Cannot Central lock and set the alarm using the remote-control key?

2002 MERCEDES BENZ 500SL

32,000 MILES • 5.0L • V8 • 2WD • AUTOMATIC

IVAN MCDOUGALL

MEMBER
3 POSTS

I can't Central Lock and set the Alarm using the remote control key. I have charged the batteries (Engine and Consumer) and replaced the remote key batteries also, but nothing happens when I press the remote any of the 3 buttons. the remote light (red) does come on, on the remote.

Mar 9, 2025 at 7:41 PM

STRAILER

✓Experienced Mechanic
55,051 POSTS

The remote is bad if the red light does not come on which is common. Here is a replacement which you can reprogram for $29.00 from amazon:

https://amzn.to/3FfrYVI

The instructions are included with the new fobs. Please let us know what happens.

Mar 10, 2025 at 6:00 AM

IVAN MCDOUGALL

MEMBER
3 POSTS

Hi Ken L, I did say the red light comes on as a process of elimination but I'm delighted to know I can get a replacement from you.

Mar 10, 2025 at 3:10 PM

IVAN MCDOUGALL

MEMBER
3 POSTS

Sorry, I should have added to the last post that I am still without a solution.

Mar 10, 2025 at 3:22 PM

STRAILER

✓Experienced Mechanic
55,051 POSTS

Opps, sorry read it too fast. I would check the fuses #16, # 5 and #6 in the trunk for the security system and if they are okay let's do a CAN scan, this video will help:

https://youtu.be/u-4syLc-ifQ

Here are the wiring diagrams for the system. Here are the fuse locations. Check out the images (below). Please let us know what happens.

Images (Click to enlarge)

Professional Diagram for 2CarPros Members
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Mar 11, 2025 at 5:38 AM

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