Help - electrics!

OK, on my 1972 246GT - I have no instruments working (tach, dials) apart from the speedo... dash lights are working

Heater not doing anything and brake lights not working

Have checked fuses and they seem ok

Is there anything which is immediately apparent to anyone?

I did have a couple of loose wires near the fuse box which I have connected to where I think they go - to no avail...can post a pic if anyone feels that may help

Also going to replace the cigarette lighter so if anyone has any advice for that I would really appreciate

Thanks guys

Matt

 

You seem to have connected the wrong wire to the output of fuse#13 (8A), this is the instruments/heater/brake light supply.

If you are unsure which wire is the correct one, set your multimeter to resistance/Ω, connect one probe to the wire going to both fan switches, and use the other probe to test each of the loose wires. If you find the one with less than 2Ω, then thats the right one.

This might be helpful:
http://www.dinoplex.org/Ferrari246GT_E_ColorWiringSheet.pdf

Good luck,
Adrian

 

Thanks Adrian really appreciate you getting back to me... not sure about the Ω business but will have a go

There is also a black wire with a round connector (so as to be screwed into body I assume) so I guess this is an earth - but there doesn't appear to be a place for it to be screwed to. It is connected to the fuse board (on the side nearest the wing) and comes through the aperture in the fuse board but doesn't appear to be long enough to reach anything... any clues?

Thanks

Matt

PS Don't suppose anyone knows what colour wire would be connected to Heater, Instruments etc?

 

Ω (Ohm) is the resistance mode of the multimeter, it helps you identifying the correct wire when in doubt, a simply continuity tester does the same job.

The wire going to the fuseblock on the '72 car seems to be light blue, the corresponding fuse #13 is labeled "Inter.Ventilat. Stop Lights Instruments". The black wire with the ring connector is usually fixed to one of the installation screws of the nearest relay.

Could you post a photo of your fuse blocks and wires?

 

there is a great wiring diagram on the net.
search dno plex, it also shows internal wiring of the dino plex if you have any interest. I had the diagram blown up as the entire wiring of my car was a disaster on which I have been working on for weeks now. If you want, I could send you a diagram of each circuit you have interest in

clay

 

Thanks chaps

Have (hopefully) attached a pic which shows my fusebox

The longer blue wire looked like it needed to go to main fuse as it's length looked in keeping for that, black wire hopefully is sorted and the white wire had remnants of being attached to 3rd fuse from right...so re-attached. No difference though

I have downloaded a beautiful colour wiring diagram but have to confess, not being an electrician, it has me a bit stumped

Gonna have it looked at by someone with a clue what they're doing but hoped that someone may be able to enlighten me as to where these missing wires may go

btw the yellow stickers on the pic are so I remember which ones I re-attached

Thanks

Matt
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Can you also send a photo of the other side of the fusebox with the relayboard? I've attached the fuse box label you are missing, might help a bit with the fuse identification.

What color is the wire on the other side of fuse #13? If i remember this correctly, the input side (supply) is on the inside (tire), and the fuse output is on the photo you have posted.

Keep in mind that the wire colors in the diagram show the functional group (e.g. orange is +12v ignition on, red is +12v permanent on etc.), not the actual wire color itself.
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Matthias had a good point, which '72 model (type, number) do you have? The fusebox and relayboard are different between the models.

 

yeah

fuse #13

should not have any current until you turn ign key on. Powers up all the loads you are missing and then some. The first thing it powers up is the ventilating switch and the heating fan switch. The wire is the 5th fuse from the left. remove the dash and check the power to the gauges, when you turn on the ign, they shoud show current to all the gauges.

good luck

 

I'm afraid I bailed!

Got the car over to R&D in Manchester and they have got all instruments working apparently - get it back on Tuesday

Something to do with the fuse-board rather than idividual wires... will find out so that I can post up in case anyone else has a similar problem

Thanks for all the advice though chaps

Matt