Tail Lights & Turn Signals not working.

Sounds like it's a switched lights issue everything that really needs to work does because I guess they're on separate circuits the brakes and hazards but the lights that are being switched by the light switch which are the running lights and what's happening with the headlights when the light switch is fully on do you have headlights??? Have you checked all the fuses that's why I'm asking if the headlights work??. So when you're in the park light mode are the Amber 194 parking lights in the front of the car on but the tail lights in the rear the bottom ones the 194 bulbs are not lit? Or are the Amber's in the front not lit and the reds and the lower portion of the tail light not lit at the same time this is kind of important has anything been done to the hatch of the car any ground points been loosened or messed with grounding is kind of done like that.

 

Pretty sure that you can access the bulbs/wiring at the rear by:

1. Open the hatch.
2. Pull off the plastic piece that surrounds the loop for the latch just above the bumper
3. Remove the two bolts on one side piece (one has a cargo loop, the front one is deeply recessed)
4. Remove that side piece (starting at the lower part of the hatch pull up, feel underneath with your fingers for the solid part and lift there - if you just yank on the cardboard stuff things will break.)
5. Once the 3 (I think) connectors at the hatch are out just pull off the side piece.

If any of this is unclear go find a video on replacing the HV battery, they will show how to do this.

Then you should be able to access the back of the taillight assembly. If it is like most cars the bulbs will come out by twisting a plastic plug one way or the other by up to a quarter turn, and then pulling it out. At that point you can check for the presence of voltage. You never know, the bulbs might have just gone out over time and you never noticed.) If there is no voltage when there should be find the wiring diagram (somebody probably posted it on this site at some point) and work from there.

Was any work ever done on your car related to or near the relevant parts of the wiring harness? It may be that they forgot to plug something back in. It happens.

 

You don't need to disassemble the tail lights yet because the lights you're trying to get working or just the tail lights they're just the 194 bulbs plugged in to the gray twist in assembly that goes into the tail light You should be able to lift the plastic piece in the back twist out that bulb and leave them dangling now put the park lights on and my question still stands when the park lights are on are the little orange park lights high up on the headlights lit up in the front??? If yes then we're getting power to the running light park light circuit now with your voltmeter or test light take the bulb out of the socket that you removed from the tail light and it's just dangling and probe that because the switch is still on and see if your test light lights up for you get 12 volts at that receptacle If so try another light bulb I use LEDs here 194 Sylvania Z something I use red ones in the rear because they're in a red clear shell. If the orange lights in the front don't light up when you turn on the park lights then it seems like your park light circuit is not firing up at all but you have brake lights you have flashers You probably have turn signals You just don't have the little red 194s on the bottom and the tail lights and the same high up in the headlights? I doubt there's anything running directly to ground and if so it just didn't fall off and start happening you would have somebody would have had the car apart that sort of thing I mean a mouse chewing a wire yeah sure it's possible but that wire being live and now just laying against the frame of the car that gets to be a stretch The wires aren't usually long enough to go that far.

 

The main points here are:

Troubleshooting steps to fix tail lights issue

• Check if the little orange park lights high up on the headlights are lit when the park lights are on
  
• If the orange lights in the front don't light up when you turn on the park lights, then it seems like your park light circuit is not working
• If it does seem like your park light circuit is working:

1. With your voltmeter or test light, take the bulb out of the socket that you removed from the tail light and let it dangle.
2. Probe the bulb with the voltmeter or test light while the switch is still on, and see if your test light lights up and you get 12 volts at that receptacle.
3. If you get a positive reading, try another light bulb.

​

• There could be a possibility of a mouse chewing a wire or a loose connection, but it's not likely.

 

The Amber lights in the rear would be your turn signals You said those are working those are also your flashers when you put the hazard button triangle on the dash generally if the hazards are flashing in the rear they should be flashing in the front that'll be your turn signals that'll be flashing in amber for your hazards that means by right your turn signal should work If not it's probably the switch and they are marked as working You say the front and rear ambers are not working now you've confused me again The Amber's in the rear will only be your turn signals You say they are working The little Amber marker lights that come on with your tail lights the small bottom red ones the Amber's I'm talking about in the front are the little 194 way up in the corner that come on on the first step of your headlight switch not the turn signals in the front which are Amber but we're not discussing those now we're discussing the running lights they'll be amber in the front little tiny in the very corner and red in the rear very bottom of the tail light That's what you should have going on

 

So, I would turn the parking (tail) lights on, then use a 12V test light or a multimeter to see if you have 12V power present at the #16 TAIL fuse (10A) in the underdash fuseblock.

What should happen is that the light switch should signal the body control ecu to activate the tail light relay, which supplies power to fuse 16 and from there to all the parking & tail lights.

We want to see if the problem is on the output (relay, fuse, and light) side, or the input (light switch and body ecu) side.

Having a capable scantool to monitor body ecu data would be useful for something like this.

 

There are really cheap ones available locally too. Try Harbor Freight, their bottom of the line model is under $10, and it will suffice for this task. (However, the leads will break eventually, because they are cheap crap.)

Harbor freight Cen-tech 90899 small teardown - Page 1

It isn't a terrible idea to keep a multimeter in the car, but Murphy's law means that whenever you need it on the side of the road its battery will be dead. For that reason there is something to be said for the old fashioned analog meters like this one:

Commercial Electric Analogue Multimeter M1015B - The Home Depot

They have a battery too, but it is only used for resistance measurements, and most of the things one would check when it would need to be used away from home are voltage measurements which will still work.

A good multimeter with decent leads would be at least $50. And do NOT believe the voltage ratings on made in China multimeters, most of them are pure fantasy. It may say 600V on the case but you would be risking your life to use one there. Lots of info available on these devices:

Index of reviewed multimeters table

or

Multimeter spreadsheet (80 manufacturers and over 400 meters listed) - Page 1

 

I keep a midline fluke In glove boxes and storage compartments of various vehicles that I drive or use I actually have like a bug out bag that has to be with me in any vehicle that I'm driving because I have so many vehicles like seven on the road so anytime I jump in one of the Prius I have this bag that goes with me and in that bag is my test meter my go-to things that need to be with me generally anytime I'm out on the road in the woods whatever it's just equipment that I need to do things wherever I am doesn't matter rather than to have to run back to the shop or have my friend look through all his tools to find something I just opened my bag and there it's laying and everything goes back in that bag while I'm out doing whatever we're doing and then that bag goes with me every morning no matter what vehicle I get in that bag has to be with me I don't pull out of the driveway without that bag ever if I have to run out at 4:00 in the morning with guns of blazing that bag is right by the door and goes with me. There's no discussion about it my other half knows to grab it if we're in a big hurry.

 

So the first click on the light stock nets you no outside lights but the dash lights up? The first step on your lights is your park lights that should give you dash lights indoor dim the dash lights when they come on if the wheel is turned above your knee on the left side.? And you say the front Amber parking lights are on so I guess the lower rear red running lights are not on also Is this correct? Again.

 

Turn the light switch on to the first detent (parking light position). Do any lights on the exterior illuminate?

Turn the headlights on. Do any exterior lights besides the headlights illuminate?

If "no", then you need to check for power at fuse 16 when the light switch is turned on.

If "yes" (one or more parking/tail/corner marker lights come on), then the relay and fuse 16 have power and the problem is somewhere in the wiring.

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