Headlight functional without Headlamp relay, and shuts off when plugging it back in.

Alright,

To summarize a very long story, the bike always started and ran fine with existing headlamp relay.

Headlamp knocked off working low and high beam.

I unplugged the relay, started the bike headlamp WORKS, the red input power wire is not shorted to blue output wire (no continuity or voltage). The blue wire doesn't have voltage when tested against ground. Furthermore, the headlamp will not turn on with key switch, but only after the bike is running. Which seems to me someone INTENTIONALLY cut and joined the blue wire going to lo/hi switch to the rectifier circuit (perhaps to the wire allocated for the headlamp relay.

If I plug the headlamp relay back into its connector with bike running and headlamp on, the bike shuts off and doesn’t restart. So what the hell.

Could an internal short in relay knock out the whole ignition system (Bike always ran fine with it installed before?) What circuit could the previous owner spliced into to get rectified voltage over the fuel tank besides the rectifier wire for the headlamp relay?

If the blue wire magically burnt off completely and fused to the rectifier wire this would be the fastest short I have ever seen.

 

The headlight will only light with the bike running. This allows all voltage to go into the starting circuit.

 

Right, but relay is unplugged. So how does the rectifier switch the headlamp relay? Why when I plug in headlamp relay the bike shuts off.

 

What bike are we talking about here?
For example, the 750 Maxim doesn't have a relay

 

I am sorry it is an 1983 XJ650.

 

I'm not sure what this statement means, "Headlamp knocked off working low and high beam."

Are you sure the relay you're plugging and unplugging is the headlamp relay? The Haynes manual says wiring of the headlight relay for your bike is White, Black, Blue/Black, and Red/Yellow.

 

your headlight relay closes when motor starts or spins fast enough to trigger relay


The Ultimate Relay, Switch, Sensor, and Diodes Guide

location
- on all XJ650 Maxim/Midnight Maxim/RJ Seca models: behind left side cover, below the TCI and Regulator-Rectifier unit.

Identification:
- small metal "cube" relay, inked 3H5-00 on the top face.
- has a yellow (yellow) paint mark on the bottom terminal connector block.
- 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 (except Turbo):
* Blue wire with black tracer stripe
* solid White wire
* Red wire with yellow tracer stripe
* solid Black wire

 

Does anyone know if the Canadian 1983 Xj650 has a headlamp relay at all. My headlamp wire is a blue/black stripe that has continuity with rear park lamp.

 

Basically the 6 pin connector, in the headlamp that connects to the lo/hi selector switch has a Blue wire with black stripe, I can trace it back right to the rear park lamp without a relay in the circuit. If someone removed the headlamp relay, it would have to be pretty slick and actually replaced the wires and the terminals fully.

 

it should have a relay and should not be running from the tail light wire

they would have only had to replace 1 wire i will look

the color is correct for the hilo switch a

 

is there a relay on the rectifier panal behind left side cover?

I can not find a canada wiring diagram

 

Thanks for the reply. No there are no other relays with metal cover anywhere else except the starting circuit cutoff relay. Is the headlight relay supposed to be on the rectifer/TCI side? I would like to wire it back in.

 

I've been doing a deepish dive into xj650s ... you know... cause it's Saturday night and I have no life...

the 1983 XJ650 is called a xj650k (news to me, maybe not you)

I've also found information at a website I haven't seen referenced here before, and I'm wondering if that's on purpose.... so I won't mention here, but maybe a PM is more appropriate

regardless, I haven't found an answer to the question posed here, but wow.... so much info...

 

all power wires will have continuity to each other with key in on position.

that is a nice drawing it is a bike sold in the euro /UK market as it shows an on off switch for the headlights.

it could be that SM85 has a euro market bike. so he should do a vin check to confirm his bike.
that can be done in this thread it has a quick find link or can be done by reading and pen and paper
TECH TOPIC: Model ID and VIN's

as far as headlight relays and all the other relays accurate locations, id of the relay and its connection wires is found here
The Ultimate Relay, Switch, Sensor, and Diodes Guide as well as charging system info and ignition system specs and info.

there is always reading
The Information Overload Hour

there is very little info that can not be found here a very good source of info can be found in the
XJ4Ever - Supporting Vendor

many threads on the bikes as well as his catalogs which are also full of information.

we are always interested in other sites in our quest for information, it is not against the rules to post them

there are sites for the maxim X http://www.maxim-x.com/ that offer more info because it is a dedicated site to the X there was a XS/XJ 1100 site but it sees to be closed to new members and possiblyy been abandoned by its owner. https://www.xs11.com/

 

Good news guys!
I found the location of the headlamp relay, it is supposed to be by the rectifer/voltage reg. But the pigtail harness was cut out and wired directly to tail lights. Should be fixable now with a 12v automotive relay for now until I can get a wiring harness.

Another problem I had is that I was unplugging the starting system cut off relay. When I would plug it in the bike would shutoff. When I tested the relay I have continuity between two terminals, can anyone tell me if this relay is supposed to be normally closed or open? Because I think the relay may be shorting interally and grounding my ignition circuit.

 

I think you're still mixing up relays. The starter circuit cutout relay never prevents the bike from running, it only prevents engaging the starter. The sidestand relay, on the other hand, does prevent the bike from running, and it is normally closed. If the sidestand is down, the bike must be in neutral for this relay to open. Test it with 12V and a meter. Maybe you have a bad relay, or maybe you have bad wiring, or a bad neutral switch.

As for the headlight relay: it has a diode in it to keep it latched once it closes. If you replace it with a generic relay, that should work, I think... unless it ends up toggling on and off with the single phase pulsing output from the one white alternator wire. If you add a 1A diode externally from blue/black to white, with the anode on blue/black, then you'll have something that works like the original relay.

 

Is this the sidestand relay? I think it is, so bike is shutting down when I plug this in. This means I must have something wrong with kickstand switch/wiring or something else right?

 

The sidestand relay is the more forward one under the tank. Other than that, read what I already wrote above.

 

I think they look the same, but have a different part no?

 

location of relays
XJ650 Maxim and Midnight Maxim models:

Flasher: near the steering headpipe, on right side frame rail, under the right side ignition coil.
Flasher canceller: under the rear of gas tank, behind ignition coils
Starter motor solenoid/relay: on right hand side, attached to and behind the battery box.
Diode block: inside the headlight housing.
Starter/Ignition cut-off relay (no color): behind the turn signal self-canceller. (note: the drawing and the description in the service manual is wrong).
1980-81 Sidestand (kickstand) relay (blue): did not use.
1982-84 Sidestand (kickstand) relay (blue): frame bracket outbound of LH frame tube, just behind the left ignition coil.
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).
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".

 

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

 

The saga continues.

So now, if the bike is in neutral AND I put the sidestand down the bike shuts off. The bike will not start with the sidestand down. The safety relay clicks when sidestand is put down.

Now all of this worked fine before I rolled the bike into the garage to look at headlamp wiring. This is probally/most definitely the problem I encountered in the first post of this thread.

I have checked the sidestand switch, it is working and not shorted as in when you put the raise the stand or lower it, it has continuity and open circuit. I did not tamper with these circuits at all. I have also checked the neutral switch, it tests okay via the ultimate thread here on the forums, the green light illuminates in neutral and turns off when switching up or down in gear.

Worst thing is that I cannot find a wiring diagram that includes the sidestand. Is it supposed to be normally open or normally closed. The safety shutdown relay is clicking into an open position obviously to kill the ignition system.

 

the K simply means it’s a 1983

if you had just said you have an xj650K, we would have already known the year. Example....xj550j is a 1982 550 maxim; Xj900rk means 1983 Xj900 Seca, etc.......

 

The side stand switch is open when the side stand is down. Closed when it is up. If you have been doing things in the headlight bucket, you may have messed something up with the diode block that is in there. Also, are you sure you didn't swap any relays around while you had them out?

 

The only thing I unplugged in headlight bucket was the 6 pin for the lo-hi selector/turn signals. I however have gotten an XJ750 wiring diagram and it shows the sidestand relay and the sidestand switch. I see the diode in the circuit. Tonight, I unplugged my diode pack and tested them with diode testing function on DMM, then resistance testing the diode in both Forward Bias and Reverse. I am pretty sure the diode pack has clunked out (took off rubber cover and found corrosion, it looks like someone punctured it sometime in the past perhaps to test the diodes. If the diode is in a open broken circuit. Could this allow current from the neutral switch, or starting circuit cutoff relay to trip the sidestand relay open?

I made sure that the blue marked relay went back in the sidestand relay spot. The only other relay that looks like this is the starting circuit cutoff, which is black in color and right at where the tank clamps to frame.

 

750s and 650s have different side-stand switches and different diode blocks. Seems, from the number of mentions here, that the 650 diode blocks are more problematic, but that's just my impression.

If D2 in the 650 diode pack is bad, then that would prevent the neutral switch from being able to open the cutoff relay. You could try jumpering in a 1A diode from Blue/Yellow to Light Blue at the diode block, with the cathode (striped end) connected to Light Blue.

 

I was only able to track down a single 1A diode, around my small town.

Does anyone know for a good tested diode pack, or a new one? I cant find one on Forever XJ.

 

radio shack sells on line.

ebay sales
https://www.ebay.com/sch/resistorsandmore/m.html?item=173823671460&rt=nc&_trksid=p2047675.l2562

 

have you tested the neutral switch?

 

He said earlier that the neutral light was working correctly.

 

Hey guys, giving an update! It was the diode pack at fault. I replaced the diodes on the small PCB with 3A Diodes and a fresh 1watt 8.2OHM Resistor. Everything working good now! Thanks for your all your guys help!