Electrical problem or just headlights?

It's not likely that this is caused by a single bad bulb. You have some sort of an electrical problem which should be checked.

Tom

 

Barcelona Red Lass -

Attack one problem at a time. Try to rule out the most common and easiest to repair failures first.

The back running lights are the easiest to diagnose and repair. Your owner's manual gives you instructions on how to locate and replace the rear bulbs.

First try simply removing and reinstalling the existing rear running light bulbs. This solved the problem on one of my rear lights. I'm not sure if the bulb was not properly seated or if the contacts were dirty, but removing and reinstalling the bulb fix my problem.

If removing and reinstalling the existing bulbs does not correct the problem then buy two new bulbs from your local automotive supply store. The bulb number is marked on the bulb and is also listed in your owner's manual.

The headlights are somewhat more difficult.

First, you'll need to determine if your car is equipped with Halogen or HID headlights (if you don't already know). If you have your original window sticker it'll list which headlights are installed on your car.

Are the headlights dim while your are driving the car? While the car is idling, With the engine off?

 

Once again, no. The electrical problem that causes headlight trouble for some Prius is from the HID headlight system. Those problems are confined to the HID capsules and controllers (ballasts). Unless there is an overall 12V power problem with your Prius, it is unlikely that the headlight issue is related to the tail lights.

You need to determine if you have HID headlamps. When you turn them on, do they flash brighter just for a second? If so, they are HIDs. Another way to tell is to look at one while someone switches between high beam and low beam. With HIDs, a small shutter moves to block the upper light output. With halogens another light element is powered to produce the high beam.

With respect, your confusion and lack of understanding of the fundamental differences of HID verses halogen suggests that you might not be the correct person for a DIY repair job. Do you know a technical person who can help?

Tom

 

The VERY first thing you should check before you start dissasembling your baby, check the FUSE'S!!!

Look in the manual, it points the location, and their function. Find the one that supplys voltage to the rear lights. Just replace with a KNOWN GOOD fuse. Still have the problem, then move on. If bulbs test good, then you have bigger problems to worry about, it's dealer time!!!

 

Barcelona Red Lass -

The attached Toyota "How to Replace a Bulb" publication may be helpful.