Wiring for ecu question

-
I

InRogue

Well-Known Member
Joined
Feb 2, 2019
Messages
76
Reaction score
30
Location
Winter Park, FL
On my Rambler with 318 swap I'm wiring in the ecu, the 12v run wire from the ignition switch to the resistor/blue wire to ecu, I get that part, the other side of resistor to the + side of coil, I run an extra wire to it from the solenoid of the starter? For 12v at start up? Am I thinking right?
 
Sounds right to me. ( I can not comment on the ECU wire color) you Google mopar electronic ignition there are diagrams
 
InRogue said:
On my Rambler with 318 swap I'm wiring in the ecu, the 12v run wire from the ignition switch to the resistor/blue wire to ecu, I get that part, the other side of resistor to the + side of coil, I run an extra wire to it from the solenoid of the starter? For 12v at start up? Am I thinking right?
Click to expand...


"Depends" on what you mean "from solenoid." What does it have for a starter / solenoid? Does it have two small terminals, IE the GM or Ford style with "s" for start and "I" for igntion? If so, yes, from the "I" terminal to coil +. If you just hav eone solenoid "s" terminal then you need "something else."

Hooking the coil to the "S" terminal will cause a "feedback" situation, where the coil resistor, when running, will try and power the solenoid, and will cause low voltage to the coil, because of the load. If one "s" is all you have, there is a couple of ways.

{For another thing, what are you doing for neutral safety?}

One is to use a solenoid, obviously, with the "S" and "I" terminals. If you need neutral safety, there exists a Ford style solenoid/ relay with a 5th terminal just for torqueflites in AMC products, WITH the "s" terminal

Another is to come off the "S" terminal to the coil, and wire in a nice big diode for isolation. Maybe 5A or larger, 50V PIV
 
....................What did the Rambler have originally for coil resistor bypass wiring? That part of the circuit (in Mopars) is unchanged from points to ECU. In fact, in a Mopar, you can just yank out the breakerless distributor, unplug the ECU, and stick a breaker points dist in there and hook the wire to coil NEG. In an emergency, it will run just like an OEM points setup
 
67Dart273 said:
....................What did the Rambler have originally for coil resistor bypass wiring? That part of the circuit (in Mopars) is unchanged from points to ECU. In fact, in a Mopar, you can just yank out the breakerless distributor, unplug the ECU, and stick a breaker points dist in there and hook the wire to coil NEG. In an emergency, it will run just like an OEM points setup
Click to expand...
That's how I got home the 2nd time my 2nd MSD box died. Took me about 15 minutes to get underway. So keep an extra ballast resistor in your rescue box and a points distributor....
 
67Dart273 said:
"Depends" on what you mean "from solenoid." What does it have for a starter / solenoid? Does it have two small terminals, IE the GM or Ford style with "s" for start and "I" for igntion? If so, yes, from the "I" terminal to coil +. If you just hav eone solenoid "s" terminal then you need "something else."

Hooking the coil to the "S" terminal will cause a "feedback" situation, where the coil resistor, when running, will try and power the solenoid, and will cause low voltage to the coil, because of the load. If one "s" is all you have, there is a couple of ways.

{For another thing, what are you doing for neutral safety?}

One is to use a solenoid, obviously, with the "S" and "I" terminals. If you need neutral safety, there exists a Ford style solenoid/ relay with a 5th terminal just for torqueflites in AMC products, WITH the "s" terminal

Another is to come off the "S" terminal to the coil, and wire in a nice big diode for isolation. Maybe 5A or larger, 50V PIV
Click to expand...
Only
Screenshot_20191124-184721_Gallery.jpg
one terminal, so I guess I can add a Ford type solenoid
 
67Dart273 said:
....................What did the Rambler have originally for coil resistor bypass wiring? That part of the circuit (in Mopars) is unchanged from points to ECU. In fact, in a Mopar, you can just yank out the breakerless distributor, unplug the ECU, and stick a breaker points dist in there and hook the wire to coil NEG. In an emergency, it will run just like an OEM points setup
Click to expand...
No resistor in wiring, neutral safety switch is on the floor shifter...see pix
20191124_185025.jpg
20191124_185018.jpg
 
OK I was not thinking for some reason OF COURSE the Mopar starter solenoid will only have one small terminal LOL

I can't read that diagram very well it appears that the yellow "run" goes straight to the coil? If so, and if you need a ballast (and you do for the Mopar system) then that yellow would go to the "switch" end of the ballast just like Mopar. Then for the bypass circuit you can do as I mentioned.......either run a separate relay like a Bosch to operate with the starter solenoid, and run "straight" 12V to the coil+, or run a diode from the solenoid S terminal to coil +
 
67Dart273 said:
OK I was not thinking for some reason OF COURSE the Mopar starter solenoid will only have one small terminal LOL

I can't read that diagram very well it appears that the yellow "run" goes straight to the coil? If so, and if you need a ballast (and you do for the Mopar system) then that yellow would go to the "switch" end of the ballast just like Mopar. Then for the bypass circuit you can do as I mentioned.......either run a separate relay like a Bosch to operate with the starter solenoid, and run "straight" 12V to the coil+, or run a diode from the solenoid S terminal to coil +
Click to expand...
Your talking about one of these diodes? Current to coil but not back to starter.
Screenshot_20191126-104253_Chrome.jpg
 
You must log in or register to reply here.
-

Back
Top