Chrysler Repair/'07 pt cruiser wagon: brake/tail lights don't light
QUESTION: The #3 fuse is okay. I'm diagnosing as I write this. The turn signals work and the key fob makes the turn signals blink, so... those lights aren't back up lights like the lights in the fender. Also the light in the window works. So it's only the red lights in the quarter panels fish eyes.
Purchased 2 weeks ago and only am able to assume dealer made sure everything was working. He hasn't returned my call (typical?). Only has 35K miles?. Good for me...but.
Does anything obvious come to mind? Could it be as simple as the switch on the brake pedal? Or two lamps, to me doubtful? I was warned by a friend to be a little careful poking into the wiring because the air bags are in the circuit. I'm thinking I might just as well take the car to my local repair because the dealer I bought the car from is a Toyota dealer and is an hour away and maybe a pain to deal with now that I have the car.
I'll call if that helps us.
Thanks for your time. I appreciate it.
ANSWER: Hi Tom,
The electronics for the brake lights are as follows:
fuse 3 is correct so verify that it does show 12v on both pins, and that there is 12v from it reaching pin 1/red wire of the brake pedal switch so as to supply the switch at all times.
the 12v output of the brake pedal switch is at pin 2/orange wire so check there for 12v when you step on the brake.
That orange wire goes to pin 13 of the 16-pin plug at the power box in the engine compartment.
That box has about 13 plugs but only one with 16 pins.
The 12v bulb output of that box is at pin 7 of the same plug which has a dark green/white wire and that wire goes through a couple of plug/sockets to the rear brake lights that are not working.
Each bulb has a separate ground, so the only possibility is that both bulbs are burned out if you indeed get 12v on the dark green/white and it is reaching the bulb sockets. Let me know if not and I can tell you about plug/sockets of the pathway back to the rear.
It is a bit more complicated than typical, but you should be able to trace this down for why the bulbs are not lighting. I don't think the air bags are close to this circuit so I doubt you would set those off. Let me know if you have questions.
Thanks for the rating/nomination,
---------- FOLLOW-UP ----------
QUESTION: I forgot to note that the tail lights don't come on either with the headlights being turned on. Sorry.
Hope that doesn't change your diagnoses.
I will take a look to try and keep the car here. I've been out of work too long and need to save the green.
Again can't thank you enough.
Yes, if the tail lights are out too then that changes the diagnosis and suggests one of the plugs from the instrument cluster area that goes back to those rear lights is unplugged, especially also if the license lights are also out. So forget the brake switch as the cause.
The output voltage for the park and the brake lights at the rear is from the front power box in the engine compartment whose internal wiring is "a black box". Is the license plate light also out? How about the rear turn signals?
One possibility is that the wires from the engine compartment power box to the rear are compromised, possibly at a plug/socket connector that is disconnected. Go to the 16-pin plug at the power box in the engine compartment I mentioned earlier and check whether pin 8 white/violet and pin 13 orange show 12v when you have the lights 'on' and have the brake pedal pressed, respectively. Then we'll know what to do next.
Feel free to do another rating and nomination if you would be so kind.