2005 Prius won't start after changing headlight

welcome! how many miles on her?

it sounds like they are resetting the system, but that's not solving the problem. although, the bump sounds like a loose connection, you should see if any trouble codes have been logged.

 

i would like to know what they are fiddling with in the hatch, and how they know to do that.

if the problem is in the front, how is disconnecting and reconnecting something in the back temporarily fixing it?

 

nope, just a priuschatter.

 

I suggest you get Mini VCI so you can retrieve the DTC logged by the skid control ECU. If the ABS light is on then at least one DTC was logged.

 

The Mini VCI is a cable which, when combined with a Windows XP or Windows 7, 32 bit OS laptop and the software which comes with the Mini VCI, allows you to utilize the same diagnostic power as a Toyota dealer tech using Toyota Techstream. The Snap-On scanner apparently could not retrieve the DTC logged by the skid control ECU, but if you had the ABS warning light on, a DTC was present.

 

They are likely just unhooking then connectors from 12v battery in back which will clear codes that are in memory.

 

Even though 12v is one year old it could be low in charge or bad if it was discharged a couple times. What kind of 12v is it? See prior threads about how to check 12v

PS- Several Youtube videos on Gen2 light bulb replacement I assume you are talking the regular bulbs ...2 methods you either have to be a contorsion artist (my approach) or take a few pieces off per Lucious garage video. But we do not have too many reports of bulb replacements gone bad. I do not know what shop you are going, but some Prius experience helps.

 

Check to see if you have anything loose in the fuse box behind the driver side headlight. My guess is that they moved it over get better access to the headlight. They then put it back without checking the connections/fuses/relays for proper contact.

 

I don't believe this is related to the headlight replacement, just coincidence but you need the codes read while the lights are on. It is behaving like a high voltage ground fault P0AA6 code. Like Patrick said you will need the mini VCI to check. Once the P0AA6 code is set the car will not restart until it has been fixed/cleared which is why disconnecting the battery clears it and it restarts. The mini VCI will possibly confirm my suspicion and identify the location of the ground fault.

 

We see it all the time. Its not a coincidence. Those incompetent people worked on the car without disconnecting 12v first. Doors open, maybe even in ACC mode so they can check headlight wiring and operation, etc. Battery got discharged. Its a small 20-24 AH battery.
Now they have to charge you for new battery and other BS that is happening to the car. They probably did not re-connect the battery properly (including the cense wire) after charging/replacing it. That's why you have codes after bumps on the road.


At least they did not jump it with reversed polarity and did not destroy a $3000 inverter

-Alex

 

While it is a smallish battery, it's not that small.

The OEM for non-SKS is 36 aH;
The OEM for SKS is 45 aH.

 

You can fully charge the battery back up. As long as this is done soon after the battery was discharged, it will not do any long term damage. The longer you wait to fully charge up the battery the greater the chances of damage occurring.

 

I thought OP wrote that the 12v was replaced after the first episode. In any case I do not see why a 12v on its last legs would only be affected by a bump in the road, or why a reset would let the car go again.

A loose connection or a ground fault sounds right to me. I would follow TampaPrius' advice and also re-seat all the connections in and around the fuse box.