Skip the auto shop - Our mechanics make house calls

Q: Brake/ tail lights

asked by on

My light failure sensor bad (burnt spot on circuit board), I got another one and after a few seconds it happened again so I simply bypassed the sensor (removed it) and for some reason both filaments light at same time in all 4 of the 1157 (brake/tail) bulbs ....they do get a little brighter when I hit the brake but it's not working like it should. Also when my running lights are OFF my dash lights dimm when i apply the brake but when my running are ON the dash lights are fine...please help if you can thank u

My car has 101000 miles.
My car has an automatic transmission.

You have a short circuit (possibly to ground) in the wiring for the board OR a fault in another component on the same circuit that is allowing too much current to flow through your sensor board causing it to fail. Best thing to do is do the electrical diagnosis, find and fix the short, and replace the board. YourMechanic can assist you with the electrical wiring diagnosis and procure a replacement board for you.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Car rumbles when accelerating for the first time after not using the car for 12 or more hours.

Hi there: What you're describing could be several issues ranging from clogged fuel injectors or dirty fuel filter to electronics related with a problem with the ignition coil or a sensor; even a vacuum leak. If you turn on the...

Q: My car is still dying out after replacing the alternator and battery

Remove the negative battery cable from the battery. Get a digital meter and check the voltage from the battery terminal and the battery cable without having the cable touching the terminal. If there is something on in the vehicle with...

Q: Part identification

From what you've described, the only thing I can think of is the heater control valve. Sometimes people will put in a flush fitting inline of the hose. If what you're talking about it the heater control valve it will...

Related articles

How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...
P2428 OBD-II Trouble Code: Exhaust Gas Temperature Too High Bank 1
P2428 code definition A P2428 trouble code signifies that the PCM has detected a problem in the exhaust gas temperature sensor circuit in bank 1, which subsequently contains the number one...
P2103 OBD-II Trouble Code: Throttle Actuator Control Motor Circuit High
P2103 means there is a fault with the throttle actuator control motor circuit, likely due to a defective electrical component or part.