'97 RSTC Speedo & Odo Shut Off When Clutch is Pulled In

[mechsafe]

Thanks in advance for any help in solving this mystery.  A few weeks ago, my speedometer started going to zero and the digital (LCD)  odometer goes blank whenever the clutch clutch lever is pulled in far enough to open the clutch interlock switch. I first noticed it when shifting and thought voltage was dropping excessively when the engine RPMs dropped, but there are no other indications of low voltage.  It seems to be a direct result of the clutch interlock switch opening.

mechsafe

[Marcarl]

8 hours ago, mechsafe said:

Thanks in advance for any help in solving this mystery.  A few weeks ago, my speedometer started going to zero and the digital (LCD)  odometer goes blank whenever the clutch clutch lever is pulled in far enough to open the clutch interlock switch. I first noticed it when shifting and thought voltage was dropping excessively when the engine RPMs dropped, but there are no other indications of low voltage.  It seems to be a direct result of the clutch interlock switch opening.

mechsafe

I would start with cleaning the switch.

[saddlebum]

Also study your schematics and see if there is any commonality with the wiring circuits of the speedometer and interlock switch. You may even have a situation were the interlock switch signal is back feeding through the speedometer signal canceling out the speed signal. This could be the result of a dirty or open circuit in the interlock circuit resulting in currant taking an alternate path through the speedometer circuit canceling out the speedometer. 

[RDawson]

Check grounds. A loose or dirty ground somewhere can have other circuits chasing ground through there. Check all safety switches and wiring on the start circuit, clutch, neutral safety switch, side stand. The clutch switch on the Venture has two sets of contacts, pulling the clutch closes the start circuit and opens the cruise control contacts.