Flashing green and red sensor lights

[konas]

I drive a 1996 mercedes C200. Each time I open the door with the remote, the green and red light on the inner rearview mirror and the door handle start flashing, an indication that the car will not start no matter how much I try. I changed the mirror, but this did not solve the problem. Please advise.

 

[mikestrivens]

I think this might mean the keyfob batteries are low. But I will need to check manual to confirm.

 

[bigasotonuk]

Hi,
Welcome to the forum,
As Mike says it is usually a sign of the key fob batteries being flat, if the car won,t start they are flat, and the immobiliser is staying on. The red & green lights need to work on both the door handle and the mirror or erratic operation of the immobiliser will occur.

 

[AMG99R]

Flashing red and green lights

Hi, I'm new to the forum and have read a few threads and am even more confused!

I have a C36 1996 AMG. A few weeks ago, the rear view mirror started flashing red and green when I pressed the remote. I changed the batteries and it worked fine for a week or so then it started flashing again so I bought new batteries and the car worked fine again for a week.

Last Friday when I pressed the remote there were no lights on the rear view mirror so I entered the car through the passenger door key and as a result set off the immobiliser. So I resynchronised my remote by putting it in the ignition and turning to the 2 position then taking the remote and pointing it at the rear view mirror and pressing the remote 5 times. The car worked normally again until today when the red and green lights started flashing again!!

Help what is wrong with it?!

 

[Alex Crow]

are they on and off together, or alternately?

 

[AMG99R]

each time it has happened in the past 3 weeks, they have been on and off together which the manual says means that the batteries need replacing but I have replaced them 2 times now and each set has only lasted a week!

 

[A180 Dream]

each time it has happened in the past 3 weeks, they have been on and off together which the manual says means that the batteries need replacing but I have replaced them 2 times now and each set has only lasted a week!

Are you making sure that you wipe the battery terminals before putting them in the remote..................They may look clean, but often have a preserving thin film on them which can give a premature "flat battery" indication.

Also check that the contacts in the remote are clean

 

[AMG99R]

No I didn't know I had to wipe the terminals or the contacts as I have always replaced the batteries in the past 10 years by just putting in new ones and they have always worked until now. I will wipe them when I get home tonight and see if that works.

Thanks.

 

[Dec]

I wonder if the type of batteries you are using has anything to do with the problem. I think Lithium are the best for this purpose.

Dec

 

[AMG99R]

Thanks for sending in the photos. I have tried all that and am getting the red flash as well and the blue/white light! The remote is still sending a signal to the car as when I press it the car unlocks and I can start the car but it is still flashing red and green simultaneously even with new batteries that I put in 2 nights ago! All the batteries that I have bought are Energiser Lithium batteries! Any ideas?

 

[Dec]

If you are putting in new batteries and the are solving the problem immediately and then after a few days/weeks the problem returns then as already suggested elsewhere by Malcolm on another thread, there must be a drain somewhere in the key or else all the batteries that you are buying are on there last legs.

You can still lock/unlock and start the car and the remote does past the above test so the only other explanation is perhaps there is an intermittent fault in the mirror giving you a false alert and there is in fact nothing wrong with the batteries at all, as you say the are passing the test and the are locking and unlocking the car.

Dec