As I 'm driving at times multiple items lose electrical power. For example, the radio turns off, windows & sunroof stop working, heated seats turn off and power seats do not work, sometimes power antenna lowers and raises and finally SRS light comes on for a few seconds. At other times everything works fine and then all items no longer work again. There is no consistent pattern except that perhaps movement and not time changes the situation. It is quite a nuisance when you park and can no longer roll up the windows or while driving the radio shuts off. The car is a 1995 E420 with 57,000 miles. I have changed the combination relay as I had erratic wiper movement and that is now resolved. Could the convenience relay be the culprit for some of the issues?

Also as of late the low beams do not go on, but high beams and fog lamps are fine. But these permanently stay off, not intermittent like the other problems.

Thanks ahead for any advice.

1995 E420 Fast!
1998 C280 Everything works!

Check all your battery connections and clean them with a wire brush and clean the terminals and between all connecting wires to the battery.

Also theck and clean the negative ground chassis connection.

Check your alternator output.

When the alternator fails the car will cut consumers one by one to save power to keep the engine running, one good indicator is the SRS light.

Does the car start sluggishly in the morning or right after an incident like described?

Turn your fuses as well. Those little metal contacts at the ends can built up crusties, and cause full or intermittant power transfer loss.

__________________
It is a truism that almost any sect, cult, or religion will legislate its creed into law if it acquires the political power to do so. Robert A. Heinlein


09 Jetta TDI
1985 300D

The car always starts well with full battery power even if sitting for a couple of weeks, but I will have to check things you mentioned even though in general nothing looks corroded at terminals and connections. Will check fuses too. Thanks

Check all your earth points also. - where the brown wires are grounded to the body and engine.
There is a point on the manifold close to the dipstick and IAC where the earth bonding is held down by a bolt. This often corrodes. Check the earth bonding at the bottom of the motor near the transmission.

Im having a simular problem.

When sitting in the car, I have the radio on. I turn the key off and remove it from the ignition.

all the power is off inside the cab (radio,lights,etc.)

I open the driver door and the srs light eluminates and the radio recives power and turns back on.

can someone shine some light on this for me? It really dosent cause a problem I just want to fix all the small things before they become worse.

Thanks

if i remember correctly that is the "warning module" which has a diode in it so that the power from the floor lights won't backfeed into the circuits when you open the doors.

__________________
David S Poole
European Performance
Dallas, TX
4696880422

"Fortune favors the prepared mind"
1987 Mercedes Benz 420SEL
1988 Mercedes Benz 300TE (With new evaporator)
2000 Mercedes Benz C280
http://www.w108.org/gallery/albums/A...1159.thumb.jpg

I second and third spinning the fuses and replacing them with copper ended barrel fuses.

Clean grounds of course.

Pull and reinstall all relays and connections you can find due to bimetallic corrsion like on the fuses. Especially if they salt roads in your area.