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MB Paul
MB Paul, Mercedes Technician
Category: Mercedes
Satisfied Customers: 3567
Experience:  Qualified Mercedes Benz Diagnostic Technician - 20+ years experience - Workshop Foreman for Mercedes
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I cant start my car its a Mercedes c280 1996

Customer Question

I cant start my car its a Mercedes c280 1996 these green and red light start flashing when I try to start it
Submitted: 1 year ago.
Category: Mercedes
Expert:  Billy replied 1 year ago.
Hello and Welcome! I'm Billy and i will assist you with your inquiry. Feel free to ask if any further info is needed.
My apologies for the delay, thank you for your patience.
The green and red lights flashing indicate an immobilizer problem. This is whay the engine is not starting.
Is your remote key fob operating?
and did this problem start suddenly, or after some repairs, etc..?
Customer: replied 1 year ago.
no repairs it just suddenly started
Expert:  Billy replied 1 year ago.
Is the remote locking/unlocking working using the key fob?
Customer: replied 1 year ago.
the remote on the key chain has always been broken we have always used the key on the remote
Expert:  Billy replied 1 year ago.
i know the key would start the engine even if the remote is not functioning. Those are separate functions, but if the key fob was working, we could've tried a reset procedure.
There is a small rectangular transponder chip in the key fob, it is black, the size of a small pill, would you be able to open the fob to check if it's there? as this is the transponder for the immobilizer system.
and while in the car, with doors closed, try locking, and then unlocking using the switch inside, and then try to start...
Customer: replied 1 year ago.
I see the rectangular put it has nothing that you are describing
Expert:  Billy replied 1 year ago.
Sir, you are deviating from an efficient diagnostics path.
The small rectangular black, pill like chip, is it inside the fob? did you open the fob to see it?
and could you try the following:
with doors closed, try locking, and then unlocking using the switch inside, and then try to start...
Customer: replied 1 year ago.
I will try the following but as I said before there is no small black chip in the control
Expert:  Billy replied 1 year ago.
try the unlocking procedure, and if that doesn't work, kindly check the other key fob:
you need to open the fob, and under the circuit, there in the plastic, near the top of the fob, check for a small plastic part, with some writing on it (very small writing)
Customer: replied 1 year ago.
what is the fob? I went into the car locked all the doors and tried to start it the red and green light would turn on and the engine wouldn't start
Expert:  Billy replied 1 year ago.
The key fob is the key remote control.
you need to lock, then unlock the doors (using the switch that is inside the car) and then try to start. did you try that?
This way we're eliminating possible causes...
Customer: replied 1 year ago.
so we know that the control is broken and that I locked myself in the car and then got out. I did try to start the car and that's when the lights started going on and off
Customer: replied 1 year ago.
did it again twice and it still doesn't work. if the car has had no problem w the control not working all these years why is this happening?
Expert:  Billy replied 1 year ago.
It is a simple procedure:
- get in the car, close the door
- using the switch for central locking that is inside the car, lock and then unlock the doors
- try to start
Does it start after trying this specific procedure?
and does the central locking work, using the switch inside the car?
PS: the remote locking/unlocking is a different system, and the car should still start. but kindly try the above procedure to the letter, and get back to me with the answers to both questions.
Customer: replied 1 year ago.
I got in the cae the central lock does work to close and unluck the car. then I tried to turn it on and it would not start and the green and red lights started going off again
Expert:  Billy replied 1 year ago.
Ok, so now we now that the PSE (pneumatic) unit is not causing this (this is the most common reason for failure).
Having tried this, a spare key, would you be able to check for any blown fuses? (this is the last resort, as the next step would including diagnosing the immobilizer integrated within the ignition switch, and reprogramming the keys, or replacing)
Customer: replied 1 year ago.
Then my husband has done everything you just said sorry you could not help us is this refundable?
Expert:  Billy replied 1 year ago.
I have explained what is wrong with the vehicle. How to check. What to check. And we came to the conclusion that the system needs resetting using a star scan tool. And if that doesn't work, the ignition switch needs replacing, and then reprogramming.
I sure hoped that there was something more i could've done from the other side of this computer. But this is my work, i tell you what to check, until we find the culprit, but i cannot physically fix it, you'll have to do it.
But since you feel this way, i will report this to customer service so they arrange you a refund.

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