Modern Vespa

I've been lurking in the threads for weeks trying to fix my bike. I inherited this bike and it has sat for the better part of a year or two (at least). Ran great for one day fresh out of storage. The next day I got the dreaded tilt beeps and horns. First go around was 5 horns when trying to engage the lock. Changed the battery and then I get 1 horn then continuous beeps. Below is a video of the issue:

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Error goes away when I turn off the bike. Tilt lock will engage intermittently and I have to turn off bike then turn on to disengage. If I do not try to engage the lock, the bike is completely fine. I plan to run it that way, but I would like to fix should I ever want to use and for resale value down the road.

Reading pretty much every post, here is what I have tried:
-top off reservoir
-full tilt system bleed and fluid replace (all new fluid and kept full the entire time)
-cleaned speed sensor and inspected wires (looked intact)

My next thoughts to try:
-microswitch (can't find a good video or picture to diagnose)
-pressure switch (can't find a good video or picture to diagnose)

Complete newbie in cycles, but I am a diy guy and pretty handy. Any ideas or suggestions would be greatly appreciated

Can't help with your problem but check out this video it may help

Thanks for the reply. I saw that video but didn't seem to locate my exact code.

From user Mono a few years ago. You could just disable the tilt-lock. Tilt lock modification, or fix.

Service manual
https://www.manualslib.com/manual/1337951/Piaggio-Mp3-400-I-E.html

You may have seen this thread already, but just in case, it has allot of things to check for tilt-lock. Tilt Lock problems (red light+alarm)

Searching the internet for MP3 error codes there aren't any official websites or service manuals I can find.

Most of the stuff I can find revolves around
* Electrical system, battery or voltage regulator, fuses
* Gripper pads for the tilt mechanical lock worn down
* Mechanical malfunction of the tilt-lock (grip pads, hydraulic cylinder, fluids, or sensors.
* Tilt Lock pressure sensor How do I replace the tilt-lock pressure sensor

A couple years ago someone posted on the forum about a hidden adjustment screw down near the brakes of the front suspension. I recall it was related to the tilt-lock suspension and adjusting it helped. However I cannot find it anymore; hopefully someone else remembers and can post.

Hi mate,

I've been through all of this over the years, ie speed sensors/broken wires, topping off the reservoir, new pressure sensor, etc.

About a year ago, my tilt lock motor was severely rooted similar to yours, just one continuous beep. It turned out that the tilt lock motor was screwed, or more correctly, a rod/piston inside the motor (visible through the black plastic cover on the front RHS) had rusted and seized up.

So I swapped out the entire tilt lock motor with a second hand one out of an MP3 500 and it has worked flawlessly ever since.

Some recent shenanigans with tilt lock motors Replaced tilt lock motor

Thanks everyone for the help. I went through some of the troubleshooting tips after opening up the front casing and think I have the culprit. The pressure sensor has some brake fluid around it, so I assume it is the problem and I have heard this is a common issue.

I don't want to make a bigger issue that necessary, so I am fearful of breaking the blue clip in trying to remove. Anyone have any tips on removing safely?

It has been a while since I had a go at mine but I think I used a small screwdriver to depress the the locking tab on the plug. You should measure a short cct across the switch when the tilt lock is engaged.

Thanks, Oldgoat. Got the clip removed (it was super stuck due to dried brake fluid). I found fluid in the plug so I assume that the sensor is busted. Right?

I unplugged and restarted. Lock now engages but the beeping persists. By my research, I thought this would solve the problem. Anything else I should look at?

I am pretty sure the pressure switch tells the roll lock ecu to turn on the dash lamp showing the front suspension is locked an d also shuts off the the alarm cct. If you operate the roll lock and short out the plug it should shut off the horn.
Can understand why you don''t want to replace the hydraulic switch with piaggio's overpriced part dont see why you couldn't replace the switch with a standard brake light hydraulic switch assuming it doesn't have some strange thread

I wanted to make sure that the switch is busted prior to ordering a new one (75+ shipping with no returns). I'd be happy to pay if this solves all issues, but just seeing if I'm missing anything. I assume that I won't know if I'm successful until switching out the part.

That switch is certainly buggered so go ahead and buy a new switch. You will have to bleed the hydraulic lock again. I have found the easiest way is to bleed it from the bottom and I use a 50 ml syringe and a bit of tube.

There are a few US dealers for parts that should make the purchase of replacement switches and parts less painful and expensive.

Scooter West ships from San Diego, CA area and often has parts in stock from their service department. https://www.scooterwest.com/catalogsearch/result/?q=tilt+switch

Scooter Parts Co ships from US East Coast and often has parts in local warehouse
https://scooterpartsco.com/index.php?main_page=search_result&search_in_description=1&keyword=tilt+switch&x=0&y=0

AF1 racing lists the parts but doesn't have them in stock and you must already know the part number. They ship from Texas but have long lead times.
https://www.af1racing.com/

I've been reading about the "push bleed" concept. To make sure I understand correctly, this would mean I would want to fill the syringe with fluid and push new fluid until it fills the reservoir?

Thanks for the US links! I would much rather support US shops.