An R+D Thread - Different instruments.

... I do have a complete loom - but it is attached to a brand new boxed set of kmh instruments. I'm reluctant to hack that apart. Maybe his Electric-ness @DEcosse knows what the spec's for said plug are.
I believe it is this one that mates to the one on the Main Harness:


- see page 5-8

Main_Harness_Speedo_Connector.jpg



Note that the image in the link does not reflect the actual part - see the product drawing (above) for confirmation

The Plug (Female Terminals) is 174047-2 (On the Main Harness) - on Left of drawing above.
The Cap (Male Terminals) is 175652-2 (on Speedo Sub-Harness) - on right of drawing above

Male Terminal Cap:

F5306319-02.jpg


In US available at Mouser -

(note that you also needs the terminals, available separately)


In Europe from RS - https://uk.rs-online.com/web/p/pcb-connector-housings/5306319/


Here are some Interconnect Diagrams I created:



Speed_Interconnect.jpg


(note interestingly that although there is a wire in the Main Harness Connector for the Illumination, it is unused on the Speedo Sub-Harness that I have on-hand)

It is VERY IMPORTANT to note that the OEM speedo put OUT a switched 12V on Pin 18 (B/Y) which is REQUIRED to drive the speed Sender - when installing an after-market Speedo Cluster this B/Y MUST be connected to a switched 12V source (i.e. connect it to Ignition Power since your after-market gauge will not have this provision)

See also these threads for more on the subject

Potential Replacement for failed instruments on Classics

Instrument Replacement
 

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I received a sub-harness from @Rocket Scientist along with a 'failed' set of Original Instruments to take a look to see if there was anything I could find:

Original analysis didn't show anything obvious on the board and without a schematic I was unable to do much real 'active' analysis;

However when I pulled out the harness to create the diagrams above, I did see this .............

Speedo_connector.jpg


^That is the one that mates to the main harness - NOT PRETTY!!
(on the mating side, the terminals looked clean however - interestingly there was evidence of dielectric grease on the mating side, but not the wire side)

I'm not sure if that had any bearing on the failure mode - I did not notice it when testing out the module.
I suspect not because I know instrument replacement has resolved this issue (and presumably the original sub-harness was re-used)
Whether or not it contributed to the instrument hard-failure remains open however ............

I will try to clean it up and re-test the module I have to see if it makes difference (again, suspect it won't - my power connections were clipped directly to the wires via positaps )
 
OK - Here's an important-ish note.

GET AN INSTRUMENT THAT HAS DECENT DOCUMENTATION.

This cheepo off ebay is a bit lacking. For example it says it will switch kmh/mph but does not say how - not exactly.
And the wiring colours are all over the place - no winging it, or something will smoke.
For example (reading between the lines) the speedo sensor supplied operates at 5V
I will eventually need to measure the voltage on wire "speedo out"

I will be initially testing WITHOUT connecting to the bike. When I know it all works - stage 2 begins.
This could be a while. Right now I lose dexterity after about an hour in the workshop (it's a bit too chilly still).

Speedo calibration will be a PITA with this cheepo as it does NOT have a self-teaching mode.
But the rolling circumference of the rear tyre needs to be input - plus the pulses per wheel revolution which (iirc @warp9.9 ) is 48 ticks.

@scot in exile - Take a browse at Motorcycle Gauges - not by any means the cheapest - but Jon only stocks what he believes in.
It might give you some ideas - Digital/analog - sizes etc. I would personally NOT go for ACEWELL - I have seen a few fail.
 
barbagris said:
I will eventually need to measure the voltage on wire "speedo out"
It's (nominal) 12V (might measure bit less but nominally that's the supply, NOT 5V)
 
This is amazing info to have. I bought my ‘05 last fall knowing the speedo was bad and have been waiting to order a new one, not knowing if I wanted to stay OE or aftermarket.
 
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