car won't start until I release the key from the cranking position.

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BTW there is an error in the above schematic. Look at where the 2 brown wires come together above the voltage regulator; there should be no wire from that connection to the I terminal of the VR. Otherwise, you would always bypass the low resistance side of the ballast that is in series with the coil + when the key is in RUN.

There is no 'start side' and 'run side' of the dual ballast. The high resistance side feeds a power signal to the ECU (which was done away with later) which I understand is simply a control signal. The low resistance side of the ballast is in series with the coil as in the single ballast system.

In START with the dual ballast, power is fed from IGN2 (on the brown wire from the ignition switch); this puts +12v direct to the coil + (as in the single ballast system) and also BACKFEEDS VIA THE LOW RESISTANCE SIDE OF THE BALLAST, jumpers over to the high resistance side of the ballast to feed the ECU power input (Blue-Yellow wire) and also through the high resistance side of the ballast to the ECU 'control' (Green-Red). The above described backfeed via the low resistance side of the ballast to the high side and on to the ECU is why a blown low side resistance in the dual ballast will cause the symptoms that the OP is experiencing.

When the key is released to RUN, then power is fed from IGN1 (on the blue wire from the ignition switch) to both sides of the ballast resistor at the end where the 2 halves are jumpered together; this feeds power to the coil + via the low resistance side of the ballast, to the ECU main power lead (Blue-Yellow) and via the high resistance side to the ECU Green-Red wire to keep it operating.
 
OK, probed all poles of the ballast in start and run position.
Blue, turquoise/yellow(these two have a black jumper) and green/red all go from bright to dim: run to start
brown goes dim to bright: run to start.
Looking at the schematic, my ballast resistor appears to be upside down....lol
I'll flip it at halftime and see what happens.
Is that possible?
just looked, not possible due to the dimple on the firewall.
My brown and green wires are opposite of the above schematic
as well as the blues.
 
I checked the resistance on both resistors I have and they were the same.
5.0 and 1.2 on both.
 
So I flipped the ballast....with the open notch on the resistor towards the driver side , brown wire in the top right position, the car starts instantly. ....it appears the ballast was installed 180° out...lol
I really appreciate all of the input from everyone.
Thanks alot.
It seemed to not only enlighten me, but a few others as well.
thanks again, I will most definitely have more questions in the near future, and I'm glad to have such a deep pool of knowledge to access!
 
LOL, well at least it was that easy! The high resistance side in series with the coil must've been lowering the spark energy enough that it would not keep firing the engine cold after starting.
 
No, they are both keyed. There is a protruding "dimple" on the firewall that I thought fit into the open slot on the BR, putting the open slot towards the passenger side. This put the connectors upside-down and on the wrong ends of the BR.
Does this make me the "fool" in their "fool proof" design? lol
 
I just found this posting after I decided to research this problem myself. After doing some voltage checks on my car I am only getting about 9.5 volts at the coil during cranking. I also noticed that my coil according to the polarity markings on it is connected backwards when checked with my meter observing polarity. According to Doctor Google I found some postings on other sites which claimed your car could still run, although you might have reduced spark and other performance issues? Could someone tell me also what voltage you should see at the coil when the car is running? I did measure 12vdc going into the ballast resistor.



IMG_1661.jpg
IMG_1662.jpg
 
Hi you should not bring up old threads, rather, start your own "new" one. Key in "run" engine stopped, the battery is nominal 12V depending on load. Current goes through the coil and that draws down the voltage through the resistor. In this case maybe 6-10V or so, it will vary

Running, depends on system voltage. If the alternator is turning fast enough to bring the system up to nominal 14V at the battery, now you will see perhaps 8 or 10 -to- 12V at the coil

Cranking depends on what the battery is sucked down to when cranking. "In theory", coil + should see whatever the battery is during cranking. If the battery is pulled down to 11.5V then very close to that should appear at the coil

ALL these cars, unless the wiring has had some serious work, and that includes the ignition switch CONTACTS themselves---all of them suffer voltage drop of various amounts
 
COIL polarity. Yes, the coil + marking should go to the battery supply side Reversing them may cause less spark power and may erode the plugs more quickly
 
67Dart273 said:
Hi you should not bring up old threads, rather, start your own "new" one. Key in "run" engine stopped, the battery is nominal 12V depending on load. Current goes through the coil and that draws down the voltage through the resistor. In this case maybe 6-10V or so, it will vary

Running, depends on system voltage. If the alternator is turning fast enough to bring the system up to nominal 14V at the battery, now you will see perhaps 8 or 10 -to- 12V at the coil

Cranking depends on what the battery is sucked down to when cranking. "In theory", coil + should see whatever the battery is during cranking. If the battery is pulled down to 11.5V then very close to that should appear at the coil

ALL these cars, unless the wiring has had some serious work, and that includes the ignition switch CONTACTS themselves---all of them suffer voltage drop of various amounts
Click to expand...

Ok thanks for the info, both wires going to my coil were black so it's easy to see how someone could reverse thing. I'm sure many people have been under this hood before me. Thanks.
 
Had this issue, and what I found.

Run puts 12v to the ballast and drops V to the coil to about 7-8 volts.
Start bypasses the ballast and puts full voltage to the coil to help starting when the voltage is being pulled down by the high current draw of the starter.
* the key is - “Run” drops out when key is turned to start.
And the ECU is fed from the run side. - voltage to the ECU is backfed thru the ballast and anything else on the run circuit can pull the voltage down during cranking. - “Run” has instrument gauges, voltage regulator, and some people wire their electric choke to it. Any extra current draw on the “Run” circuit - fuel pump, tach, stereo, whatever, Pulls the voltage sown and the ECU will not get sufficient voltage.
* jump the battery to the run side of the ballast.
Bet it fires right up.
But won’t turn off till you pull the jumper!

Ymmv
 
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