its the + thats switched, NOT like the knocklink where the common is + (due to the chip) ?

[Edited by markwild - 1/14/2004 1:47:59 PM]

Yor voltmeter is supposed to read ACROSS, (in parallel with) a component, so I doubt it will read true voltage on it's own.
If simply placed in line,(series), as you have done, very little voltage will be indicated, as there is no component to push a current through, (only the meter, which carries mA, hence the low indication).

This is why I prefer a circuit tester, rather than a meter.

Why not TRY the connector giving 0.4V, as the worst you can do is blow it's fuse?
And if it's wrong, pull the spade out, and try another.

At least you have an indication that it's "LIVE" at the right time.

Alcazar

True - The only reason I'm confused at the reading is that the dip connection show 12v or 0v, depending on the switch position.

Anyhow, I'll try connecting the relay tonight (have to mount it to the car first) and see how I go on, as (as you say) I'm fairly sure thats the correct connection, as its the only one that reacts to main on/off :D

Cheers,

Mark

HMMM - OK, job done - the reason for the struggle is that the connection for the Main and DIP are switched EARTH, with common as 12v+.

Therefore, I can't take a + feed from the main beam connector to the relay and then ground the other side, as there isn't one !

I've wired the relay between the common and main beam connectors on the headlamp socket instead, which supplies a circuit, rather than just 12v.

Thanks for the assistance,

Mark