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Looking for a hot wire during key on and crank

hpg4815

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Hi,

I got a new tank with internal fuel pump. The wiring harness that goes with the tank has a small wire from the relay that calls for a connection to a fuse or wire that is hot when the key is in the on position as well as during cranking. I tested all the fuses and they are either always on or on when the key is turned one the on position. Not during cranking. This same requirement is mention in the instruction for my fitech. I pulled all that ballast resistor wiring our and went with a ready to run distributor.

Anyone else have this setup and a recommendation on how to get power during key on and crank?

Thanks
 
Blue wire on the 12volt side of the ballast, or in your case you’ve removed the ballast but the wire must still be there?. There are other sources too. Depends in the car, and it’s wiring. Whatcha working on?
 
^^ Sometimes there are extra spades on the fuse box for additional circuits. I would look there first and see if there is an open male spade on the keyed side of the box not the constant hot side. Then you can run your wire cleanly and slide it onto an open terminal. Radio is a 5A circuit correct? Being its using a relay, you should be fine using that circuit.
 
Blue wire on the 12volt side of the ballast, or in your case you’ve removed the ballast but the wire must still be there?. There are other sources too. Depends in the car, and it’s wiring. Whatcha working on?
I unwrapped that wire wrap and removed all the ballast wiring, but look in that area.
27 charger
 
Tap into the fuse for the radio.
I tried all fuses. and they were on all the time or only on during key one. I don't think the radio one was one that showed having power during crank
 
^^ Sometimes there are extra spades on the fuse box for additional circuits. I would look there first and see if there is an open male spade on the keyed side of the box not the constant hot side. Then you can run your wire cleanly and slide it onto an open terminal. Radio is a 5A circuit correct? Being its using a relay, you should be fine using that circuit.
there were two. batt which is always on and another which was on when key turned.
 
He needs start. Not run. The wire going to the ballast and neutral safety switch. Consult a wiring diagram for your car.
 
Stock, you will not find a single circuit with power in run and crank. If the ballast resistor is not in use, simply connect the dark blue (Ign 1, run power only) and brown (Ign 2, ballast by-pass, crank only) wires in the engine harness together for a combined run & crank power supply for aftermarket requirements.
 
Stock, you will not find a single circuit with power in run and crank. If the ballast resistor is not in use, simply connect the dark blue (Ign 1, run power only) and brown (Ign 2, ballast by-pass, crank only) wires in the engine harness together for a combined run & crank power supply for aftermarket requirements.
Ok, this worked but I found out the that one that is on during crank also comes on when the head lights are on. is that expected?
 
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What year and model are you working on? What comes on with cranking? Headlamps are on unswitched power, will be on with the headlight switch no matter the ignition switch position.
 
What year and model are you working on? What comes on with cranking? Headlamps are on unswitched power, will be on with the headlight switch no matter the ignition switch position.
72 charger. Correct. I can have the key in off position and simply turn the head lights on and cranking wire lights up without and actioning of the key. Running light do not 1/2 pull. Full pull does. New wire harness from h&m. Perhaps something was hooked up wrong before I swiped mapped the harness. It this is normal then I will find another solution. Otherwise I would like to fix it.
 
Are you sure you are talking about the brown ballast resistor by-pass wire (Ign2)? In a stock configuration, there is no connection or relation to any light circuits at all. If there is voltage present on the brown wire (Ign2) with the light switch on and the key off, something is cross connected.
 
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Are you sure you are talking about the brown ballast resistor by-pass wire (Ign2)? In a stock configuration, there is no connection or relation to any light circuits at all. If there is voltage present on the brown wire (Ign2) with the light switch on and the key off, something is cross connected.
I don’t have the ballast installed. My setup doesn’t need it. I’m using the wires for the ballast that are part of the engine wiring harness. They work as expected, but it’s just the headlight switch in full on position that provides one of those wires power when the key is in the off position. I agree. That should not be happening. This was my dad’s car and I can see he was messing around with the wires for the dash and also caught some on fire. I bought a new dash harness and put all the wires back the way they were based on the old one. Good chance the old man had something hooked up wrong in the first place. Will dig deeper.
 
when I disconnect the hide away light relay from the dash harness, I don’t have the issue with the one wire from the engine harness that goes to the ballast does not come on when the headlights are turned on. Wondering if that relay is bad or it is hooked up wrong. Anyone have a diagram on how that should be wired? Thanks.

A80C4D3E-03B1-4E32-8631-B69E5AD3D30C.jpeg
 
A test light on the starter relay terminals.
 
found a diagram. The relay for the hide away lights is wired correctly.
 
The concealed headlamp motor harness, wired correctly, is not connected to Ign2. It is connected to Ign1 however. Are you seeing this headlight-on back feed on the blue (Ign1) or brown (Ign2) wire?

I would start at the Ignition switch Molex, trace out the brown wire (J3-12BR) to Bulkhead connector, cavity #22, then on to the ballast resistor connection. Verify nothing has been tapped into it. In a factory configuration there should no other connections to this circuit.

You will not find this circuit at the stater relay.
 
Get a Bosch 30 amp relay, very common, has 4 terminals. 85 + 86 are the terminals that energise the relay coil.

Ground terminal 85. Connect a wire from 86 to the [+] terminal of the ign coil. You will now have power to the relay in start & run positions; the relay contacts can now be used to power whatever you need. The relay only draws a fraction of an amp & will not affect ign performance.
 
Stock, you will not find a single circuit with power in run and crank. If the ballast resistor is not in use, simply connect the dark blue (Ign 1, run power only) and brown (Ign 2, ballast by-pass, crank only) wires in the engine harness together for a combined run & crank power supply for aftermarket requirements.
No longer using ballast but the blue and brown merge into a female spade, on one side, now using CDI and FAST ECU, I struggled finding crank&run on same wire so wired toggle to supply volts for both, but still use key to crank..Kept my original wires for the coil. but not using so should those wires have volts if no longer connected thru ballast or to coil ?
 
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