Hey all,

After having to put off finishing my 300SD for a long time due to school and family health problems, etc, today I finally got another transmission installed from a parts car I picked up over the summer, and the thing runs and drives like a champ . Unfortunately, there are some electrical problems now that I need to work through before the car will pass inspection, and I'm looking for help diagnosing some of them. Here they are:

1) The turn signals and 4-way flashers all light up but flash at an incredibly high frequency. I'm assuming this is either due to the 4-way switch or the flasher relay, both of which I have working spares for that I can swap in to test.

2) The right headlight (US sealed beam) is really dim, both low-beam and high-beam (it's dimmer on high beam). Could this be a bulb or would it be bad wiring? I'm thinking of starting by testing the bulb wiring and then moving to replacing the bulb if the wiring seems to check out (I have a spare bulb).

3) The brake lights do not light up when the brake pedal is pressed. I'm going to start by testing the switch at the brake pedal and go from there. Any thoughts on that?

4) The passenger's-side parking lights do not work, even though the turn signals do, which makes me think there is a wiring issue here.

5) None of the interior lights come on. Not the dome light, not the switch backlighting, not the instrument cluster. The instrument cluster does work, though, and so do the idiot lights on the bottom (brake, battery, glow plug lights, etc.). Haven't really even tried to start on diagnosing this yet. I checked all the fuses earlier and they looked ok but I will check again. What's weird is I know the dome light worked last night.

6) The wipers climbed 3-4 inches up the windshield and then stopped. You can hear some vague noise from the wiper motor when hitting the switch, so I'm going to put some current directly to the motor and see if it works or not (I'm guessing that the motor itself is dead but we'll see). I have a complete, working wiper system from a parts car so I can fix it whatever it is.

I'll update this thread as I work on diagnosing issues. If anyone wants to toss in thoughts on anything, please do! I'm looking for ideas here haha. I found some wiring diagrams so will study those as a help with testing.

Despite all this, the car runs and drives flawlessly except for mildly harsh shifts at partial "throttle". There's something funky going on with the vacuum system, so I'm going to start a separate thread for that. Despite not having been started for about 3-4 years and not driven in about 8, the car fired right up into a smooth idle in an instant and runs, drives, and stops incredibly well. It's really quite a pleasure to drive (picture after washing).

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"Senior Luna, your sense of humor is still loco... but we love it, anyway." -rickymay ____ "Your sense of humor is still loco... " -MBeige ____ "Señor Luna, your sense of humor is quite järjetön" -Delibes

1982 300SD -- 211k, Texas car, tranny issues ____ 1979 240D 4-speed 234k -- turbo and tuned IP, third world taxi hot rod

2 Samuel 12:13: "David said to Nathan, “I have sinned against the Lord.” And Nathan said to David, “The Lord also has put away your sin; you shall not die."