Need a TCI test on a 4R0

[BA80]

That was wrong, 2 &3 are on the same coil and pick up. My sideways thinking again. OCD

[CaptonZap]

We had the same thought about the emergency stop switch early on, but when you check from the black/white at the TCI to ground you basically bypass the switch.

True, but if there is a short to ground in that circuit, or the switch is shorted internally, it would draw the voltage down when you measured at the TCI. Remember that the tilt switch is NO, makes on tilt.
Another thought is that the diode inside may have opened up, which would explain the low voltage. It wouldn't affect the running, since the internal workings would still have the 6 V necessary to operate, since they couldn't be shorted out through the diode. But then the tilt switch would't kill the motor.
Just stuff to check.
CZ

[motoman]

C.Bug. would you believe a possible batt.issue? It initially may show 12+v. Start it up, then kill it in gear which leaves the lites including head lite on. Dom't touch anything and just put a couple wires across batt. from a CORRECTLY working volt meter across batt. What's the reading? These systems are NOT that new, even tho the regulator is solid state. In other words, in order for the rectifier to exite and allow a correct charge rate, you need a minimum of 12v initially at the battery when starting. If it doesn't, a failing chrge rate will follow. Bike may start at a lower rate, but you'll occassionally have to add distilled water to it..........reason beig a faulty conection or poor groung. Regulator has no way of knowing that, so it allows alt. to just keep charging at a false rate cause of a poor connection or poor ground...........consquently, it occassionally needs distilled water added due to a constant overcharging rate. In 34yrs. with ny bike, have NEVER had to add distilled water to any of the batteries. In other words, your short rides are showing a voltage drop, which could turn into all four cyls. dropping out with a longer ride by time battt, ......'gives up the ghost''. 'For Ian, if your reading, is ONE of the reasons why I get 8yrs. out of my batteries without a charge. Since the Venturer would sit more than a year, I would initially put a 1amp charger on it BEFORE I even considered hitting the start button.............follow me here as tothe reasoning?

[dbeardslee]

And, only the wire to the tip over switch. Once again, the tip over circuit will affect 4 cylinders, not just 2.

Another thing that doesn't make sense, when I read back through the other thread he stated it was cylinders 2 & 3. They share nothing fuel or ignition related.

What do you mean - they share a coil and a pickup coil.

Must have been posting at the same time - I saw post #16. Since I can't remove the post, just consider this a message from The Department of Redundancy Department.

[motoman]

C.Bug. would you believe a possible batt.issue? It initially may show 12+v. Start it up, then kill it in gear which leaves the lites including head lite on. Dom't touch anything and just put a couple wires across batt. from a CORRECTLY working volt meter across batt. What's the reading? These systems are NOT that new, even tho the regulator is solid state. In other words, in order for the rectifier to exite and allow a correct charge rate, you need a minimum of 12v initially at the battery when starting. If it doesn't, a failing chrge rate will follow. Bike may start at a lower rate, but you'll occassionally have to add distilled water to it..........reason beig a faulty conection or poor groung. Regulator has no way of knowing that, so it allows alt. to just keep charging at a false rate cause of a poor connection or poor ground...........consquently, it occassionally needs distilled water added due to a constant overcharging rate. In 34yrs. with ny bike, have NEVER had to add distilled water to any of the batteries. In other words, your short rides are showing a voltage drop, which could turn into all four cyls. dropping out with a longer ride by time battt, ......'gives up the ghost''. 'For Ian, if your reading, is ONE of the reasons why I get 8yrs. out of my batteries without a charge. Since the Venturer would sit more than a year, I would initially put a 1amp charger on it BEFORE I even considered hitting the start button.............follow me here as tothe reasoning?

I'll give you one more example of a failed batt. just last year: Went to start the wife's Escape and couldn't even get a click out of it. Turned key of, raised the hood and checked batt, with a multi meter. It showed 12.7v......hmmmmm, interesting. Turned key bsck on and checked voltage at batt. again.......hmmmm........4volts.Hmmmm........unkno wingly initially, it had four sulfated cells...........go figure. Wanna be careful and maticulate doing the battery voltage check .

[dbeardslee]

And, only the wire to the tip over switch. Once again, the tip over circuit will affect 4 cylinders, not just 2.

What I'm wondering is why it's only reading zero volts. He said when he first turns the ignition on he gets 1.3V, then hears a clicking sound, and it drops to zero. Is something shorting out internally on the TCI, and if it is where is the voltage going? Like I said he's resoldered it four times, and ViperRon brought up some interesting points about soldering on a TCI and unintentionally connecting traces. CBug has been testing and testing and testing, and we're just trying to either rule out the TCI as the problem or confirm that it may be the culprit. Sooner or later something's gotta give.

[motoman]

What I'm wondering is why it's only reading zero volts. He said when he first turns the ignition on he gets 1.3V, then hears a clicking sound, and it drops to zero. Is something shorting out internally on the TCI, and if it is where is the voltage going? Like I said he's resoldered it four times, and ViperRon brought up some interesting points about soldering on a TCI and unintentionally connecting traces. CBug has been testing and testing and testing, and we're just trying to either rule out the TCI as the problem or confirm that it may be the culprit. Sooner or later something's gotta give.

Good voltage)12.5 or better) in the circuit would be a good start.

[BA80]

What do you mean - they share a coil and a pickup coil.

Must have been posting at the same time - I saw post #16. Since I can't remove the post, just consider this a message from The Department of Redundancy Department.

Just what I said. #1 and #4 share a ignition coil and pick up coil, and #2 and #3 share an ignition coil and a pick up coil.

A wasted spark system fires the ignition coil during the compression stroke and the exhaust stroke WITH it's paired cylinder.

[Prothec]

I have an '81SH with a 4R0 TCI and tested 0v at the b/w wire. I checked voltage at pin #3 b/w through the back of the connector with the ignition ON and stop switch ON. Voltage at the battery with ignition ON is 12.14v.

I test-started it on Sunday and it's firing right up and running strong on all cylinders.

[CatatonicBug]

I have an '81SH with a 4R0 TCI and tested 0v at the b/w wire. I checked voltage at pin #3 b/w through the back of the connector with the ignition ON and stop switch ON. Voltage at the battery with ignition ON is 12.14v.

I test-started it on Sunday and it's firing right up and running strong on all cylinders.

Wonderful! So, now at least I know I'm not crazy! (well, at least not with this issue)

[dbeardslee]

That's good news on the TCI, and tends to eliminate it. I'm thinking the next thing to do is to get those coils good and hot, and recheck your resistance readings as Greg suggested. And pay particular attention to the right hand coil that feeds 2 & 3 as that's the one that seems to have issues. What would probably be best is to run it until it starts acting up and check it immediately. Maybe TC had something with the graphite core wires.

[dbeardslee]

One other thing - did you ever run Randy Rago's TCI quick test? It might help to determine if the problem is between the TCI and coils or the TCI and the pickups. You want to run your carbs dry so it won't start when you crank it, and run the test on both coil wires. Probably best to do it when everything is hot and the problem is exhibiting itself.

[DAVINCI]

+1 dbeardslee,

USE AN ANALOG METER, a DMM is too slow

[CatatonicBug]

Just to confirm, yes, I ran Randy's test. I got the voltage swing on the analog meter, just like the video, pointing to the pickup coils.

Rode to work this morning, a decent portion over 85mph, with no issues at all. I get a feeling there was some strange disconnect in the mid-way connector for the pickup coils, behind the fuse panel. Once I opened it, put some terminals into it to test the connection between there and the TCI, and put it back together, everything seems to be happy again...

If nothing else happens, I learned a LOT about the TCI and the pickup coil circuit during all of this troubleshooting.

[dbeardslee]

Just to confirm, yes, I ran Randy's test. I got the voltage swing on the analog meter, just like the video, pointing to the pickup coils.

Rode to work this morning, a decent portion over 85mph, with no issues at all. I get a feeling there was some strange disconnect in the mid-way connector for the pickup coils, behind the fuse panel. Once I opened it, put some terminals into it to test the connection between there and the TCI, and put it back together, everything seems to be happy again...

If nothing else happens, I learned a LOT about the TCI and the pickup coil circuit during all of this troubleshooting.

What would be real interesting is if you retested the voltages at the TCI after cleaning that connector and see if you're still getting 11.2V, or if it's back up to 12. That would tend to confirm that you nailed the problem.