First off, thanks to all who replied for the help last week re: weird noises under the hood and my squeaky shifter. Problems solved.

OK, now for the new one....the ASR light has started coming on whenever I start the car with the engine warm. It has never come on with a cold start, or turned on while driving after a cold start. (I.e., I can drive the 30 miles from home to work or vice versa, and the light stays out.) If I stop to run an errand or get gas, it stays on after re-starting the car. There's no noticable effect in the performance of the car. (I haven't tried to spin the wheels or anything, though, since I don't want to compound the problem).

Now, when I changed the oil I noticed that there were some wires with deteriorating insulation running along the right side firewall and then down past the oil filter. I taped up the worst areas with electrical tape. It's not part of the main engine harness; that's already been replaced. So I'm thinking that messing with those wires caused a short somewhere, which is causing my problems, but I'm interested to hear alternate theories from people who know a lot more about these things than I. Any suggestions? BTW, the car has only 75,000 miles....
--Ethan

Possible brake light switch.

May want to get codes from pin #14 of diagnostic connector box.

There are three wires that are part of that harness. One is for the solenoid, the other two are oil level and oil temp wires. They deteriorate just like the main harness.

When mine did, the dealer said they could not obtain a new harness, so I fabricated a new one with automotive wire. The old wires shorted out my oil pressure sensor.

My indie tells me that the harness IS available though.

__________________
2009 ML350 (106K) - Family vehicle
2001 CLK430 Cabriolet (80K) - Wife's car
2005 BMW 645CI (138K) - My daily driver
2016 Mustang (32K) - Daughter's car

You're refering to the Battery [aka"B"] Harness for Starter and Oil Pressure Sender Sensor

Photos 2 & 3 at end of thread are of cable at oil filter and connector [to its right when facing engine]. '95 E320 wire harness question

Most likely the battery cable is ok. A few dollars for wire and a little soldering and you can DIY as I did. But you have to do some connections from under car. Connector [photo 3] uses pin connections to wire. De-solder and reuse them.

Oil level = Brown/Black [left side, front, bottom of block]
Oil Pressure = Brown/Green [left side, below oil filter]
Solenoid = Purple/White [on starter]

Bob
PS Good to disconnect battery ground before DIY.