Mopar ECU

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barbee6043

barbee6043

barbee 6043
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When I change over to the ECU , do I splice into the 2 prong ballast at the side where there are the two blue wires, one goes to coil +, other to firewall, which ONE???? Thanks
 
barbee6043 said:
When I change over to the ECU , do I splice into the 2 prong ballast at the side where there are the two blue wires, one goes to coil +, other to firewall, which ONE???? Thanks
Click to expand...

Leave the coil PLUS wiring completely alone except for the NEG which of course was to the points and maybe a tach

The ECU power wire goes to the "high" voltage side of the ballast, IE blue. One side will have brown and blue, that is to the coil. If any question, pull the connection you believe it to be off the ballast, and confirm that wire has "battery" when key is in run.

Make DARN sure both the regulator and ECU are grounded. Scrape away paint behind the bolt holes, use star lock washers, and consider upgrading the engine to body jumper. I like to use a short "starter cable" that is eyelet--to eyelet about a foot long. Bolt it to the holes in the rear of the driver side head, and to the firewall. One way is to the master cyl. stud
 
67Dart273 said:
Leave the coil PLUS wiring completely alone except for the NEG which of course was to the points and maybe a tach

The ECU power wire goes to the "high" voltage side of the ballast, IE blue. One side will have brown and blue, that is to the coil. If any question, pull the connection you believe it to be off the ballast, and confirm that wire has "battery" when key is in run.

Make DARN sure both the regulator and ECU are grounded. Scrape away paint behind the bolt holes, use star lock washers, and consider upgrading the engine to body jumper. I like to use a short "starter cable" that is eyelet--to eyelet about a foot long. Bolt it to the holes in the rear of the driver side head, and to the firewall. One way is to the master cyl. stud
Click to expand...



Edited> I got it wired by diagram. I have full charged batt. 12.5 v in and out fire wall at the big black and red wires, firewall connections cleans,, I have 12 .3 v at ballast in run Ign on, when I hit start, ign 2, I only have about 8.5 v there at ballast wire cranking. No fire at coil wire grounded to valve cover, New coil and plug wires.
Next I will do jumper from batt. to coil + and see. IF nothing then, it tells me what!??????? Bad coil ( new)!???????
 
Last edited:
hangn0ut said:
What's voltage at starter relay while cranking?
Click to expand...

Starting: Big terminal at starter relay: 9.5
Batt. 12.3
ballast 11.5
coil + ; 8.5
I have 12.4 in and out hot wires at firewall. New coil, amp. gauge bypasses
I can't find my in line spark tester, but I see no fire with coil wire at valve cover.
 
The low coil voltage indicates either the bypass (IGN2) from the ignition switch has a problem or that something is dropping voltage TO the ign switch. This also might be (one of the usual suspects) ..............might be the bypass wire (usually brown) coming through the bulkhead

I'd check power TO the ign sw in 'crank' and power on the ign2 terminal at the ign switch

Be CERTAIN the ecu is grounded

Make certain the ECU is NOT hooked to the coil side of the ballast
 
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