Touch switch won't open liftback

Sorry to resurrect an old post but I have a 2009 Prius & the rear hatch suddenly can’t be opened from the outside (I currently have a cable inside so can open it from inside!).

Pressing the hatch button beeps & locks / unlocks the doors but not the hatch. The voltage at the hatch latch connector is less than 12v but not sure what it should be? I have given the latch a good spray of wd40 & ensured the battery is fully charged but no change. There’s a replacement latch (as pictured) at the wreckers but not sure if I should try anything else first? Thanks in advance..

 

It should be roughly the same voltage as you measure at the battery so if your battery is also 'less than 12 V' then that confirms power to the latch mechanism.

I had a similar experience (in a non-SKS Prius) and after I confirmed there was no problem with the connector (i. e. it had power to the connector) and that it was firmly seated, that confirmed to me the latch mechanism had failed. I bought the latch mechanism from a wrecker and replaced it. That was back in 2016 and that repair is still solid.

I felt comfortable with a wrecker's part as I had not heard of these failing very often.

Also of note, the power is supplied to the latch for only about 500 ms (per press) so you should see that at the power wire when you press the hood latch switch.