Taco wiring

horacecopeMember

Anybody got a diagram or picture of the wiring on the back of the taco. Can't seem to find anything on Pantera place website and I need to know if mine is wired correctly. Wiring diagram just shows +ve and -ve but not colour specific.

Just finishing restoring my car and when I turn on the ignition the gen light comes on correctly but the rev counter goes to max. I see on the diagram a 12v LB comes from fuse 12 and then via a white to the gen light.

If the taco goes to max have I got the polarity of the +ve (LB) and the -ve (B/BK) the wrong way round on the back of the taco or what would cause the taco to go to max.

Secondly the amp guage, Once the 2 heavy wires are attached to the back does it bring a lot of the systems hot via the two pinks like all systems from fuses 7,8, 9 plus headlight switch etc etc. My windscreen wipers came on as I attached the battery for the first time and didn't realise they were on the hot circuit. Little concerned that so many systems seem to be on the hot circuit so is this normal. Does the amp guage only show drawdown or charging, is it not a switch of any sort.

Cheers
Horace

6/25/166:02 AM

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jag13catMember

Horace; You're in the right place www.panteraplace.com. Scroll down to the E section, and in the left column, it should show "Electrical Diagrams-new". Click on it and scroll down almost to the bottom of the page and there are a number of electrical diagrams, one being colorcoded.

6/25/166:26 AM

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horacecopeMember

Hi Jag

Thanks but I have been onto the Pantera place website and diagrams. I also have a paper copy of the wiring diagram.

What I need is which is the -ve terminal and which is the +ve on the back of the taco, mine is not marked which. Also would having them wired the wrong way round cause to taco needle to go to max on ignition turn on.

Cheers

6/25/166:43 AM

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liv1sMember

Here's a pic of the back of an old Tach with the wires on it.

The tach signal wire is Blue/Black and plugs to the signal lead near the center of the housing.

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6/25/1610:27 AM

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horacecopeMember

Thanks, thats exactly the same as mine is wired so no idea why the taco needle should go to max on ignition turn on.

The heavy B/BK from the back of the taco I have going to the -ve side of the coil

The heavy LB also on the back of the taco goes to fuse 12. From the connector side of the LB is a White going to the charge light on the speedo. The other side of the charge light is a B/Bk going to the ALT.

Anyone any idea why the taco should do what its doing on ignition on, is the taco possibly knackered. I have no idea from studying the wiring diagram and I don't have access to another taco to swap over to try

I have a new Powermaster single wire 100amp ALT fitted with a side terminal for gen light. I also have a new Ignitor 111 coil with +ve and
-ve terminals.

Cheers

6/25/1612:40 PM

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robbieMember

This "taco" talk is making me hungry. :-))

6/25/161:41 PM

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horacecopeMember

OK "Tachometer" and not the Mexican food,

6/25/162:56 PM

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liv1sMember

Does the tach needle still go to full deflection with the signal lead disconnected?

6/27/1610:55 AM

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horacecopeMember

Yes it does.

I have disconnected the signal wire and the needle still goes to max on ignition turn on

I am considering switching the 12v and the signal wires around but I am a little concerned I might damage the Tacho internally.

If I do this is there anyway of testing the tacho using the signal wire, if so how?

Engine is not up and running at present and despite several calls to other DT owners I have been unable to borrow another tacho to try and determine the problem

cheers

6/27/1611:23 AM

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jfb05177Member

have you "opened" the tach to see the circuits?
if so, you could check the potential accross the movement. I suspect the low/ground side transitor is conducting