Mystery on Solenoid

[Shaggyman]

2001 Pioneer 1200
This *thing* was on the solenoid, bridging the two small posts.
SOL THING.jpg
There is no continuity.
Markings on the black cylinder in the middle are:
LTh 05
1N5401
Runs fine (better actually) without it.
Rectifier? Resistor?
I have no clue, and the manual doesn't show it at all.
Anyone know what it is and it's function?

[Fairtax4me]

Its a diode for spark suppression when the solenoid coil is de-energized. There is a spike of voltage created in a magnetic coil as the magnetic field collapses, and that spike can cause arcing across the microswitches and burn the contacts.
The stripe end has to go towards the positive side.
Testing is done either with the Diode check function of a multimeter, or it can be tested with an ohmmeter usually set to the highest range. Touch one probe to each end and you should have a resistance reading one way. Reverse the probes and it should show O.L. or ~ resistance.

https://www.mouser.com/ProductDetail...1ByC6hIQItM%3D

[Shaggyman]

Thanks!
Perhaps added by a prior owner who was a lot more informed than I.
It showed no continuity either direction, but that was at the 200 Ohm position.Just checked it again at 2K Ohm and got expected continuity one way and open the other. (No diode test on my cheap meter)
I guess I'll put it back on for whatever protection it may provide.
Could that reverse spike go the other direction and fry the Neutral microswitch down the grounding side at the F/R selector if it were installed backwards?
I just replaced it due to the fuse blowing every time I tried to start...

[Fairtax4me]

No that would have been put on at the factory. Possible it is dead, they don't usually last forever. It does serve a purpose, and really should be replaced. Those switches cost a lot more than a $2 diode.

[Shaggyman]

Edited above.
Odd that the factory manual does't mention it at all.
Perhaps it regards it as an integral part of the solenoid.