Hi Everyone,

Here's a fix to a problem I experienced with my car this morning.

The situation: The car started fine, just like it does every morning. I usually let it run for a few moments at full oil pressure before backing out of the garage. But today, just before backing out, the oil gauge indicated falling pressure. As soon as I saw the pressure drop, I turned off the engine. Once the engine was off, I realized that the fuel indicator was also falling at the roughly the same rate as the oil indicator before switching off the engine. Something must have cut off power to those gauges.

After a quick verification of oil level I tried to restart the car and the starter would not engage. Other symptoms included a buzzing sound near my W124's fuse box under the hood (driver's side), and three lit dash indicators: Battery, ABS, and ASR. The battery was relatively new and starting in the neutral shift lever position yielded the same results.

The solution: The stock anti-theft system has a starter cut off relay which is protected by Fuse #5 in the fuse box. In my case Fuse #5 was bad. Replacing it brought everything back to life again. My kind of repair!

Also, in some cases, according to my indy, (assuming the fuse is good) the relay can stick. (I'm not sure exactly where that relay is on my car. I think it is in the closed section just behind the aforementioned fuse box. Removal of six phillips head screws gains access...) Anyway, a temporary 'get home' fix for the sticky relay would be to have someone tap it while another person is attempting to start the car. Sometimes that is enough to unstick it for another start or two. Once home, you'd want to swap the relay with a new one. It should be inexpensive.

A final note with respect to proving out the fuse- don't rely on a visual check. Use a continuity light or meter. Don't ask me how I know this. Suffice it to say that the cost of a fuse pales in comparison to towing charges.

Hope this proves helpful.

Wittenberger

1995 E300D Blk/Blk 183Kmi

Thanks for posting this and good job figuring it out.

Is this anti-theft relay the same generic relay that is found throughout the relay box? I have a bunch of extras that I keep in my garage just in case. It's the same relay that's used for the seats.

__________________
-justin

1987 300TD, 1987 300TD
2008 R32, 2000 Passat Wagon

Justin-

Could be- Unfortunately I don't have either the documentation or experience to say for sure. Perhaps one of our sages could chime in on this.

Keeping extra relays is a great idea. Speaking of "just in case," it would be a good idea to keep a couple in the car...along with a few spare fuses. I sure could have used the fuses yesterday!

Wittenberger
1995 E300D Blk/Blk 183Kmi