W210: Lights in Hatch Not Working
 

Hello,

I recently picked up a 1999 e320 wagon, and I have been working through all the misc issues. When I turn on the lights, I was getting a lamp failure warning on the dash.

I isolated the issue to the marker lights in the hatch, they don't light on the left or right. I do have Tag and reverse lights. I went through the process of checking all the fuses with a volt meter (next to the battery, under hood, and next to the light switch in the cabin). The fuse cards have conflicting info, but all the fuses are getting power. I checked every fuse in those three locations, and they all had power. I even pulled the interior cover for the hatch, and checked the bulbs. I checked for power to both plugs for the lights, and I wasn't getting any volts.

Just a little bit of background, the rear window regulators were bad when I bought th car, and the footwell on the passenger side was wet, including in the battery area. I did my best to dry it out, sucked out what I could with a shop vac, put a fan on it, and have some "Damprid" in the footwell. I also recently replaced the alternator which failed. The heated seats are also not operational on either driver or passenger seat. (I have not tested conductivity at the plug under seat yet).

Any information would be appreciated, as I need to get the car inspected to get my registration.

Are you talking about the interior lights in the rear? Those should light up when the hatch or either rear door is opened. On my 92, they are controlled by a rocker switch on the extreme left of the center console above the climate control system. Push the upper part of the switch to turn them on, center position is off, and lower position activates the door and hatch switches. Your 99 may not be the same, but worth checking.

I believe this function is taken care of by the door lock pump/module as its also a rudimentary signal aquisition module for the rear of the car. You said that the battery area was wet, the pump module sits right there.

but i dont think any interior lamp failure is displayed in the dash screen, its exclusively for the outside of the car. Check the little orange marker lights on the front bumper, they will also trigger that.

There are no parking lights located in the rear hatch. The rear parking lights are the lower and middle lights in the lamp assembly in the fender. The lights in the hatch are the backup lights and a rear fog light on the driver's side.
You may want to closely inspect the tail lamp housings where the bulb sockets insert for melted plastic causing an intermittent connection. I have also seen cheap bulbs cause issues.

turbo, as mentioned check the tail lamp housings for melted plastic. I recently replaced the left tail lamp assembly for that very reason. You need to buy the entire tail lamp assembly. It cost me $140 for a new assembly from our local MB dealer. I recommend buying a new assembly rather than a used one which may present the same problem shortly after purchase.