Wiring Diagram for headlamp relays using Porsche parts

[pete917]

Has anyone got a Suco relay (high beam) ugrade wiring diagram. I plan to do a twin relay upgrade but using the OEM IB relay and the wiring diagram would be very helpful.

 

Many thanks

[jevvy]

Has anyone got a Suco relay (high beam) ugrade wiring diagram. I plan to do a twin relay upgrade but using the OEM IB relay and the wiring diagram would be very helpful.Many thanks

 

Bentley manual is what you need - mines at home so cant help right now sorry. (not so useful for this Q but good for your other one)

 

You can pick them up cheap and they are well handy

 

A search on pelican might fetch up what you need too.

Edited July 2, 2007 by jevvy

[pete917]

thanks for that. Will look into getting one of those!

[johndglynn]

This is IanC's diagram for stock relays on H4s:

 

[pete917]

youre the MAN John - thanks.

 

I have ordered the OEM relays and sockets and so will report back on the job later!

[johndglynn]

I have ordered the OEM relays and sockets and so will report back on the job later!

I think I will swap mine out for the originals also, tidier job IMO.

[pete917]

I agree John. Ill let you know prices for the relays and part numbers as well as any other useful stuff for IB.

[stevecwalters]

I agree John. Ill let you know prices for the relays and part numbers as well as any other useful stuff for IB.

 

 

I am following this one as well, so you have an audience Pete!

[johndglynn]

Who was it on here that did the upgrade using Porsche relays, can't remember, was it Rainer? I will have a look. Anyway it is the way to go, just Sucro makes it so easy for £14 plus the P&P.

[pete917]

Ive got the pricing for the OEM relays - £15 each. Im waiting on pricing for the sockets, but im guessing they will be similar. Even though the price is going to be somewhere between £50-£60 (not including wiring and fuses etc) I do think it will look the part.

 

Im definitely going ahead with it....so will keep you all upto date.

[pete917]

a quick question - can any tell me the Watt rating for headlights and main beam for a standard H4 bulb. Also, when you switch to main beam, the dipped element goes out? Is that correct.

 

I want to work out the current flow around the circuit so I can rate bthew wire guages and fuses correctly.

[tea boy]

Porsche relay sockets, part no 901.612.333.00

I think they are about £30 apiece.

[pete917]

thanks. Ive ordered everything, should be with me early next week. Still dont know a price for the socket. The relay was £15, so £30 for both is probably about right!

[pete917]

OK, so here goes. Ive put together a drawing of my stock wiring configuration:

 

And here's what I am going to do to add seperate relays for both low beam and high beam. Ill keep the existing fuses so I have protection for each bulb load on the system. Ill also have one main fuse to protect the combined load on the new power supply. Next job is to calculate the fuse sizes and wire gauge sizes to take the load. If someone could tell me the wattage of the low beam and high beam I can make the calculation. Also, can someone say if the high beam and low beam are ever on together?

[Jean Berk]

Possibly when you flash your headlights they are on together - I think they are, although very briefly. Shouldn't cause any real issues if they do.

[pete917]

Thanks Jean - does anyone know what the wattage is for a H4 low and meain beam. I can work out the current drain on the various parts of the lighting circuits and then fuse ratings?

[Jean Berk]

Thanks Jean - does anyone know what the wattage is for a H4 low and meain beam. I can work out the current drain on the various parts of the lighting circuits and then fuse ratings?

 

Depends on your bulbs. Standard bulbs are 55 watt low beam and 60 watt high beam. I might try some 100 watt bulbs if I'm not satisfied with the results of my new Philips bulbs, new lenses and relay kit.

[pete917]

thanks jean. whats the 100w low beam wattage?

 

I take it the philips ones are standard whattage i.e., 55/60?

[Jean Berk]

thanks jean. whats the 100w low beam wattage?

 

I take it the philips ones are standard whattage i.e., 55/60?

 

Philips are 55/60. 100w are 100/80w.

[pete917]

OK. So ive worked out the fuse ratings through the wiring upgrade for both 60w and 100w bulbs. Ive updated the wiring diagram i posted earlier with a table of fuses required. Ive assumed the battery output is 13.8v and ive rounded up the fuse ratings to the nearest whole number:

 

 

 

 

 

 

The conclusion is that you should make sure tht the main wiring from the battery is gauged to 30A. That way you can add either 60w or 100w bulb and be safe.

Edited July 8, 2007 by pete917

[pete917]

I've now completed the wiring upgrade with OEM relays and I must admit the lights do now seem brighter.

 

Here's what I did:

 

- installed Philips +80% xenon H4 bulbs;

- run a fused (20amp) supply to feed 2 new OEM porsche relays (i've read of some people using 30Amp. This is far too much and wont blow for the circuit. Even using 100w bulbs you should only need 28Amps);

- run the switched feed from headlight switch and main beam switch into control side of two seperate relays;

- then run the switched output from the relays back into the OEM wiring.

- For my wiring in detail see my earlier post in this thread with a detailed before and after wiring diagram.

 

The most tricky thing was mounting the OEM relay holders into their mounts. Just a very tight fit. Tototal wiring time was about 30 mins. I know the Sucro kit is much cheaper, but using the this approach keeps whole thing looking completely OEM.

 

The costs:

 

- Philips +80% £24.99

- 2 x relays £30.00

- 2 x relay holder £56.00

- mini blade fuse holder £3.00

- fuse £0.55

total £114.54

[burgundyben]

a quick question - can any tell me the Watt rating for headlights and main beam for a standard H4 bulb. Also, when you switch to main beam, the dipped element goes out? Is that correct.

 

Did you get an answer to this?

 

I'm in the process of fitting relays and it strikes me that if this is not the case then you could set it up so that when you flick from dip to main the dips stay on as well. So if I had 100/80 bulbs I'd have either 160 watt on dip or 360 watts (!) on main.

 

To do this would require a 3rd relay, being controlled by the main beam out put from the switch with the output from the relay running to the dip beam elements?

 

EDIT - I note from your current/fuse calcs that in selecting a 28 amp fuse for 100w bulb installation you have assumed that both are on together? Or at least thats what is implied.

Edited September 16, 2009 by burgundyben

[pete917]

Its true the 28A fuse assumes both are on at the same time. The fuse is rather redundant however as the two seperate fuses really cover the main and dipped circuits.

[hukent]

Can you get a ready wired kit in the U.K.?

or do you have to get one of these?

http://www.jwesteng.com/porsche/911/hl_relay.htm

[rak]

Not that difficult getting that West Eng kit. Postage is obviously high, but it turns up quickly (ordered mine a couple of months ago and it turned up within a week).