I have a red light on the dash of my '88 300E (49 state version) that comes on intermittantly. The light is located on the bottom right side of the cluster between the SRS light and the oxygen sensor light. My owner's manual does not mention this light but does make mention of a diagnostic light for California versions of which mine isn't I don't think. Anyone know what the light means. Seems to come on briefly once in awhile at freeway speeds. Frequency of occurrence is once a week or so. Thanks in advance for any and all replies.

Geoff Oliver