New starter now gauges and radio don't work update

John Barbieri

True Classic
Ok, I've got this narrowed down. So I installed a new starter in a 79 1500 and for some reason my gauges, radio, turn signals and who knows what else stopped working. I have it narrowed down. The guages, radio and signals do work, WHILE I'M ENGAGING THE STARTER! As soon as the car fires up and I put the key back to the on position the car runs but everything stops working again. Could it be that I put a connection on the starter in the wrong lead? I have a thick green wire from the battery and a black one from the alternator on the terminal closest to the firewall. The wire on the spade connector and the other one that just pops on. Are these connected to the correct terminals? Also, I noted a spark when I reconnetected the negative terminal to the battery. Tia
 
Time to be looking into the ignition switch itself. There are two leads out of the switch that provide switched hot for the gauges and everything else that’s only working when the ignition is on - these are supposed to be hot when the key is in the run position. At least one of these two is also hot when the key is in the start position, so that you’ll have gauges and ignition while cranking.

So first check the continuity through the switch with the key in various positions: disconnect all the switch connectors, put one lead of your multimeter on the always-hot input to the switch, and then look for continuity at the other leads with the switch in the off, start, and run positions.
 
Time to be looking into the ignition switch itself. There are two leads out of the switch that provide switched hot for the gauges and everything else that’s only working when the ignition is on - these are supposed to be hot when the key is in the run position. At least one of these two is also hot when the key is in the start position, so that you’ll have gauges and ignition while cranking.

So first check the continuity through the switch with the key in various positions: disconnect all the switch connectors, put one lead of your multimeter on the always-hot input to the switch, and then look for continuity at the other leads with the switch in the off, start, and run positions.
Now the guages don't work at all, even while cranking the engine. Extremely frustrated.
 
Now the guages don't work at all, even while cranking the engine.
That’s still consistent with a flaky ignition switch or a flaky ground.
I’m away from all of my wiring diagrams, so can’t help with specific wires and colors.... but either 12v power isn’t getting to the instrument panel or its ground isn’t grounding.
Extremely frustrated.
It’s OK to think about burning the car or pushing it off a cliff - but don’t act on the impulse.
 
That’s still consistent with a flaky ignition switch or a flaky ground.
I’m away from all of my wiring diagrams, so can’t help with specific wires and colors.... but either 12v power isn’t getting to the instrument panel or its ground isn’t grounding.
It’s OK to think about burning the car or pushing it off a cliff - but don’t act on the impulse.
Not the ignition. Tested a spare ignition switch I had laying around for continuity, plugged it into the car and same result. Also, still getting sparks when I reconnect the negative to the battery even with the ignition switch completely disconnected. Wtf.
 
And n
Not the ignition. Tested a spare ignition switch I had laying around for continuity, plugged it into the car and same result. Also, still getting sparks when I reconnect the negative to the battery even with the ignition switch completely disconnected. Wtf.
And now I find the car will start without depressing the clutch! What the f*** on hell has happened to this car. All it needed was a f***ing starter and now I have a f***wad of electrical problems thst were never there before. Anyone wanna buy this pos before I push it of a cliff?
 
I have never seen an x1/9 with a clutch switch for the starter (not a bad idea) but never seen one. I would try unplugging the key switch and jumpering the wires. I am betting you have a bad key switch, or connection their
 
And n

And now I find the car will start without depressing the clutch! What the f*** on hell has happened to this car. All it needed was a f***ing starter and now I have a f***wad of electrical problems thst were never there before. Anyone wanna buy this pos before I push it of a cliff?
I must have the starter wired wrong or the place that rebuilt it wired something wrong inside because everything works provided that I hold the key in the start postion. Guages, radio, signals, wipers, everything. The power is not going through in the on postion. I've tested and tried two ignition switches with the same results. Can anyone show me what wires go to which leads on a 79 1500 carburetated? Pics would be appreciated. I can't come up with anything on a google search as far as a pic goes. Either I hooked up the starter wrong or the place that rebuilt it got it wrong. When I removed the starter there were two leads on one of the terminals, one from the battery and one from the alternator. There is the green wire with the spade connected thst dosent go anywhere else and the push on elbow connector. The other terminal in the starter just has a wire going into the starter itself. I have the wire from the alternator and battery both connected to the terminal on the solenoid closet to the firewall. Either I've connected something wrong that is killing power to the accessories and gauges in the on position or soemthing is not right with this starter.
 
I have never seen an x1/9 with a clutch switch for the starter (not a bad idea) but never seen one. I would try unplugging the key switch and jumpering the wires. I am betting you have a bad key switch, or connection their
Two key switches, both tested for continuity in all key postions, same results.
 
Are you a member at Mirafiori.com? They have the '79 wiring diagram in the library; you must be a member to access.
https://www.mirafiori.com/forum/viewtopic.php?f=80&t=97555

Red wire from ignition switch goes to terminal 50
Battery and alternator wires are black and go to terminal 30
the internal connection to the starter has nothing else attached to it
they show a white/red wire going to the gulp valve, goes hot when starter engaged
that's all.
lights/gauges only share the ignition switch (but only from the 'run' position, the 'start' position is only connected to the red wire to terminal 50).
 
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Are you a member at Mirafiori.com? They have the '79 wiring diagram in the library; you must be a member to access.
https://www.mirafiori.com/forum/viewtopic.php?f=80&t=97555
I just need to know what wire go where on the starter so I can make sure it's connected properly and rule that out. I really don't get it. Checked the ignition key switch with a multimeter as well as the female end and there's power there,its just not making it to the guages and accessories once the car is started and the key is in the on postion. I am ready to just wire everything directly to the battery on its own fuse box and be done with this ****. Everything worked as it should until I put a rebuilt starter in it.
 
Are you a member at Mirafiori.com? They have the '79 wiring diagram in the library; you must be a member to access.
https://www.mirafiori.com/forum/viewtopic.php?f=80&t=97555

Red wire from ignition switch goes to terminal 50
Battery and alternator wires are black and go to terminal 30
the internal connection to the starter has nothing else attached to it
they show a white/red wire going to the gulp valve, goes hot when starter engaged
that's all.
lights/gauges only share the ignition switch (but only from the 'run' position, the 'start' position is only connected to the red wire to terminal 50).
I don't get it, there's continuity at the switch in the run position, there's power at the switch in the start postion and they gauges and everything else only work on the start position. There's power and continuity at the female end of the ignition switch connector. The starter is all connected as it should be. The fuses are all good and the grounds must be fine too, otherwise the gauges wouldn't work while the engine is cranking. Anyone have any ideas? Because I've about run out.
 
I remembered how to do this
'79 starter.png

good luck!
Special thanks to Chris Granju for posting this there!
 
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Are the red and blue/black wires on the right ignition switch terminals?
 
I still stick with jumping the terminals.. something is changing in the key switch area. if the start position brings the gauges to life.

then you KNOW exactly what is changing and when.
 
Recap:
- You've tried two switches and gotten identical continuity results with both
- The gauges worked properly with one of those switches before the starter replacement
- Once started, the car runs except for the gauges not working
- When you turn the key from off to run without trying to start it, the gauges don't work (am I understanding this properly? not stated explicitly from the previous threads)
- The alternator rebuilder said you had a "bad" diode but didn't say whether that meant open or shorted. Has the bad diode been replaced?

One other question: There are other things (headlights, turn signals, brake light, reverse light, vent fan, .....) that should operate when the key is in the run position but not the off position. Which if any of these are behaving properly?
 
Recap:
- You've tried two switches and gotten identical continuity results with both
- The gauges worked properly with one of those switches before the starter replacement
- Once started, the car runs except for the gauges not working
- When you turn the key from off to run without trying to start it, the gauges don't work (am I understanding this properly? not stated explicitly from the previous threads)
- The alternator rebuilder said you had a "bad" diode but didn't say whether that meant open or shorted. Has the bad diode been replaced?

One other question: There are other things (headlights, turn signals, brake light, reverse light, vent fan, .....) that should operate when the key is in the run position but not the off position. Which if any of these are behaving properly?
Yes to all, that's all correct. The only things I've seen working with the key in the on postion are the headlights, dash lights, door buzzer, horn, alternator light. If I crank the starter everything works fine while the starter is being cranked.
 
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