2010 Prius Intermittent Front Wiper Problem, works when pushed

Sounds like a weak motor

 

It's the switch contacts in the wiper transmission. Almost every car on the road does this the same way- the wiper power is routed through the stalk switch, and wired in parallel to a secondary switch inside the wiper transmission. That second switch is open when the wipers are at the full-down park position, and it closes when the wipers are in any other position. This way you get automatic wiper parking.

The switch inside your wiper transmission has worn or broken. I haven't tried to repair a toyota wiper assembly, but generally speaking they aren't worth it. Much easier just to replace the assembly with a used one from a junkyard.

It's an integrated assembly that includes the motor, usually looks like this:


(general reference only; not a toyota part)

In this example the transmission is the black plastic box in the middle, but the junkyard would almost certainly deal with it as a complete assembly as pictured.

 

They'll work when they're free up in the air because there is enough inertia in the assembly to re-close the internal parking switch. The delicate "make or break" balance is shifted towards "make." When the wipers are on the glass, there's too much drag. Sometimes you'll see a difference depending on whether the glass is wet or dry- the water lubricates the blades.

Still needs the same fix.

 

I had the exact same problem on my Prius. Wipers would intermittently stall in speeds 1 and 2, but will always work at speed 3. Opened up the wiper motor, and found out that the carbon brushes for the two slower speeds were worn down, and all the crud and debris inside was preventing a good connection. All it took was a through cleaning of the carbon deposits to restore function. Had me really panicking at first. If you ordered a used motor, it might also be dirty inside. You may still be able to recondition your old motor and reuse or sell it.

 

I have the same issue...took it to a mechanic and told him to clean the debris but he told me after inspecting it that there was no dirt/crud there and would replace the motor for me (over $100). He seems like an honest mechanic but I'd like to inspect it myself (if it is easy to do). Can you provide some detail as to how you went about doing this...hopefully I won't have to get the mechanic to replace it.

Thanks.

 

Am having basically the same problem. If I have to remove the wiper assembly then open the motor then brush and clean something I’m going to to take it to the shop and have them replace.

Would it make sense to have them replace the spark plugs, as well, since I believe you have to remove the wiper assembly to replace the spark plugs? Those are due in 15k miles which is about 1 year of driving. We currently have 225k miles and we last replaced them at 120k, so they’re due at 240k.

We hope to get about 2 more years out of the car which is about 30k miles for us.