I/S No Clock or Radio Display. Just Fuel gauge FIXED

[Jersey]

FIXED

I had to replace the Main Harness to resolve the issue.  Apparently, there was something in the original harness that inhibited the Radio from talking to the Dash.  The Radio uses an SPI protocol (90's era).  Something in the harness seemed to affect the Clock and Data lines.  This could be as simple as a hairline crack in the wiring insulation and a bit of moisture... I don't know.  The good news is Freya will ride again with TUNES!!

Really want to thank everyone for their ideas and recommendations.  Special shout out to Dave Tillis who was kind enough to lend me his bike for test comparison purposes.
Cheers,
Jersey

--------------------------------------------
I am a little stuck and could use some ideas.  Normal thing, radio was working, etc.  Went out to check the bike and no Radio or Clock Display.  Here's what I've done:

-Did Splice Block mod.
-All Fuses checkout fine.
-Battery is new and checks fine
-Audio Relay Fine. (voltage checks)

Haven't started checking the two radio plugs yet, next up on the list.

Thanks ahead of time
Jersey

BTW, does anyone have an extra working radio they don't need?

UPDATE:
-Cleaned and verified Radio wiring connectors (20p, 9pin, etc)
-Checked continuity of Main Harness (IAW Svc Manual Section 20)

This weekend I'll be testing the radios on another Interstate to re-verify they are working.  Will also give me an opportunity to take voltage measurements of a working OEM harness to help in the investigation.
-Radio and Display both verified working correctly... Dave T brought his I/S down today and we swapped these in to verify operational.

[Bagger John - #3785]

Check those plugs (under the seat). I've found corrosion on the radio connections of one of my Interstates - which was ridden in the rain from time to time.

A little pro tip:

Us electronic repair types like to use a formulation called DeOxit D5-100L for cleaning and protecting plug pins, terminals and whatnot. I prefer it over dielectric grease, which can actually contribute to the problem in certain circumstances.

[mustang071965]

Under the battery case is a orange plug block. It is corroded or lose. Pull battery take cap off plug clean with electrical cleaner put cap back on and reseal with tape

[Jims99]

A little pro tip:

Us electronic repair types like to use a formulation called DeOxit D5-100L for cleaning and protecting plug pins, terminals and whatnot. I prefer it over dielectric grease, which can actually contribute to the problem in certain circumstances.

[/quote]
Tried looking this up, there’s quite a few. Could you add a picture of what you use? Thanks

[Savage]

This formulation, called Stabilant-22, is used on connections in the Nuclear industry.
I have been using it with excellent results:

[Bagger John - #3785]

A little pro tip:

Us electronic repair types like to use a formulation called DeOxit D5-100L for cleaning and protecting plug pins, terminals and whatnot. I prefer it over dielectric grease, which can actually contribute to the problem in certain circumstances.

Tried looking this up, there’s quite a few. Could you add a picture of what you use? Thanks

My bad - the full strength stuff is "D100-L".

Here's a link to Caig Labs product specs: https://caig.com/product/deoxit-d100l-25c/

[Bighead]

Or your alternator could be taking a dump

[gordonv]

If it's the main wire harness block under the battery, then I have a how-to Doc on doing it.

Just send me an email, and I'll forward it.

[Jersey]

If it's the main wire harness block under the battery, then I have a how-to Doc on doing it.

Just send me an email, and I'll forward it.

Sent an email. Thanks!

[Jersey]

Gave Up. Replacing the Main Harness.  Will be here in a few days and hopefully all will be fixed.

As mentioned in the original posting, Dave T was kind enough to ride down for the day to help troubleshoot and do some bike comparisons with his I/S. This was great because I could verify both the Radio and Dash are working fine! The problem is clearly with the harnesses or thereabouts.  In the end I checked:
-continuity of everything
-resistance of each wire to gnd & pwr and every other wire I could find... all clean
-inspected each terminal for corrosion, physical integrity, etc.
-verified every Relay, diode, & fuse.  
-Mod'd the Splice Block under the Battery (BTW, there's a SECOND SPLICE BLOCK Right Side under the fuel tank)
-prayed, swore, sighed, had a beer, admitted defeat, bought a replacement.

Thank you for all the help and advice.  That's what makes this site great.

Jersey

[Avanti]

What about the Audio Switch Panel? Have you had that monster apart and checked all the contacts?

[Avanti]

That is great that you are up and running again. Very nice for friends to jump in and lend a hand or in this case a complete Valkyrie.

[strawbobrob]

I have had the same problem with my 99 IS.  I did not want to hear this outcome—to replace the entire harness!  How long did that take you, and were you ever concerned you’d get halfway through and get lost on routing or connections?

[Jersey]

I have had the same problem with my 99 IS.  I did not want to hear this outcome—to replace the entire harness!  How long did that take you, and were you ever concerned you’d get halfway through and get lost on routing or connections?

Overall, it's an easy job if you're just replacing the harness.  May want to take a bunch of pictures in different areas to remember which connectors (wire colors) go into which location (Coil terminals!)

The easiest part is reinstalling the replacement harness.  the Hardest part is finding a place to NEATLY storing the nuts/bolts.  I labelled ziplock backs to hold different things for each area.

Used harnesses are easy to come by for about $20-30 ea.  Checkout Pinwall.

If you're comfortable doing normal stuff, then this should be easy.

Hope this helps!
Jersey

[gordonv]

The easiest part is reinstalling the replacement harness.  the Hardest part is finding a place to NEATLY storing the nuts/bolts.  I labelled ziplock backs to hold different things for each area.

How about empty egg crates?