I've been wiring up the Smart this weekend. I'm fitting a Sony HeadUnit, the empeg, a PDA cradle and a Nokia Bluetooth Handsfree kit.

I'm really worried about running this much gear off my Ignition, does anybody have any experience with this???

I was thinking or wiring in a relay, but I'm not sure how to do this, anybody got any advice???

Cheers

Cris.

Have you put a DC ammeter in-line with the iginition sense line to check the amperage you're using when everything's powered on? So long as you're less than the fuse that controls the line you should be OK. You could also check for voltage sag when things are turned on (indicating a resistance upstream or in the wiring). Low voltage may be a bigger problem than popping fuses, depending on your car's wiring.

Of course I'm assuming you have also got the Sony head unit wired to permanent power as well as the ignition sense line, no (ie the ignition sense line is only used to tell the Sony when the car is on - not used to drive its amplifiers)?

Of course a relay would work as well, but they do take up space, which may be at a premium inside your dash. I'd check to make sure you really need one. I used one to cure the old power off thump issue (before the diodes on the empeg harness).

HTH.

-Zeke

Put a relay on the ign sence line and use the relay to switch power to your add'ons.

What sort of relay would I have to use??? Would any old 12v one do?

I'm assuming I wouldn't need anything other than the relay in the circuit, just the relay wired straight to my ignition on one side and the 12v supply from the battery on the other.

Cheers

Cris

Pretty much an old 12V relay from an autoparts store would be fine.

you have the ign wire trip the relay

use bosch relay # 0.332.015.013
wire pin 85 to good earth
pin 86 to ignition +12
pin 30 to battery+ (add a fuse here, 15 amps)
pin 87 outbound to power your stuff.
pin 87b is the same as 87

Where to get +12V though?

I've done it a dozen ways myself, but not sure what is available on this car or quite how to describe the process. My normal method is to attach a new wire right to the + terminal on the battery, with a new terminal actually, fuse it right next to the battery itself, and then run it through a convenient hole in the firewall and into the dash.

I don't have this problem with the Smart, the battery is under the floor on the passenger side, so about .5m of cable and an inline fuse will give my my 12v and a Ground straight off the battery terminals without making holes in the car

I really do love this car, now it's run in a little more it really goes some too. Can't wait to get the empeg in it, the Karma is not so good for use while driving.

Cheers

Cris.

"then run it through a convenient hole in the firewall and into the dash."

That's funny, I can only ever seem to find incovenient holes in my firewall.

Oh well!

-Zeke

That's funny, I can only ever seem to find incovenient holes in my firewall.

Are you just naturally amusing, or is it a program I can buy?

As a man who uses 5 relays (that's what my Range Rover Empeg set up ended up with), when one semi conductor would do, I hope I'm not being controversial in saying: I question that you need a relay at all if the accessories, HU and Empeg are correctly fused on the lead from the battery.

I'm more worried about burning out the ignition because I've got so much stuff running through it.

I was plagued by annoying ground loop and altenator noise on the last install, I figured this way it would remove any nasties already present.

I think I'm overkilling it alittle, but it's quite fun really.

Cheers

Cris.

I'm more worried about burning out the ignition because I've got so much stuff running through it

I'm not suggesting running it all through the ignition, I think that might be problematic, but taking a lead direct from the battery and putting fuses in line to the two HU's, all you'll be taking through the ignition is the ignition sensor leads and, possibly the bluetooth and the other gizmo.

I'll be running a straight 12v supply from the battery for the headunit and empeg as well as the relay on the ignition for all the ignition sense circuits.

I hope with good weather holds!!!

Cheers

Cris.