Seca650 No spark

I did visualy check the wiring

 

consider that both connectors on the diagram are out 180 degrees

you have one connector 6 position in correctly by visiual comparison to other tci units but backwards from diagram
your 4 position connector does not match visiual comparison to other tci units but matches the diagram.

so your choice is to change wiring to 6 position connector to match diagram or change 4 position connector to be 180 out from wiring diagram.

 

Well ladies and gentlemen by comparison to the other Seca 650 I saw today it seems that indeed the wiring for the 4-pin connector on my bike is WRONG! The 6-pin connector, however, is correct. I included a pic for you all to see. Now, I'd love to tell you that I changed all the wiring around, connected it to the TCI, and the bike turned on but alas, nothing changed. However, all is not lost. I gave myself the benefit of the doubt and did not take the gentleman's TCI to use on my bike. So, the next thing to try would be another TCI. I'm hoping that firing the bike with the wrong wiring into the TCI could have possibly fried mine. Having said that I conducted the same tests I did before and here are the results.

First test was connecting the positive probe to the R/W wire and a negative to ground and then turning on the bike to see if it started at a lower voltage then went to a higher voltage. It did not. When I turned on the bike I read 11.85volts and it did not change. I tried the same test with the orange and then the grey wire and all the results were exactly the same. 11.85 volts. This is a different, however, from conducting the tests earlier. If you remember, when I turned the key on the R/W test measured at 9.98volts and both the orange and grey wire measured 1.2. Although, they were all in different places before so maybe this is a bad comparison.

I then tried plugging in the XJ550 Maxim TCI that I have laying around and it also did not work. I also tried the previous tests with this TCI and got the same results.

So, is it worth grabbing the TCI from the other bike? If everything as far as the wiring were fine would the Maxim 550 TCI have worked?

I wish I had better news. Nevertheless, I deeply appreciate everybody's help.

 

Yes knowing that the wiring is the same for the XJ550 and the XJ650 the XJ550 TCI should have at least produced a spark, and looking at published timing numbers would have most likely run fairly well.

I would say yes to trying a known good TCI now that the wiring is correct.

It's difficult to visualize what would have happened with the original wiring configuration, particularly since there are no schematic diagrams available for the TCI's. However, the fact that the orange and grey wire that normally connect to the coil primaries were connected to the B+ and return, and they were reading so low suggests a significant current was flowing. Therefore, it wouldn't be far fetched to assume internal damage caused by the incorrect wiring.

Another indication the TCI is blown as either the gray or orange wire should go to about 1.2 volts for approximately 2 seconds when the key is switched on. The only other thought here is be sure to leave the ignition cutoff (B/W wire} disconnected for the time being just in case there is a problem with the safety circuit disabling the TCI. You might also recheck the pickup coil resistance at the TCI connector just to be sure they are OK. I would also suggest checking the pickup coils to ground as part of that test - they should ohm open to ground. I believe that the DC resistance of the coils is needed to initiate the momentary low on the orange or gray wires, and of course a pulse is required after that to change the TCI mode from standby to operate.

 

edited my rant did not read above post

 

The way I read the below the wires were corrected and the original TCI did not work as well as the XJ550 TCI.

 

We have spark!!!!! I had about 15 minutes today to try and and fire it up with the new TCI and it worked! Here's the thing though, I also took Rooster's advice and disconnected the B/W wire. I had one try to do this today and I just went at it from all angles. Lo and behold there came the spark. With about 3 minutes left instead of analyzing the situation I became a little eager and tried to pour a little gas down in the carbs in hopes I might get a little firing action. Nothing . Will double check tomorrow or sometime to find out which action actually got the bike to spark and then move on to the next thing..

 

starter fluid will give you better results.

 

Ladies and gentleman we have liftoff. It was in fact the wiring. Thanks XJ550h for discovering that. The TCI is fine and was not fried but I did have to take Rooster's advice and disconnect the B/W wire in order for everything to fire up. Is this because of the side stand switch? I also noticed that the headlight did not turn on when the bike fired up.
I'm kind of curious why the wiring was screwed up in the first place. For all I know this bike hasn't been started in 10 years. The gentleman I bought it from said he had it running but I'm beginning to suspect that in reality he didn't know how to fix it so he got rid of it. The choke and throttle cables were also swapped along with the fact that the carbs were all dirty and I had to spray carb cleaner into them. When the bike fired up it produced brown smoke which I'm guessing is brown rust burning out of the exhaust. Nevertheless, the bike sounded really good. The charging system is excellent idling at around 13.5 volts and went up to around 14.6 when I revved it up to 3000rpms.

The next thing on the list is to rebuild the master cylinder. The whole spring and piston assembly inside the cylinder needs to be rebuilt. Are there any tutorials anybody can direct me too.

Again, thanks for everybody's help and I look forward to getting this thing on the road!

 

as far as the connector goes bike was running at one time. It is possible po could not get it restarted one spring and when he pulled the connector it broke and he repaired it with the incorrect connector and by the diagram in the manuals.
I had to replace a connector to tci because when I pulled it out it crumbled.
the black white wire is what shuts down the tci. could be the tci is starting to fail or side stand issues.
I think that a shop would disconnect this wire to trouble shoot a non starting bike then find the issue.

the side stand wire is buried under the motor and goes through a few clips on my 550 I have to remove the lower rear fender to get to the connector to unplug it.
then ohm it out.

could be you have a clutch switch issue too. you can disconnect the clutch switch in the headlight bucket then the bike will only start in neutral.
with a disconnected switch the bike will not start in gear when you pull in the clutch lever. with switch disconnected you can test the switch with an ohm meter or continuity test.

 

The picture you posted earlier should bypass the side stand switch, however that doesn't mean the side stand relay is energizing and opening the set of normally closed contacts that disable the TCI by grounding the B/W wire. You can also disable the safety circuit by simply removing the side stand relay, which has the same effect as disconnecting the B/W wire. The ignition cutoff for a working bike is "In neutral OR side stand up" to enable the TCI to spark. The starter cutoff for a working bike is "In neutral OR in gear with the side stand up AND the clutch pulled in" to enable the starter.



Since you have found a couple of errors from the PO, I would also look into whether even the correct relays are installed in the correct location. They are all keyed the same and can inadvertently be installed in the wrong location. You may also want to look inside the head light assembly just to be sure the diode block is present as they have been known to be missing when PO's attempt to bypass portions of the safety circuit. The diode block is needed for both the head light relay and the side stand relay to function normally.

The head light relay (yellow dot) is a standard relay with an internal diode inside it to make it a latching relay. A working charging system is needed for it to energize and latch closed until power is removed. You have verified the charging system so a good place to start would be to make sure the relays are installed in the correct location.


From this thread:

https://www.xjbikes.com/forums/threads/the-ultimate-relay-switch-sensor-and-diodes-guide.27543/

XJ650RJ Seca and XJ750 Euro models:

NOTE: according to the factory XJ650RJ Seca service manual supplement, both the headlight relay and the sidestand relay are under the tank---this is wrong!

It also shows that the ignition cut-off relay is below the TCI?---this is also wrong!

Flasher: near the steering headpipe, on right side frame rail, under the right side ignition coil.
Flasher canceller: under the rear of gas tank.
Starter motor solenoid/relay: on right hand side, attached to and behind the battery box.
Starter/Ignition cut-off relay (no color): on 650RJ and 650 Euro models, located behind self-canceller, under rear of tank (note: the drawing and the description in the service manual is wrong).
Sidestand (kickstand) relay (blue): behind the flasher relay, under the front of the tank.
Headlight relay (yellow): behind the left frame side cover, on the plastic regulator-rectifier mounting plate. (note: the drawing and the description in the service manual is wrong).
Diode block: inside the headlight housing.
Neutral switch: in a hole in the bottom of the crankcase, just "outside" of the oil pan, on the bottom of the engine, up inside a recessed "well".

Good to hear the TCI's were not damaged.

 

This is on the XJ700 with both the caliper and master cylinder. It has some really good info with pics and may be similar enough to get you going

https://www.xjbikes.com/forums/threads/1985-86-xj700-caliper-rebuild.118121/page-2

I suspect your assumption is correct - and I bet he never joined XJbikes either to get some help.

 

I bought a used sidestand switch and before I hooked it up I noticed that one of the tongs to a GREEN wire is missing. There is only the Blue wire with a yellow stripe and the Black wire. There should be a third GREEN wire but I don't see it anywhere on the bike. Could this be the answer to all my electrical problems? Also, the back brake switch does not work and I still have yet to fix the front brake. All of these electrical issues are waaaaaay above my head so please bare with me as I try and figure all of this stuff out. Thanks.

 

Could you explain this to me. When I disconnect the B/W wire does that mean the TCI is NOT working?

 

So I think you are saying that the new (used) switch has an extra green wire - it should be G/L (green / blue tracer). If that is the case it is a switch from a bike that utilizes the computer monitoring system, and the switch uses an extra set of contacts to report the status of the side stand to the computer. It should work OK as long as the connector and wire length are compatible.

If disconnecting the B/W wire to the TCI results in a change of no spark to spark when the bike is in a condition that is considered safe to enable the ignition, then that means the safety circuit for the ignition cutoff is defective. The TCI should be active with either the bike in neutral OR with the side stand up. Typically, a non functioning ignition cutoff safety circuit is caused by a defective side stand switch, neutral switch, side stand relay, diode block, or wiring.

XJ550H will comment again on your question, but I think I remember him posting something about a TCI that acted a bit strange with the B/W wire connected and a working ignition cutoff safety circuit.

 

there have a handful of members here who could only get their bikes started by disconnecting this wire and stating all other safety systems were working,
I have a tci which starts and runs my 550 when black/white wire is disconnected. runs well . connect b/w wire bike does not run.
swap in my other tci with b/w wire connected bike runs as it should.

if all circuits are operating as they should , and with the several 550 TCI's I Have are working correctly with the B/W wire connected except the 1 unit which runs the bike only with the B/W wire disconnected.

this leads me to the opinion that the circuit in the black box (tci) connected to the black/white wire has an issue for this 1 tci.
the TCI works for ignition control but not for safety circuit. so it has failed for that circuit and may be on its way out for ignition control as well

does this mean the tci will fail for ignition or is the first sign of complete failure I can not say for sure until that tci fails. I do run the tci in my bike still and carry a spare.​

 

I guess I should ask what is the purpose of the B/W wire if all the safety systems work in the first place?

Also, I forgot to mention that the tail light is not working either. So, the switch that connects to the back brake that I mentioned earlier is not working could very well be fine and it's the connection to the tail light that isn't working properly.

So as it stands, the headlight and taillight does not turn on when the bike fires up. The side stand switch is not attached and the harness that the sidestand switch fits into is missing the green wire. And the bike only works if the B/W wire is disconnected. Left and right turn signals work fine, so does the horn. Instrument cluster works well too.

 

the B/w wire is what shuts down the tci if you deploy the sidestand when riding and keeps you from leaving side stand down and putting bike in gear and riding away into a bad left hand turn.
works nice as a kill switch too pull up and park bike deploy sidestand , bike turns off. then turn the key.



B/W wire. I think it is a service wire as in the mechanic at Yamaha unplugs it first when told bike has a no spark condition. if bike runs then he looks at the side stand switch and relay. on xj550s the relay is under the seat and is easy to remove on most other bikes it is under gas tank.
the side stand wire is run under motor and connector is behind lower rear fender and may require removal of lower fender.

so a 30 second check or remove gas tank or rear fender

 

Ah got it. I was under the impression that when you disconnect the B/W wire the TCI will not work at all and that the bike was just working on it's own in some other way or another. A little confused, sorry.

With all this information I'll do my best to try and figure this whole thing out. Thanks everybody.

 

The tail light and the brake light should work with just the key on - the bike does not have to be running.

The head light does need the bike running or at least the alternator to spin fast enough to produce enough voltage to energize the head light relay at which point it will latch and the head light will stay on until the key is turned off.

Did you verify the correct relays are installed for the head light relay and side stand relay as suggested earlier?