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I have a 2006 Land Rover LR3 that is throwing error code p0504. All of the lights on the dash are illuminated. I have replaced the Brake Light Switch as well as all of the tail light bulbs. I also replaced the battery. The error is STILL happening. Any suggestions on how to fix this?
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The possible causes of the P0504 code are: - Faulty stop lamp switch- Blown stop lamp bulb- Brake switch harness open or shorted- Brake switch circuit poor electrical connectionRead more: http://engine-codes.com/p0504.html#ixzz2hHO5HQ4i
you should look for loose wires on the brake pedal sensor. Also, have someone depress the brake pedal and verify that all the brake lights illuminate.
These are things that have all been checked, so unfortunately this answer is not sufficient. The car will just be taken to Land Rover for evaluation.
Unfortunately this vehicle is a bit more complex than that. The high stop lamp and all the other lamps function properly which makes this a bit more difficult than the typical brake light switch problem with the LR3. I have literally exhausted every possibility and thought I would give Just Answer a last minute long shot on a resolution. Please do not take my dissatisfaction with your answer to heart as I was hoping some Land Rover mechanic had a hail mary to solve my problem. Off to the dealership unfortunately!
Rating is simply based on the expert not having any new information for me to go on. This car is complex and this is by no means a reflection on this expert.
Hello, I'm Chris. Thanks for visiting Just Answer.
Different tech here
With the key on the Green/Orange wire at stop lamp switch needs battery voltage. When the pedal is pressed, the Green/Purple wire will get voltage. At the Red wire on the stop lamp switch, there should be battery voltage only when the key is on. The Purple/Green wire will also have voltage, then lose it once the pedal is pressed.
The voltage must match battery voltage, the common issue is voltage drop from poor connections or wire issues. Also sun roof drain leaks effecting connectors in this area are common.
If all tests have so far passed then test the voltages at the ABS, Purple/Green and the Green/Purple wires need to be the same as battery voltage.
Just as a followup, the car was taken to the Land Rover dealer to get this issue fixed. It turned out to be a bad ABS/Speed sensor on the right rear wheel.