No spark, ballast resistor only getting 1.5v

[robftw]

I can't figure out why its only getting 1.5 to the ballast resistor, everything else works engine wise.. If anyone has some wisdom on why this would happen i'd appreciate it.

Also on my way home i remembered that i forgot to run a ground wire to the engine.. could something this simple be the reason why it wont fire?

Also, this next one confuses me..

Brake lights work when depressed, and when the car is on both light settings.

Speedo lights work when the car is on first light setting, no other gauges turn on.

All gauges turn on when lights are on the second setting.

Running lights work on both first and second setting, headlights do not work at all

Wipers do not work.

all of my fuses have been replaced.

[SteveJ]

I can't figure out why its only getting 1.5 to the ballast resistor, everything else works engine wise.. If anyone has some wisdom on why this would happen i'd appreciate it.

Also on my way home i remembered that i forgot to run a ground wire to the engine.. could something this simple be the reason why it wont fire?

Also, this next one confuses me..

Brake lights work when depressed, and when the car is on both light settings.

Speedo lights work when the car is on first light setting, no other gauges turn on.

All gauges turn on when lights are on the second setting.

Running lights work on both first and second setting, headlights do not work at all

Wipers do not work.

all of my fuses have been replaced.

1. What ground wire are you referring to?

2. Put the year of your car in your posts. Not everybody knows you have a 76. Different year cars are wired differently.

3. Where were you touching your leads to when you measured 1.5 VDC around your ballast resistor. (Pictures don't hurt, especially when you add arrows to point to things.)

4. Did you check your fusible links? DO NOT rely on visual inspections. Remove them and test resistance/continuity.

5. Did you take voltage readings at the fusebox? What were the results?

6. Are you sure you used the proper rated fuses? Are you sure the fuses are still good?

[robftw]

1. What ground wire are you referring to?

Putting a regular ground strap wire on th ecar

2. Put the year of your car in your posts. Not everybody knows you have a 76. Different year cars are wired differently.

76 body, 77 engine

3. Where were you touching your leads to when you measured 1.5 VDC around your ballast resistor. (Pictures don't hurt, especially when you add arrows to point to things.)

+ positive going to the ballast resistor was only 1.5volts

4. Did you check your fusible links? DO NOT rely on visual inspections. Remove them and test resistance/continuity.

All of my fusible links are brand new, each terminal was getting power

5. Did you take voltage readings at the fusebox? What were the results?

Didn't get this far yet

6. Are you sure you used the proper rated fuses? Are you sure the fuses are still good?

They're oem replacments from carquest numbers on the fuses match

[Walter Moore]

I assume that you were measuring from one post of the ballast resistor to ground. What do you see on the other side? On a car with points, when the points are open it should be the same. On the 1976, there is a pickup point where this would also be true.

If in fact you only have 1.5V on the high side of the ballast resistor, then you have a corroded connection between the ignition switch and the resistor. Or possibly between the fuse box and the ignition switch. It could also be in the switch.

On a points car, when the key is in the position to actuate the starter it by-passes the resistor. I haven't studied the FSM for the later cars to see if this was the case on the cars with electronic ignition.

[SteveJ]

1. What ground wire are you referring to?

Putting a regular ground strap wire on th ecar

If your engine is not solidly grounded to the chasis, you could have problems with the spark, but that's off the high side of the coil.

3. Where were you touching your leads to when you measured 1.5 VDC around your ballast resistor. (Pictures don't hurt, especially when you add arrows to point to things.)

+ positive going to the ballast resistor was only 1.5volts

But for the negative probe, were you touching the chasis, the engine, the other side of the resistor?

4. Did you check your fusible links? DO NOT rely on visual inspections. Remove them and test resistance/continuity.

All of my fusible links are brand new, each terminal was getting power

5. Did you take voltage readings at the fusebox? What were the results?

Didn't get this far yet

Common electrical problems for S30s include

Bad fusible links

Bad fuses

Damaged/Corroded connectors

Connectors that came undone during repairs

Damaged wires

Bad relays/electronics

Poor connection to ground.

With the multiple problems you described, I would think bad fusible links or disconnected/bad connectors. Sometimes you have to start at one end of the circuit (positive or negative battery post) and work through the wiring diagram to get to the other end of the circuit. At least the wires are color coded.

[robftw]

I guess before i do anything tomorrow i will be going through the entire car with some emery cloth and my multi meter, i'll try to write down the voltages of everything.

One thing i forgot to mention, a few places were missing some wires, they have been replaced. Looking back i never checked the resistance of the new wires, could that be causing me trouble?

[SteveJ]

I guess before i do anything tomorrow i will be going through the entire car with some emery cloth and my multi meter, i'll try to write down the voltages of everything.

One thing i forgot to mention, a few places were missing some wires, they have been replaced. Looking back i never checked the resistance of the new wires, could that be causing me trouble?

Okay, what wires were missing? How did you discover they were missing? Did the car run before you replaced these wires? Were you referring to the wiring diagram in the FSM to replace them? How did you replace them?

[robftw]

There was a white wire with a red strip cut near the steering column ignition, A new wire was soldered between the cut (5'' length) There was another in that area too, but i cannot remember the color off the top of my head, this was 2 months ago.

Next, on connector C-13 The yellow wire going to the starter was spliced in, And the Black wire going to the Oil pressure switch was spliced in, along with reverse lights.

They all work according to the multimeter, reverse lights turn on, oil pressure builds when the car is cranking too. I'm not worried here.

My underdash wiring block Was completely taken apart and everything was disconnected , all of the plugs matched up, except for 1 white and 1 black connector (however i think this is just for the AC / Heater according to the diagram)

There was also 1 cut wire here as well, however i soldered that one back together (no extra wire needed)

I was searching last night for a few hours, Another member had the same problem after his car was sitting for a few years. All of my problems may be ignition block related

I took this photo months ago, when i was trying to figure out what the black and white connector went to, Just so happens that my ignition module is in the photo!

And look at that, previous owner wiring job is visible, i think this might be the root of all my problems, and i found it on accident...

edit: just looked at the FSM Engine electrical section on the ignition module, it is obvious the wires are in the wrong place... oh man i hope this is it

Edited June 1, 2011 by robftw

[SteveJ]

The White/Red wire is the main 12VDC that goes into the ignition switch and out to the key-controlled circuits. The fact that it has been hacked it disconcerting. Are there signs of circuits having shorted out in the past in your wiring harness?

IPOs (idiot previous owners) are especially dangerous when it comes to electrical wiring. I'm sorting through some of that now with my 74. Anyway, it sounds like you're getting yourself on the right track. Make sure the wires are correct. Then you can test components.

[robftw]

Okay, fixed most of the wiring and now im getting 11.5-12.5v coming from the coil wire into the dizzy, the teeth inside the dizzy are all broken off, Previous owner messed that up.. We even tried to hotwire it, no go. So im 90% sure its the dizzy.

I ended up getting all of the gauges to work, Wipers now work too, squirts as well.

Headlights are still down, I am not getting power to the harness for them, but i am getting power to and after the fusible links.. hmm.. Maybe bad ground?

Also my right front turn signal (In the grill) Does not work, the bulb is dead.. On these older cars, if the bulb goes out, does the interior indicator bulb stop working too?

[SteveJ]

When you say you're not getting power to the harness for the headlights, what do you mean? The 12VDC+ for the headlights is the infamous White/Red wire. It goes into the switch on the right, and comes out through the Red wire when the headlights are in the #2 position. The Red wire travels to the fusebox and splits into the left and right fuses, coming out Red/Yellow and Red respectively. The 12VDC+ travels to the common pin for the headlights.

Two wires come out of each headlight. One wire is Red/Black. The other wire is Red/White. The two Red/Black wires join as do the two Red/White wires. The wires then go back to the combo switch on the turn stalk. If the switch is in the low beam setting, the Red/Black wire will be connected to ground via the Black wire. If the switch is in the high beam setting, the Red/White wire will be connected to ground via the Black wire.

Get out the wiring diagram & multimeter, and start digging. If you get stuck, post a message describing where you got stuck. Don't be stingy on the details, either.

[robftw]

Okay, when i'm at the front of the car with my multi meter i do not get any power to the headlight plugs with the switch in #2 position

When i checked the fusible links i had power going through them

i had power going through my steering column switch when it was on #2 position \

i do not have any power in my fuse box for the the top two left hand side fuses, L & R i believe they were labeled