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Discussion Starter #1
Hey Guys I have a 2003 1300 and tonight on my ride my speedometer quit working. Everything else worked though the back lighting all the indicators. The trip meter did stop counting. It just froze at 46.6 miles on trip A. Can you guys think of anything else it might be before I go order one? Also has anyone had any experience replacing one. Is this something where I will need to plan to refill coolant and Oil?
 

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1300 rarely has a VSS failure.

You can verify +12v and Ground at the VSS connector..
Check for +5 volt pulses (sometimes +3.7 volt pulses)coming from the VSS.
The VSS is high on the rear of the crankcase just inboard of the cross shaft.
No oil, no coolant.

The pigtail faces down.
 

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Discussion Starter #3
Alright so I don't have this inspection adapter which seems pretty handy for this job at the moment any suggestions on how to go about tapping into these lines without splicing into the wires?
 

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Check the Green speedo connectors under the tank.

I did not have an adapter either.
2010 - I do not remember the details, but counting pulses per wheel revolution was my intent.
You could check at the Green speedo connectors.
Check the connector at the crankcase cover, could be a regular connector where you can push a wire into terminals.
Needle into a wire is another choice.
https://www.youtube.com/embed/eAh4Y9piRhs
 

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Discussion Starter #5
Check the Green speedo connectors under the tank.

I did not have an adapter either.
2010 - I do not remember the details, but counting pulses per wheel revolution was my intent.
You could check at the Green speedo connectors.
Check the connector at the crankcase cover, could be a regular connector where you can push a wire into terminals.
Needle into a wire is another choice.
https://www.youtube.com/embed/eAh4Y9piRhs
He Hans Sp Just a quick Follow up on this I've done a little more digging into my bike. I'm looking at the three pin plug over the crank case. Per your diagram above the white wire should be in the center of the plug and per you notes on the other page should be the 5 volt signal wire but on my bike the white wire is on one of the outside pins pins of the plug. I will attach a picture to show you what I'm talking about.

Now I think the side of that connector with the pink wire is what runs to the sensor and the other end runs to the Chassis/ECM. I disconnected that plug and used a test light hooked on a ground. I got a positive signal off of the 2 outside pins (the white one and the black and brown one). I didn't get a positive signal on the middle green one but when I hooked my test light to either one of the outside positive pins and then hit the middle green pin the test light lit up indicating that I hit a ground.

Does that seam right that 2 of the 3 pins on the chassis side are reading positive? Does that indicate that there is a short somewhere?
 

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A schematic is NOT specific about wire position.

1800 shows Pink at VSS so the 1300 schematic I used could have used the incorrect color.

if you have battery voltage(abt 12 volts) on the Bl/Br then re-connect the connector and look for pulses on the White or Pink wire.
 

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Discussion Starter #7 (Edited)
OK So I was able to get my hands on some extra 3 Pin terminals and made my own inspection harness. I put the bike on the stand and confirmed the 12v, ground, and 5v reference. I put my test light on the 5v reference and spun the rear tire while in neutral with the key on and only got a solid light. It never pulsed. I do want to reiterate my concern that the 5v Signal is coming from the ECM Side of the harness and not the sensor side of the harness. Is that supposed to be correct?
 

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Discussion Starter #8
To Follow up I just went back out to do some additional testing with the test light and now it seems that that 5v signal from the ECM goes away when I plug the harness into the speed sensor plug. and when I spin the wheel I get zero pulsing the 12 volt wire is staying strong though.

This is strange though because the 5v was lighting up the test light earlier today just not pulsing.

Earlier today I had my test light clamped onto a ground bolt. so this evening I decided to put the clamp on a probe and probe the ground wire on the harness. My Test light let for a little while and then stopped lighting up so I moved the ground clamp back to the ground bolt and still no light on the 5v signal. I tested on the 12 vold and was able to confirm that the test light was still good.

I've attached a picture of my set up how I'm tapping in. I'm using the yellow barrel connectors as ports so that i can probe each wire. I tested each one for continuity and they are all good.

I'm At an absolute loss here.
 

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The VSS output may have a pull-up resistor from +5v.
An output transistor in the VSS is switched on and Off.
When Output transistor is ON, the output is Low(near zero)
When the Output transistor is OFF, the output is high(near +5v)
Output voltage in reference to Ground wire.
My guess of the way it works.

A output transistor or kept ON by by another component would keep the transistor ON.. No pulses.
A shorted transistor could keep the output low - no pulses.

With +12v and Ground to the VSS,
The output lead to a light with the other lead going to +5v(preferred) or +12v should be pulsing when wheel turned.

I used leds for visual testing and the voltmeter for voltage.
A basic VSS schematic attached.

Verify tests again. Many VSS have failed so no longer unusual.
 

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Discussion Starter #10
The VSS output may have a pull-up resistor from +5v.
An output transistor in the VSS is switched on and Off.
When Output transistor is ON, the output is Low(near zero)
When the Output transistor is OFF, the output is high(near +5v)
Output voltage in reference to Ground wire.
My guess of the way it works.

A output transistor or kept ON by by another component would keep the transistor ON.. No pulses.
A shorted transistor could keep the output low - no pulses.

With +12v and Ground to the VSS,
The output lead to a light with the other lead going to +5v(preferred) or +12v should be pulsing when wheel turned.

I used leds for visual testing and the voltmeter for voltage.
A basic VSS schematic attached.

Verify tests again. Many VSS have failed so no longer unusual.
Its Sitting at 4.71v consistently. there is no change as I roll the rear wheel in neutral.
 

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Replace VSS 2003 1300S
10 SENSOR ASSY., SPEED 37700-MCV-003 In Stock $118.02 $91.33 Plus s/h

Check other places, may find a few $$$ less.
Highly over priced it would seem for a magnet, Hall effect device, IC chip and a housing.

https://www.hondapartshouse.com/oemparts/p/honda/37700-mcv-003/sensor-assy-speed
SENSOR ASSY., SPEED 37700-MCV-003 Your Price: $86.15 plus s/h

Less cost and free shipping
https://www.ebay.com/itm/Honda-Motor-37700-MCV-003-Honda-Speedometer-Speed-Sensor-VTX-1300-1800-/143405855353?_trksid=p2349526.m4383.l4275.c10#viTabs_0
 

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Discussion Starter #12
Well She put up one hell of a fight. Even after you drop the Coolant overflow tank that sensor bolts aren't the easiest to get on but I got it out. I found a used speed sensor off of Ebay for $40.00 with shipping. that came in last weekend but I made the mistake of ordering the new O-Ring from Honda Direct line that place takes for ever to ship a part out. I seriously don't see how they can still be in business. anyways that came in this past Thursday so when I got home from work today I was on a mission. I got the new to me sensor installed with the new o-ring and got most everything put back together pretty much with the exception of the crank case cover and decided to start it up and test it out. I got it off the jack and ready to roll and the Damned Battery was to weak to start it. What an absolute [email protected]<k Block. So I got the bike jumped of and decided I wasn't even going to wait long enough to put the seat back on and road her Bare Backed once around the neighborhood and Glory Be I have a speedometer again and my Mileage counter is counting again. Now I see there is a guy on Facebook who can replace your LCD display on you speedometer if its all hazy like mine is so I think I'm going to take him up on it.
 
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