Relays & Spark to Plugs - '82 XJ750J Maxim

1982 XJ750J Maxim USA Model

I have 2 relays which are located:

Relay mounted above carbs/airbox boots on a "T" bracket:
4H7-01 Omron ( no marking )

Relay mounted under TCI box of left side:
408-00 Omron ( Blue marking )

One is the sidestand relay & the other is igntion cut-off relay.

When these 2 relays are in this position, the bike is not producing any spark.

If I reversed these 2 relays, then I get spark to all 4 plugs.

So here is my question, can someone confirmed which relay is which or which area that the relays plug into is which....???

Can I ruin these relays by having them reversed ??

When the 2 relays are plugged in as described above, the bike will crank accordingly to the book but no spark to the plug.

1. the transmission is in neutral ( neutral light is on )

or

2. the clutch lever is pulled to the handlebar ( the clutch switch is on ) & the sidestand is up ( the sidestand switch is on ).


When I switch the 2 relays around, the bike will crank & produce spark to all 4 plugs, accordingly to #1 but not to #2....

Is my starting cut-off relay possible faulty, & do I have these relays in the correct position ?

Can someone who has an 1982 XJ750J Maxim....not Seca.....please confirm their relay positions, the stamping on the relay, & the location of these 2 relays.....

Thanks in Advance

 

Anyone have any suggestions ????

Come on, all you 1982 XJ750J Maxim owners.....

 

Not a 750 Max owner but I'm sure I could help you muddle through this if I had my book handy (which won't be until tomorrow night, got class tonight). We can test the relays and see if they are working. Once this is done, we look to see if the right voltages are getting to where they are intended.
I gotta figure out how to make those cool little diagrams with ASCII characters like Rick-O-Matic does.

 

Thanks Robert....get back if you can....

is there any 1982 XJ750J Maxim owners...who can lift their tank up real quick & take a peek at the relay & the one under the left side cover.....

Please .....?????

Thanks in advance...

 

Ok I Just went out to the shop and checked two of my 750's. The relay with the blue dot is supposed to be under the LH side cover. I am looking at the wire diagram right now and I see that one relay has a diode built in and there is a whole test procedure to test it out. I would bet there is a way you could jump it out to get the bike running.

MN

 

Mn-Maxim,

Is the relay under the left side cover the one with the blue marking on it ????

...it is located just below the the IC ignitor.....

The other relay ( ignition cut-off relay - no marking ) is located under the back part of the gas tank just ahead of the bolt to remove the gas tank....the flasher cancelling unit is there as well....

Can you take a look at these 2 relays for me & indicate which relay is where ( with marking ), & the number stamped on the relay....it would be much appreciated.....

Thanks in advance.....

 

your relays are in the right place. You'll need to bypass the relay under the TCI to make that bike run. I can get you those numbers tomorrow. I'm sure Rick will pop in here with the info you need to troubleshoot that relay.

MN

 

Yes, my relay with the blue marking ( sidestand relay 4U8-00 ) is located under the IC ignitor......

The other relay with no marking ( ignition cut-off relay 4H7-01 ) is located under the tank behind the flasher self cancelling unit )....

I suspect now one of these or both relays are bad......

I am getting no spark to the plugs.....

Chacal or Rick-o- Matic.......help....any suggestions ????

Thanks

 

Starter/Ignition Cut-Off ("clutch-in-neutral") Relay:

NOTE: all XJ700 models and XJ750-X models use a consolidated relay assembly (mounted under and to the rear of the fuel tank, on the wishbone frame triple-tube joint) which combines the turn signal flasher, the turn signal canceller relay unit, and the starter circuit cut-off relay.

Location:
- on all 1981-84 XJ750 Maxim/Midnight Maxim/Seca models: under the gas tank, in-between the frame tubes, on a welded bracket just behind the flasher self-canceller relay.


Identification:
- on all models except XJ700 or XJ750-X models:
- small metal (original) or plastic (replacement) "cube" relay, inked 4H7-00, 4H7-01, or 12R-01 on the top face.
- has no colored paint mark on the bottom terminal connector block.
- sometimes labelled or described in manuals and diagrams as a "clutch switch unit", a "neutral safety relay", or an "ignition cut-off" relay.
- normally open; has an internal diode.
- plugs into a connector shell which has the following set of wires going to it:

Harness connector wire colors:
- on all XJ550 all models, XJ650 all models, XJ750 all non-X models, and XJ1100 models:
* Red wire with white tracer stripe
* another Red wire with white tracer stripe
* Black wire with yellow tracer stripe
* solid Light blue (sky blue) wire

- on all XJ900 models:
* Red wire with white tracer stripe
* another Red wire with white tracer stripe
* Black wire with yellow tracer stripe
* solid Light blue (sky blue) wire
* another solid Light blue (sky blue) wire
* White wire with red tracer stripe



Sidestand (kickstand) Relay:

Location:
- on all 1982-84 XJ750 Maxim/Midnight Maxim models: under the left frame side cover, on the plastic regulator-rectifier mounting plate.

Identification:
- small metal (original) or plastic (replacement) "cube" relay, inked 4U8-00, 4U8-01, or 4U8-02 on the top face.
- has a blue paint mark or blue locking tab shroud on the bottom of it.
- normally closed; does not have an internal diode.
- plugs into a connector shell which has the following set of wires going to it:

Harness connector wire colors:
- on all XJ550, all 1982-84 XJ650, XJ700, XJ750 models, all XJ900, and XJ1100 models:
* Red wire with white tracer stripe
* Black wire with white tracer stripe
* Blue wire with yellow tracer stripe
* solid Black wire




Electrical System Diode Block:

Location:
- on all 1982 XJ750 Maxim and all XJ1100 models: uses a single diode, sheathed inside a clear sleeve, located just outside the main wiring harness bundlke, in the area just behind the fuel tank.

Identification:
- on all 1982 XJ750 Maxim and all XJ1100 models: a single diode sheathed within a clear plastic protector sleeve. The diode has bare wires on each end, terminated with bullet connectors.

Harness connector wire colors:
- on all 1982 XJ750 Maxim models: a single diode sheathed within a clear plastic protector sleeve. The diode has bare wires on each end, terminated with bullet connectors, that attach to a solid sky blue wire on one end, and into a blue wire with a yellow tracer stripe on the other end.



BY-PASSING SWITCHES AND RELAYS:

How to bypass various relays: first of all, our advice is DON'T. The relays and switches are there for a reason....your safety, to prevent "mistakes" from turning into "disasters".......so our recommendation is to just leave the system as it is, and replace any components that fail. However, for failure testing purposes, it may be necessary to temporarily "by-pass" certain components, thus elminating their functionality from the circuit, to see if they are the source of whatever problem is occurring.


Sidestand (kickstand) switch:
- twist the two (or three, depending on the model) wires together and ground them. Grounding the wires is the only way to complete the circuit that activates the sidestand switch relay.

Sidestand (kickstand) relay:
- unplug the safety relay which disables the whole bloody mess but DO NOT leave it that way, fix it right!

Starting/Igntion cut-off relay:
- unplug the safety relay which disables the whole bloody mess but DO NOT leave it that way, fix it right!



TESTING SENSORS, SWITCHES, AND RELAYS:

Sidestand (kickstand) switch:
* continuity test: circuit should be complete (0 ohms) when switch "plunger" is extended and circuit should be incomplete (infinite ohms) when the plunger is pushed in.

Sidestand (kickstand) relay:
- due to many variations in design and the need for visual reference, you should check your service manual for the proper testing procedures.

Starting/Igntion cut-off relay:
- due to many variations in design and the need for visual reference, you should check your service manual for the proper testing procedures.

Diodes:
- due to many variations in design and the need for visual reference, you should check your service manual for the proper testing procedures. Basically, diodes only allow current to flow through a circuit in one direction only; thus a diode, when tested with a continuity meter, should show continuity when checked with the probes placed in one orientation, and then when the orientation of the probe leads are reversed, no continuity (no circuit).

 

Thank you very much for the info...... I believe my ignition cut-off relay may have a bad diode in it......

I may disect ( open up ) this relay to see what is going on with it.....

I dont believe the resistance is testing out per the ohms test when disconnected & connected to a battery & testing the posts on the relays per the manual

Look for an order real soon.....lol....or I find someone who has an extra relay.....

& your deluxe petcock rebuild kit that I bought from you for my 1982 XJ750J Maxim worked flawlessly....I saw an earlier post on this discussion

 

BEWARE the Yamaha manuals (or, even worse, the Haynes) in regards to the safety relay checking procedures. Somewhere, somehow, something got messed up (or just too crammed together) to make much real sense out the diagrams (and I haynes, some of the diagrams are mis-labelled, etc.).

 

i will be looking for this electrical system diode tomorrow. I suspect that may be a problem also..

If it is bad....would that cause no spark to all plugs ????

 

If the safety relays are not able to operate properly (for whatever reason), then one effect is that you get no spark, since the safety relays tend to perform their electrical magic via grounding of the TCI unit.....thus no spark!

 

So if you were to pull the plug on the ignition cut out relay, the TCI would not be grounded and the plugs should get spark?. Maybe when he swaps relays the good relay lets the TCI spark. Wish I could make sence of this wire diagram.

MN

 

When I swap the 2 relays....the sidestand stand relay where the ignition cut-off goes, & I put the ignition relay where the sidestand relays, I got spark....for a while.....

Now I get no spark at all either way.......so I put the ignition cut-off relay back where it was ( under tank opposite flasher cancelling unit on the wishbone )& the sidestand relay back where it was ( under left cover, under IC ignitor )...

I will pursue buying 2 new relays......I may have a bad electrical system diode as well......damn if I can find this diode....I have looked everywhere for it.....

 

Try looking for the "Sky Blue" wire with a bullet style end terminal.....the sky blue wire leads to the diode......it's the only place on the bike that the sky blue wire is used............it's a light, pale, baby blue color, runs between the neutral safety switch (look near the TCI connectors), the neutral safety switch relay, and also runs up to the gauge cluster.

 

What if you removed components from the interlock system. Can the bike be re wired or bypass some stuff to get bike to run?