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Lou P. master tech
Lou P. master tech, Mercedes Technician
Category: Mercedes
Satisfied Customers: 3726
Experience:  15 years master certified 100% fix rate and have access to factory radio codes, wiring, and instructions.
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C300: , i have a 2008 C300, i just replaced the remote

Customer Question

hello, i have a 2008 C300, i just replaced the remote batteries and they are in perfect conditions but the remote isnt working... Any help pls?
Submitted: 1 year ago.
Category: Mercedes
Expert:  Lou P. master tech replied 1 year ago.
Hello my name is ***** ***** i will do my best to help you , i strive for EXCELLENT service and nothing less. Near the panic button is a small light that will light if you hold any one of the buttons down for about 4 seconds. Try this and tell me if the small red light comes on. It is just to the left of the panic button. Very small light.
Customer: replied 1 year ago.
i just tried... it dint come on!
Expert:  Lou P. master tech replied 1 year ago.
Ok soupy only have one key? Also look at your drivers door handle. Is their a little black square near the end of it ?
Customer: replied 1 year ago.
Yes Lou, just one key, and YES there a black square near the end..
Expert:  Lou P. master tech replied 1 year ago.
Ok. Point the key directly at that square within a few inches and hold the unlock button down and tell me if the doors unlock and the windows roll down. Hold for like 5 seconds
Customer: replied 1 year ago.
i just did... nothing happens!
Expert:  Lou P. master tech replied 1 year ago.
Ok , does the key start the car ?
Expert:  Lou P. master tech replied 1 year ago.
Also if you have a camera phone. Turn the camera on and point the key at the camera and press the button. You can actually see the infrared from the key if the key is working
Expert:  Lou P. master tech replied 1 year ago.
Autozone also has a tester you can check the key signal with. I think your key is bad. The keys are common to fail after years of use. If you know anyone good with electronics and circuit repair they may be able to take the key apart and check the circuit board. Sometimes the battery hold down breaks off the circuit board and can be soldered back in. But other than that a new key will have to be purchased at a dealer. And you must provide proof of ownership to order a new key. The keys are around 250$ for a new one and come programmed to your car so you will be able to insert the key and wait for the dash to finish saying "learning new key" or something similar I can't remember the exact term. Hope this helps. Let me know if you need anymore information I am here to help. Please take a second and click the box and rate my service GOOD OR EXCELLENT SERVICE if you feel I have been helpful and please request me in the future. If you feel I have not been helpful please DO NOT RATE BAD OR POOR AND WASTE YOUR MONEY , I will opt out to see if another expert can provide more or better assistance so you're not wasting your money!!. Thanks for choosing just answer. Lou. also , if you feel i deserve one , BONUSES are GREATLY APPRECIATED ! 😉
Again if you need further help please let me know. Lou
Expert:  Lou P. master tech replied 1 year ago.
I have taken my time to answer your question the best i could and i will continue to help if you need follow up information , all i ask is that you PLEASE take a second to rate my service so i may recieve my credit for assisting you. Thank you.
Customer: replied 1 year ago.
No luck with getting it to work yet!
Expert:  Lou P. master tech replied 1 year ago.
well what are you trying to do now exactly?
Customer: replied 1 year ago.
get the remote to work again... its starting the car effortlessly
Expert:  Lou P. master tech replied 1 year ago.
so the car starts with the remote but will not work the locks? i thought the key did not start the car?
Expert:  Lou P. master tech replied 1 year ago.
if you need more info i am willing to help, if you want to chat over the phone just accept my offer and then we can be able to come to a conclusion, but if you do not provide me with the info i am asking it will be hard for me to give you a very accurate answer. i have been doing mercedes for 15 years. i can definitely get you in the right direction. Lou
Customer: replied 1 year ago.
i tried the camera phone trick, nothing like an infrared light showing.... wht do u suggest ido next?
Expert:  Lou P. master tech replied 1 year ago.
Ok perfect !!! If you do not see any thing in the camera then the Key has failed. You need to buy a new key. That means that the key is not sending the signal to the car. So you must go buy a new key from the dealer. There is nothing you can do to fix the key.
Expert:  Lou P. master tech replied 1 year ago.
I have taken my time to answer your question the best i could and i will continue to help if you need follow up information , all i ask is that you PLEASE take a second to rate my service so i may recieve my credit for assisting you. Thank you.