Hi, Folks,

Took my '99 E430 to the shop when the driver side controls stopped working (seat, mirror, windows). My guy did a complete electrical scan and found no issues or outstanding errors messages stored. He removed the driver side control module, cleaned the contacts & re-installed it, problem solved, everything worked for two days.
Yesterday (a rare rainy day in SoCal) it all stopped working again in addition to the smart key. Replaced the key batteries, no response. Using the blade key to get in & out, but at least it starts.
Also, we've been getting the 'bulb defective' display constantly, whenever you turn the car off, turn the lights on/off, or hit the brake. Every bulb & contact in the vehicle has been checked and replaced if necessary.
Seems like the electrical glitches are are spreading.
Has anyone encountered this? And is there a way to do a 'soft reset' of the system?
Car has 162K miles and has always received all scheduled maintenance. Physically & mechanically she's mint.

Many thanks,

Tony

 

Im about to bring it to my mechanic today to check. It started yesterday. Now, it happen again.

 

Do you have after market lights? I have HID kit on mine. Lamp defective comes on only when I turn off the headlight while the engine is running. But when I turn off engine it wont do it. Wonder if it has something to do with it.

 

Stock lights, but the same thing happens. Another member suggests disconnecting the battery for 5-10 minutes to reset the system. Going to try that and I'll let you know if it works or not. Cheers!
T

 

I will check it tommorow. It may be it.

 

A failing battery is a strong candidate. The W210's are sensitive to battery voltage. To test the battery it must be disconnected from the car's electrical circuit and have a load applied by a battery load tester. A simple voltage check will not see the problem.

Losing sync on windows etc. and false error messages from the electronics are common examples of symptoms.

If the battery is bad, I suggest replacing it will the appropriate MB battery. About $170. They are cheaper batteries that will start of the car but if they only last half as long there's really no savings. Some people have reported getting 7-8 years with a MB battery. As always YMMV.

 

Talking about sensitive to battery? You are all lucky with just losing those electrical controls. Mine was locked at 2nd gear & reverse only. My 1st diagnosis was limp home mode - transmission. No CEL. It took a DAS system to find out that I have weak battery. Cost me $250.00 ($80.00 for DAS, $130.00 for Interstate battery, $40.00 labor). Erased all codes & All is fine & working. Battery is original MB - 11 years. Can't beat that!

 

+3 change your Battery.

 

Its not the battery guys. Its something else. How do you diagnose this problem?

 

Can a faulty window regulator cause this electrical mistery?

 

You diagnose it by taking the car to someone who can scan the CAN-BUS B system, and follow the diagnostic procedures to pinpoint the problem. This means a dealership or a very well tooled and educated indy shop.

I would suggest searching on benzworld.org and learning yourself on all of the components and some of the common failure modules and quick checks that can point to possible failure points. You'll find many problems stem from bad LCM (window switch module from spilled fluids) or PSE units (water under rear seat). Seat control modules are next, followed by rear window modules that get removed/replaced/bad connections on the 3rd window regulator replacement.

You get the idea. Keep us posted as I would love to see a successfully diagnosed problem. I'll tackle mine some more, when spring comes.

 

not the regulator, but the module that controls the regulator. can-bus uses little computers to say, "hey, i see you pressed down on that rear window switch." "let me go tell the computer you want to lower the window." so, there are modules for the windows, seats, sunroof, window switches, etc, along with all of the actual switches and motors.

each item diagnosed and replaced will be in the $500-$1000 range. maybe a little less if it's a window control module.

 

Thank you for your help. I need to leave my car for check up.